ALBERT

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 493〈/p〉 〈p〉Author(s): Shivshankar Chaudhari, MinKyoung Baek, YongSung Kwon, MinYoung Shon, SeungEun Nam, YouIn Park〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Surface modification of a halloysite nanotube (HNT) was performed by piranha etching of the HNT surface to generate hydrophilic moiety on the surface. The HNT and surface-modified HNT (MHNT) were embedded in polyvinyl alcohol/polyvinyl amine (PVA/PVAm) membranes. Surface modification of the HNT was confirmed using X-ray photoelectron spectroscopy, Fourier transform infrared, and transmission electron microscopy analyses. The 5 wt% MHNT-embedded membrane showed the best pervaporation performance (flux = 0.13–0.031 kg/m〈sup〉2〈/sup〉 h and separation factor = 427–93,313) among all membranes at 40 °C with 80–90 wt% of isopropanol (IPA) in the feed solution. Up to 5 wt% loading of HNT and MHNT in the membrane, the flux decreased, while the separation factor increased and subsequently decreased continuously with further HNT and MHNT loading. This was attributed to the hydrophilicity arising from HNT inclusion in the membranes. The membrane performance was evaluated under various pervaporation-operating conditions. Based on the solution diffusion model, with increase in water content, flux increased, while separation factor decreased. The temperature dependence of flux followed the Arrhenius equation. The energy of activation for the permeation of water (25.99 kJ/mol) was less than that of IPA (143.49 kJ/mol for the 5 wt% MHNT-loaded membrane at an 85 wt% of feed IPA composition). Overall, the pervaporation data suggested that the presence of MHNT in the PVA/PVAm membrane benefited pervaporation dehydration.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219320379-ga1.jpg" width="301" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 492〈/p〉 〈p〉Author(s): Naofumi Ohtsu, Yuma Hirano, Kaho Yamaguchi, Kako Yamasaki〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A titanium oxide layer containing a small amount of Ni can be formed on a NiTi surface through anodization when using HNO〈sub〉3〈/sub〉 as an electrolyte. In this study, the effect of different HNO〈sub〉3〈/sub〉 concentrations on the surface characteristics of the alloy, including hydrophilicity, Ni-ion release, and antibacterial efficacy, was investigated. An oxide layer was fabricated, in which tiny pores were generated by pitting corrosion. The layer thickness and pore size varied with the concentration of the HNO〈sub〉3〈/sub〉 electrolyte. The hydrophilicity of the NiTi surface was dramatically improved through anodization owing to the formation of the oxide layer. The layer formed was expected to serve as a corrosion protection barrier; however, the Ni release rate from the anodized surface was higher than that of an untreated surface due to the generation of pores. The Ni release rate from the anodized surfaces varied depending on the electrolyte concentrations used, owing to the balance between the layer thickness and pore size. Ni ion release was advantageous from the view of antibacterial efficacies; the efficacies of NiTi alloy against 〈em〉E. coli〈/em〉 and 〈em〉S. aureus〈/em〉 were actually enhanced by anodization. Ni ion release was not beneficial with regards to allergenic reaction and cytotoxicity; the Ni ion release rate decreased rapidly when the alloy was soaked in a simulated body fluid. Thus, we concluded that anodization in HNO〈sub〉3〈/sub〉 is one possible approach to fabricate ideal NiTi medical devices with excellent antibacterial performance and biosafety.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 493〈/p〉 〈p〉Author(s): Pingan Zhang, Aimin Pang, Gen Tang, Jianru Deng〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this article, Molecular dynamics (MD) simulation were applied to investigate the adsorption behavior and mechanism of neutral polymeric bonding agents (NPBA) in nitrate ester plasticized polyether (NEPE). The simulation results indicate that due to the strong van der Waals (vdW) force interaction, NPBA has the highest binding energy with RDX compared to PEG and nitrate plasticizer. Then, the influences of temperature on the compatibility of nitrate plasticizer and two polymers, NPBA and PEG, were studied. The results show that PEG can dissolve in nitrate plasticizer over a wide range of temperature, while the compatibility of NPBA and nitrate plasticizer decrease with the reducing of temperature. Moreover, the adsorption behavior of the NPBA on RDX surface in nitrate plasticizer was investigated. The results demonstrate that the NPBA chains can penetrate through nitrate plasticizer, adsorb on the RDX surface, and form a compact protection layer, which prevents the bonding interface from nitrate plasticizer damage. Our researches afford a microscopic insight into the mechanism of NPBA, and can be helpful to the NPBA molecular and NEPE formulation design.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219320513-ga1.jpg" width="303" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 492〈/p〉 〈p〉Author(s): A. Dulmaa, H. Vrielinck, S. Khelifi, Diederik Depla〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Copper oxide thin films are grown by reactive magnetron sputter deposition. To define the parameter space to obtain CuO films, the influence of the oxygen partial pressure, the total pressure, and the discharge current was investigated on the phase formation. A clear change from pure copper, over cuprite (Cu〈sub〉2〈/sub〉O), and paramelaconite (Cu〈sub〉4〈/sub〉O〈sub〉3〈/sub〉) to tenorite (CuO) thin films with increasing oxygen partial pressure was observed using X-ray diffraction and Fourier transform infrared spectroscopy. The main driving force defining the phase composition is the oxygen partial pressure, while the influence of the total pressure, and the discharge current is minimal. A clear condition to obtain phase pure CuO films could be defined based on the measured discharge voltage. Both the domain size, and the Bragg peak position for pure CuO thin films can be correlated to the negative ion bombardment during film growth.〈/p〉〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 493〈/p〉 〈p〉Author(s): Yun Kon Kim, Sungjun Kim, Yonghwan Kim, Kyeonghui Bae, David Harbottle, Jae W. Lee〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Selective removal of 〈sup〉137〈/sup〉Cs and 〈sup〉90〈/sup〉Sr from aqueous environments is essential for the volume reduction and ultimate safe storage of nuclear waste. This study introduces a facile one-pot hydrothermal synthesis of Dual-cation form of TitanoSilicate (DTS, M〈sub〉3〈/sub〉HTi〈sub〉4〈/sub〉O〈sub〉4〈/sub〉(SiO〈sub〉4〈/sub〉)〈sub〉3〈/sub〉, M = Na〈sup〉+〈/sup〉 and K〈sup〉+〈/sup〉) for the effective and simultaneous removal of Cs〈sup〉+〈/sup〉 and Sr〈sup〉2+〈/sup〉. DTS showed enhanced adsorption capacities (469 mg/g for Cs〈sup〉+〈/sup〉 and 179 mg/g for Sr〈sup〉2+〈/sup〉) and the adsorption kinetics were extremely fast with around 98% and 〉99% removal achieved within 1 min from a dilute Cs〈sup〉+〈/sup〉 and Sr〈sup〉2+〈/sup〉 solution, respectively. Moreover, DTS indicated the superior selectivity for both Cs〈sup〉+〈/sup〉 and Sr〈sup〉2+〈/sup〉 due to the dual-cation incorporation in the structure. In groundwater, the distribution coefficients (K〈sub〉d〈/sub〉 at V/m = 1000 mL/g) for DTS were high for both Cs〈sup〉+〈/sup〉 (1 ppm, 2.9 × 10〈sup〉5〈/sup〉 mL/g) and Sr〈sup〉2+〈/sup〉 (1 ppm, 1.0 × 10〈sup〉5〈/sup〉 mL/g), and even in seawater DTS maintained a Cs〈sup〉+〈/sup〉 (1 ppm) K〈sub〉d〈/sub〉 value as high as 4.9 × 10〈sup〉4〈/sup〉 mL/g. Remarkably, DTS is synthesized as a membrane with graphene oxide for continuous removal of the radionuclides, which is extremely beneficial to purifying a large volume of contaminated water.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219320446-ga1.jpg" width="455" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 493〈/p〉 〈p〉Author(s): Sreejith Karthikeyan, Sehyun Hwang, Mandip Sibakoti, Timothy Bontrager, Richard W. Liptak, Stephen A. Campbell〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Thin-film photovoltaic research based on ternary or quaternary absorber materials has mainly concentrated on copper (indium/gallium) diselenide, CuIn〈sub〉x〈/sub〉Ga〈sub〉1-x〈/sub〉Se〈sub〉2〈/sub〉 (CIGS). This material has demonstrated exceptional energy conversion efficiencies. By altering the In/Ga ratio the band gap can be varied from 1.02 eV (for CuInSe〈sub〉2〈/sub〉) to 1.68 eV (for CuGaSe〈sub〉2〈/sub〉). However, research from leading groups showed that cells have maximum efficiency at or below 1.35 eV. This paper reports the challenges of using aluminium alloyed CIGS deposited with a single step co-evaporation method. Adding aluminium is found to reduce the bulk trap state density for wide gap devices. However, it created significant safety issues when compared to conventional CIGS co-evaporation deposition systems. The release of H〈sub〉2〈/sub〉Se when moisture comes in contact with aluminium selenide was resolved by placing exhaust lines at various places of the deposition chamber. A single phase CIAGS device with a bandgap of 1.30 eV was prepared using a co-evaporation method. The fabricated solar cell devices with CIAGS absorber layers and resulted in a photoconversion efficiency of 10.3%. A progressive rapid thermal annealing at various temperature resulted in a 10% increase in the overall efficiency at 300 °C. The efficiencies were reduced when the RTA temperature increased above 300 °C.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉SEM image of device cross section based on CIAGS absorber layer.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219320148-ga1.jpg" width="410" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 492〈/p〉 〈p〉Author(s): Beleta Bolvardi, Javad Seyfi, Iman Hejazi, Maryam Otadi, Hossein Ali Khonakdar, Seyed Mohammad Davachi〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Oil spill accidents and industrial oily wastewater are threatening all living species in the ecological system. Development of materials with special wettability for oil/water separation has been the subject of many researches. Herein, superhydrophobic and superoelophilic nanocomposite coatings, based on titanium dioxide (TiO〈sub〉2〈/sub〉) nanoparticles and polydimethylsiloxane (PDMS), were applied on metal meshes with different pore sizes (25 and 100 μm). Morphological analysis revealed that adding PDMS, as a binder, significantly changes the surface structure of the coatings. For 100 μm-sized meshes, PDMS causes a two-tier roughness whereas a uniform and finely packed single-scale nanostructure was formed for 25 μm-sized meshes upon PDMS addition. Exceedingly high content of nanoparticles was found to impose a detrimental influence on uniformity of morphology. All the samples exhibited superhydrophobicity; however, their mechanical durability results were significantly diverse. PDMS introduction was found to impose a substantial improvement in abrasion resistance. Oil/water separation experiments revealed that the mesh with smaller pore size exhibited a more efficient separation while a much shorter separation time and higher flux could be achieved by the mesh with larger pore size. In addition, the mesh with smaller pore size exhibited a more abrasion resistant coating which could be more beneficial in real-life applications.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 493〈/p〉 〈p〉Author(s): De-Cai Guo, Chun-Shui Sun, Wei Wu, Zhong-Shuai Wu, Jing Gao, Nan Su, Jian Chen〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The fabrication of nanocarbons possessing ultrathin graphitic structure and ultrahigh nitrogen doping simultaneously remains challenging so far. Herein, we develop a novel and versatile strategy to prepare ultrahigh nitrogen-doped hierarchical porous carbon with ultrathin graphitic framework (NHPCs), through the Schiff-base reaction of melamine and terephthalaldehyde in the presence of lithium oxide, as high-performance anodes for rechargeable lithium ion batteries. During one-pot solid-phase interface reaction, Li〈sub〉2〈/sub〉O was used to absorb the in-situ generating H〈sub〉2〈/sub〉O enhancing the formation of Schiff-based networks and LiOH was in-situ obtained, which can be used as active agent to increase the BET surface areas of final carbons. The obtained NHPCs present 3D hierarchical honeycomb-like morphology, ultrahigh nitrogen content up to 12.2 wt%, large specific surface area of 1260 m〈sup〉2〈/sup〉 g〈sup〉−1〈/sup〉. These unique structural properties allowed for fast ion diffusion and rapid electron transport, and offered enriched active sites for lithium storage. NHPCs presented a high reversible capacity of 880 mAh g〈sup〉−1〈/sup〉 at 100 mA g〈sup〉−1〈/sup〉 even after 100 cycles, and exceptional rate capability with 301 mAh g〈sup〉−1〈/sup〉 at 3000 mA g〈sup〉−1〈/sup〉, outperforming most reported nano‑carbons. Therefore, this strategy will open a new way to prepare heteroatom-doped porous carbons with a controllable hierarchical structure, for high-performance energy storage.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉Nitrogen-doped hierarchical porous carbon with ultrathin graphitic framework was prepared by the novel method of one-pot solid phase in situ templated synthesis strategy shows superior high electrochemistry performance for lithium-ions storage.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219319166-ga1.jpg" width="433" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 492〈/p〉 〈p〉Author(s): Liwei Wang, Huiyun Tian, Han Gao, Fazheng Xie, Kang Zhao, Zhongyu Cui〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Passivation behavior and surface chemistry of 304 stainless steel in alkaline solution with different HCO〈sub〉3〈/sub〉〈sup〉−〈/sup〉/CO〈sub〉3〈/sub〉〈sup〉2–〈/sup〉 concentrations are studied with a combined electrochemical and XPS analytical investigation. Cathodic and anodic reactions are inhibited and accelerated, respectively, attributed to the depletion of acceptable oxygen and variation of passive film properties. Increasing HCO〈sub〉3〈/sub〉〈sup〉−〈/sup〉/CO〈sub〉3〈/sub〉〈sup〉2–〈/sup〉 concentration does not alter the bilayer structure but leads to an intensification in electric field strength and composition changes including enrichment of oxidized Cr, increase of Fe(II)/Fe(III) ratio, and decrease of OH〈sup〉−〈/sup〉/O〈sup〉2–〈/sup〉 ratio of the film. Meanwhile, the film thickness is reduced and the point defect density is increased due to the enhanced film dissolution. High HCO〈sub〉3〈/sub〉〈sup〉−〈/sup〉/CO〈sub〉3〈/sub〉〈sup〉2–〈/sup〉 concentration increases the critical chloride concentration of 304 SS in alkaline solution, attributed to the inhibition of the localized acidification within the pits and suppression of the stable pit development.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 492〈/p〉 〈p〉Author(s): Rong Zhang, Liancheng Wang, Xi Yang, Zheng Tao, Xiaobo Ren, Baoliang Lv〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The surface chemistry of catalyst plays a vital role in the catalytic process. And the effects of surface groups of porous boron nitride (〈em〉p〈/em〉-BN) on the hydrogenation reaction have not been studied in detailed. In this work, two main surface species of Co/〈em〉p〈/em〉-BN catalyst were tuned thermally and their roles on the hydrogenation reaction were discriminated by α, β-unsaturated aldehyde hydrogenation reaction. The surface B〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉O content decreased at higher reduction temperature and the cobalt phase changed from CoO to the mixture of CoO and Co0. The Co/〈em〉p〈/em〉-BN-500 exhibited the highest selectivity to C〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/dbnd"〉O hydrogenation. And its turnover frequency (TOF) of 13.2 h〈sup〉−1〈/sup〉 is close to the optimal value of reported cobalt catalysts. When the reaction proceeds, hydrogenation rate of C〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/dbnd"〉O increases but that of C〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/dbnd"〉C decreases gradually, thus a surface groups variation was expected at the initial period. Further in-situ FTIR spectra showed the band intensity of edge N〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉H increases as the adsorption proceeds at 50°С but it decreases as the temperature rise to 200°С, in combined with the shift of C〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/dbnd"〉O adsorption peak, a intermolecular hydrogen bond between edge N〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉H and the terminal C〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/dbnd"〉O group was suggested, which account for the better selectivity to C〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/dbnd"〉O than C〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/dbnd"〉C.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219320045-ga1.jpg" width="490" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 493〈/p〉 〈p〉Author(s): Jin-hua Ren, Yu-ting Huang, Kai-wen Li, Jie Shen, Wan-yu Zeng, Chu-ming Sheng, Jing-jing Shao, Yan-bing Han, Qun Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Tm〈sup〉3+〈/sup〉 doped SnO〈sub〉2〈/sub〉 semiconductor thin films were prepared by RF magnetron sputtering method. The doping effects of rare-earth thulium on the crystal structures, optical properties, chemical compositions, surface morphologies of tin-oxide thin films, together with the electrical properties of the corresponding SnTmO thin film transistors (TFTs), were investigated. SnTmO semiconductor thin films with polycrystalline structures feature a wide bandgap of over 3.8 eV. XPS results reveal the typical photoelectron signals of Sn〈sup〉4+〈/sup〉 and Tm〈sup〉3+〈/sup〉. Smaller crystallite size and more grain boundaries can be formed in doped SnO〈sub〉2〈/sub〉 samples which may be responsible for the degradation of device mobility. It was found that the electrical properties of SnO〈sub〉2〈/sub〉 TFTs can be modulated by Tm〈sup〉3+〈/sup〉 incorporation. The appropriate Tm〈sup〉3+〈/sup〉 doping concentration is around 1.6 at.% within our experimental conditions. The optimized field-effect mobility, subthreshold swing, threshold voltage, on-off current ratio and the interface trap density are 5.5 cm〈sup〉2〈/sup〉 V〈sup〉−1〈/sup〉 s〈sup〉−1〈/sup〉, 0.618 Vdec〈sup〉−1〈/sup〉, −2.3 V, 5 × 10〈sup〉7〈/sup〉 and 6.7 × 10〈sup〉11〈/sup〉 cm〈sup〉−2〈/sup〉, respectively. Stability measurements show threshold voltage shifts of 12.3 V and −11.7 V in PBS and NBS process respectively. This study may provide useful understandings on rare-earth doped SnO〈sub〉2〈/sub〉 semiconductors.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219320367-ga1.jpg" width="399" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 492〈/p〉 〈p〉Author(s): Meng Chen, Yifu Zhang, Yanyan Liu, Jiqi Zheng, Changgong Meng〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Fabrication of a novel electrode material with efficient storage mechanism is a desirable strategy to build a better supercapacitors. Herein, a novel intercalation pseudocapacitance material, VO(OH)〈sub〉2〈/sub〉/CNT binary composite with cross-linked structure, is first successfully synthesized by a facile one-step hydrothermal method. This composite combines the intrinsic positive traits of each component, in which the synergistic efforts greatly enhance to achieve a considerable electrochemical performance. In the three-electrode system, VO(OH)〈sub〉2〈/sub〉/CNT composite electrode exhibits a capacitance of 256 F·g〈sup〉−1〈/sup〉 (512C·g〈sup〉−1〈/sup〉) at 0.5 A·g〈sup〉−1〈/sup〉 within the wide potential range of −0.8–1.2 V. More remarkably, the VO(OH)〈sub〉2〈/sub〉/CNT-based flexible symmetric supercapacitor delivers a high energy density of 32.08 Wh·kg〈sup〉−1〈/sup〉 at a power density of 63.65 W·kg〈sup〉−1〈/sup〉 in a large operating voltage of 2.2 V. As well as, it performs a well cycling stability that the capacitance retention is about 90% after 3000 cycles. For the factual application measurement, two devices in series can light red LED for 5 min after charging 100 s. This work enriches the exploration of vanadium oxyhydroxides' pseudocapaicitance performance, which is of great significance to the future application of vanadium oxyhydroxides in energy storage.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉VO(OH)〈sub〉2〈/sub〉/CNT electrode material with cross-linked structure performs the excellent intercalation pseudocapacitance. VO(OH)〈sub〉2〈/sub〉/CNT flexible SSC device can deliver a high energy density of 32.08 Wh·kg〈sup〉−1〈/sup〉 at a power density of 63.65 W·kg〈sup〉−1〈/sup〉 in a large operating voltage of 2.2 V. And after charging for 100 s, two devices in series can light red LED for 5 min.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219320057-ga1.jpg" width="301" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 492〈/p〉 〈p〉Author(s): Lan Chen, Xinzhou Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Owing to the layer-by-layer deposition characteristic of fused deposition modeling (FDM) process, parts produced via FDM have typical low surface quality and do not satisfy the requirements for end-use applications. Therefore, it is necessary to improve the surface quality of parts produced via FDM. In this study, laser polishing technology was employed to enhance the surface quality of aluminum fiber/polylactide acid (Al/PLA) composite parts produced via FDM. The surface roughness, surface morphology, dynamic mechanical properties, and tensile properties were investigated. With optimal polishing parameters, the laser polishing process removed the defects formed during the FDM process. The surface roughness was reduced from the initial value of 5.64 μm to 0.32 μm (〈em〉Ra〈/em〉). The dynamic mechanical analysis (DMA) results showed that there was a remarkable improvement in the storage modulus (〈em〉E〈/em〉′), loss modulus (〈em〉E〈/em〉"), and glass transition temperature of Al/PLA composite specimens after laser polishing. The re-melted and polished surface of the specimens also led to improvement in the tensile strength and Young's modulus. Lastly, the fracture morphologies were observed, and the possible strengthening mechanism was also discussed. These results indicate that laser polishing can be an efficient method for the surface polishing of FDM-printed parts.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219319786-ga1.jpg" width="273" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 492〈/p〉 〈p〉Author(s): Sher Bahadar Khan, Kalsoom Akhtar, Esraa M. Bakhsh, Abdullah M. Asiri〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A facile, cheap and efficient system has been developed for selective detection and removal of 4-nitrophenol. Herein, cerium oxide-copper oxide (CeO〈sub〉2〈/sub〉-Cu〈sub〉2〈/sub〉O) and CeO〈sub〉2〈/sub〉-Cu〈sub〉2〈/sub〉O/chitosan (CeO〈sub〉2〈/sub〉-Cu〈sub〉2〈/sub〉O/CH) nanocomposites were coated on glassy carbon electrode to evaluate their electrochemical behavior toward 4-nitrophenol via cyclic voltammetry. The response of coated electrodes toward 4-nitrophenol were remarkable, in which the reduction peak current of 4-nitrophenol was increased as compared to bare electrode. This specifies that such nanocomposites significantly boost the electrochemical reduction of 4-nitrophenol and therefore, we demonstrated that the nanocomposites exhibit outstanding selectivity and sensitivity toward 4-nitrophenol detection. The effects of different parameters including pH and scan rate were tested. The reduction peak current of 4-nitrophenol is proportionate with its concentration in the range 74–375 μM, and the correlation coefficient was 0.998. The detection limit is 2.03 μM (S/N = 3). This simplistic system was effectively implemented to the detection of 4-nitrophenol in real water samples, with reasonable recovery values (92.5–99.85%). Furthermore, we demonstrated that the nanocomposite displays an excellent catalytic ability for the transformation reaction of 4-nitrophenol to 4-aminophenol by NaBH〈sub〉4〈/sub〉. Such a system could be applicable for diverse applications in catalysis, sensing and environmental sciences.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S016943321931921X-ga1.jpg" width="271" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 492〈/p〉 〈p〉Author(s): Wang Li, Xin Shen, Rong Zeng, Jian Chen, Weiming Xiao, Shunmin Ding, Chao Chen, Rongbin Zhang, Ning Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The interaction of the metal and support in copper-ceria oxide catalysts has been proven to have extremely favorable effects on catalytic performance in CO oxidation. Therefore, how to construct more copper-ceria interfaces becomes the key to improve the catalytic activity. Herein, we developed a facile approach to prepare copper-ceria nanosheets with high concentration of interfacial active sites (active copper species sites and oxygen vacancies) using GO as a sacrificial template. Notably, GO was used as an excellent platform to grow precursors of both the Cu and Ce on its surface. Then, transfer them to metal oxides nanosheets by calcination. The CuCe-GO-X catalysts were characterized by SEM, TEM, In situ DRIFT, AFM, XRD, XPS, H〈sub〉2〈/sub〉-TPR and Raman spectra and applied in CO oxidation. The results demonstrate that CuCe-GO-600 nanosheets catalyst with about 10 nm thickness shows a higher concentration of oxygen vacancies (7.79%) and active copper species sites (2756 μmol g〈sup〉−1〈/sup〉) in the interface of copper-ceria than those of other CuCe-GO-X catalysts. Moreover, CuCe-GO-600 displays a highest catalytic activity (complete conversion at 90 °C with a space velocity of 54,000 mL (h g〈sub〉cat〈/sub〉)〈sup〉−1〈/sup〉).〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219320276-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 492〈/p〉 〈p〉Author(s): Yuexin Liu, Yanzhong Wang, Huiqi Wang, Peihua Zhao, Hua Hou, Li Guo〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Due to the large specific surface area and potential redox sites, metal organic frameworks (MOFs) are considered as a promising electrode material for supercapacitors. However, the low electrical conductivity of MOFs impedes their application in supercapacitors. Here, the NiCo-MOF/acetylene black composites were facily fabricated by an ultrasonic method, in which acetylene black was uniformly distributed between NiCo-MOF nanosheets and formed a conductive network, thus improving the electrical conductivity of NiCo-MOF as well as hindering their aggregation. The as-obtained NiCo-MOF/acetylene black composites exhibit high specific capacitance of 916.1 F g〈sup〉−1〈/sup〉, remarkable rate capability and cycling stability compare to the pure NiCo-MOF. In addition, an asymmetrical supercapacitor were also constructed, which achieved a maximum energy density of 33.84 Wh kg〈sup〉−1〈/sup〉 at a power density of 750 W kg〈sup〉−1〈/sup〉 and good cycling stability with 85.25% of initial capacitance after 5000 cycles.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉The sheet-like NiCo-MOF/AB nanocomposite is synthesized via an ultrasonic method. The NiCo-MOF/AB composites exhibit a high specific capacitance of 916.1 F g〈sup〉−1〈/sup〉 at 1 A g〈sup〉−1〈/sup〉. The assembled asymmetric supercapacitors show high energy density of 33.84 Wh kg〈sup〉−1〈/sup〉 with a power density of 750 W kg〈sup〉−1〈/sup〉, and the capacitance retention remains 85.25% after 5000 cycles at 5 A g〈sup〉−1〈/sup〉, indicating the excellent cycling stability.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219319646-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 492〈/p〉 〈p〉Author(s): Yanting Yang, Liangguo Yan, Jing Li, Jingyi Li, Tao Yan, Meng Sun, Zhiguo Pei〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Three TiO〈sub〉2〈/sub〉 and Zn-Al-layered double hydroxide composites, denoted LDH-TiO〈sub〉2〈/sub〉 composites, were prepared using the sol–gel method and characterized utilizing scanning and transmission electron microscopy with energy dispersive spectroscopy, ultraviolet–visible diffuse reflectance spectroscopy, X-ray diffraction, N〈sub〉2〈/sub〉 adsorption–desorption, X-ray photoelectron spectroscopy, photocurrent, photoluminescence and electrochemical impedance spectroscopy techniques. The characterization results illustrated that TiO〈sub〉2〈/sub〉 was attached onto the surface of LDH and the sizes of both TiO〈sub〉2〈/sub〉 and LDH particles were in the nanoscale range. The combination of LDH and TiO〈sub〉2〈/sub〉 promoted the photogenerated electron–hole transfer and separation. The removal abilities of the LDH-TiO〈sub〉2〈/sub〉 composites for Cr(VI) were evaluated using the synergistic adsorption and photocatalytic method. The adsorption percentages of the three LDH-TiO〈sub〉2〈/sub〉 composites for 20.0 mg/L Cr(VI) solutions ranged between 26% and 75%, and upon ultraviolet irradiation, the total removal percentages rapidly increased to approximately 100%. The removal efficiency for Cr(VI) depended on the TiO〈sub〉2〈/sub〉 contents of the LDH-TiO〈sub〉2〈/sub〉 composites. Increasing the TiO〈sub〉2〈/sub〉 percentage resulted in decrease in the adsorption capacities and increase in the photocatalytic removal ratios. The kinetic and isothermal data well fitted the pseudo-second-order and Langmuir equations, respectively. The high removal efficiencies suggested that the composites were suitable for the treatment of Cr(VI)-containing wastewater.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219319555-ga1.jpg" width="361" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 491〈/p〉 〈p〉Author(s): Zhenjiang Li, Xiaomei Wang, Xuehua Wang, Yusheng Lin, Alan Meng, Lina Yang, Qingdang Li〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Non-noble metal catalysts for photo/electrocatalytic water splitting are quite feasible for solving the problems of growing energy demand and environmental pollution. In this paper, noble-metal free Mn-Cd-S@amorphous-Ni〈sub〉3〈/sub〉S〈sub〉2〈/sub〉 hybrid catalyst (MCS@a-Ni〈sub〉3〈/sub〉S〈sub〉2〈/sub〉) with bifunctionality of photocatalytic hydrogen evolution and electrocatalytic OER is designed and prepared by simple hydrothermal method. The characterization results show that Mn-Cd-S was composed of cubic manganese sulfide and manganese doped cadmium sulfide, and amorphous Ni〈sub〉3〈/sub〉S〈sub〉2〈/sub〉 coating on the surface of Mn-Cd-S. The resultant Mn-Cd-S@amorphpus-Ni〈sub〉3〈/sub〉S〈sub〉2〈/sub〉 catalyst presents good stability and a high photocatalytic H〈sub〉2〈/sub〉 evolution rate of 12,069.27 μmolh〈sup〉−1〈/sup〉 g〈sup〉−1〈/sup〉. Besides, both Mn-Cd-S and Mn-Cd-S@amorphpus-Ni〈sub〉3〈/sub〉S〈sub〉2〈/sub〉 show good OER property with overpotential of 333 mV. Mn-Cd-S@amorphpus-Ni〈sub〉3〈/sub〉S〈sub〉2〈/sub〉 shows more favorable kinetics than that of Mn-Cd-S for OER. Moreover，the mechanism of the enhanced photo/electrocatalytic performance is investigated in detail. This work provides references for developing the catalysts with both photocatalytic and electrocatalytic properties.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉The Mn-Cd-S@amorphous-Ni〈sub〉3〈/sub〉S〈sub〉2〈/sub〉 hybrid catalyst (MCS@a-Ni〈sub〉3〈/sub〉S〈sub〉2〈/sub〉) was composed of cubic MnS, Mn doped CdS, and amorphous Ni〈sub〉3〈/sub〉S〈sub〉2〈/sub〉 coated on the surface of MCS. MCS@a-Ni〈sub〉3〈/sub〉S〈sub〉2〈/sub〉 possesses excellent photocatalytic H〈sub〉2〈/sub〉 evolution rate of 12,069.27 μmolh〈sup〉−1〈/sup〉 g〈sup〉−1〈/sup〉 and good electrocatalytic OER overpotential of 333 mV.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219316216-ga1.jpg" width="449" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 492〈/p〉 〈p〉Author(s): Shujuan Zhang, Li Liu, Jieyu Yang, Yiqing Zhang, Zhengrui Wan, Liqun Zhou〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Well-dispersed trimetallic Pd-Ru-Bi alloy nanoparticles (NPs) were successfully embedded in the three-dimensional (3D) rGO/MOF-199 by a facile hydrothermal and in situ impregnation-reduction method. Among the mono-, bi- and tri-metal@rGO/MOF-199 electrocatalysts, the trimetallic PdRuBi@rGO/MOF-199 exhibited the highest catalytic activity and durability towards ethylene glycol oxidation reaction (EGOR) under the alkaline condition, as high as 213.93 mA cm〈sup〉−2〈/sup〉, is about 7.23 times higher than that of commercial Pd/C. The outstanding electrocatalysis oxidation performance of the PdRuBi@rGO/MOF-199 is attributed to the unique 3D structures with trimetallic composition and strong synergistic effects of Pd, Ru and Bi nanoalloys that providing plenty of interfaces and achievable reaction active sites. Furthermore, the introduction of GO in MOF-199 matrix conduces to the superior electron transfer and large surface area, which are beneficial to improve the catalytic ability of the catalyst. The study on the new composites offers a conception and applicable way to develop the advanced Pd-based electrocatalysts for high performance direct ethylene glycol fuel cells.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 492〈/p〉 〈p〉Author(s): Chao Peng, Fanlin Zeng, Bin Yuan, Youshan Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Several nanoindentation MD simulations were conducted to investigate the indentation size effect (ISE) of Polystyrene (PS) and Polyethylene (PE) at nano-scale using different indenters and loading rates. A strain gradient elasticity model in which the ISE is related to the Frank energy caused by finite bending stiffness and neighboring interactions of chains was imported to describe the ISE in this work. Two large-scale molecular substrates for PS and PE were constructed to compare the ISE performance during indentation simulations. The spherical indenter was firstly considered, and an uptrend of the calculated hardness and modulus with increasing indenter radius was found for both PS and PE. A conical indenter consisting of 25 virtual rigid spheres used in LAMMPS was designed. Considering different tip sizes and loading rates, indentation simulations using these conical indenters were conducted. The uptrend of hardness curves at the initial indentation stage was also found in conical cases. Through fitting the hardness curves, the strengthening effects of tip size and loading rate were certified, especially for PS. At nano-scale, the dominant effect of benzene ring component on ISE performance was confirmed. The downtrend of ISE was found to exist at nano-scale for PE although it was not obviously found in experimental cases and the contributing factors for this kind of ISE were discussed.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219318859-ga1.jpg" width="475" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 492〈/p〉 〈p〉Author(s): Zhaoxi Chen, Li Qiao, Julien Hillairet, Yuntao Song, Viviane Turq, Peng Wang, Raphael Laloo, Jean-Michel Bernard, Kun Lu, Yong Cheng, Qingxi Yang, Caroline Hernandez〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Compounding Au-Ni with carbon (C) lubricants is a feasible approach to improve its mechanical properties and wear performance. In this study, 3.5 μm-thick Au-Ni/C nanocomposite coatings with a low residual stress on CuCrZr substrates by magnetron sputtering were developed. Face-centered cubic and hexagonal close-packed stacking structures were both confirmed in the composite coatings based on transmission electron microscopy and X-ray diffraction analyses. Amorphous C (a-C) was confirmed to be the structure of C in the composite coatings, and its graphitization transition with an increase in the C content was validated by X-ray photoemission spectra and Raman spectroscopy. By compounding 0.88 wt% a-C, the hardness of the Au-Ni/a-C coating reached 400 HV, which is twice higher than that of the Au-Ni coating. The electrical resistivity of the Au-Ni/a-C coating is relatively stable with an increase in the a-C content. As graphitization occurred on the wear track, the produced composite coatings showed a minimum wear rate of 2.2 × 10〈sup〉−6〈/sup〉 mm〈sup〉3〈/sup〉/N·m under atmospheric conditions, which is half that of the Au-Ni reference coating. Under vacuum, the wear performance of the produced Au-Ni/a-C composite coatings was similar to that of the Au-Ni reference coating.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S016943321931966X-ga1.jpg" width="335" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 492〈/p〉 〈p〉Author(s): Zehra Irem Yildiz, Tamer Uyar〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The free-standing and fast-dissolving nanofibrous films from inclusion complexes (ICs) of paracetamol with two different cyclodextrins, hydroxypropyl-beta-cyclodextrin (HPβCD) and sulfobutylether-beta-cyclodextrin (SBE-β-CD) were produced through electrospinning without using polymer matrix. The morphology of the nanofibers (NFs) was uniform and bead-free as confirmed by scanning electron microscopy imaging. The chemical, structural and thermal characteristics of the electrospun paracetamol/CD-IC NFs were investigated by X-ray diffractometry, Fourier transform infrared spectroscopy, differential scanning calorimetry, thermal gravimetric analyzer and proton nuclear magnetic resonance. The aforementioned methods indicated the successful formation of ICs of paracetamol with both CD types (HPβCD and SBE-β-CD). Besides, paracetamol/CD-IC NFs exhibited different features and properties from pristine paracetamol. For instance, the crystalline state of pristine paracetamol was transformed into amorphous state by CD-IC NFs formation which is important for the water-solubility increment of the drug molecules. Moreover, thermal studies indicated that paracetamol became thermally more stable in CD-IC NFs. The molar ratio of paracetamol:CD was found as ~0.85:1.00 for paracetamol/HPβCD-IC NFs and ~0.80:1.00 for paracetamol/SBE-β-CD-IC NFs. The dissolution behavior of paracetamol/CD-IC nanofibrous films was examined by exposing them to water. The electrospun paracetamol/CD-IC nanofibrous films showed fast-dissolving character in water due to the CD-ICs formation and high surface area of nanofibrous structure.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219319464-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Ehsan Rahimi, Ali Kosari, Saman Hosseinpour, Ali Davoodi, Henny Zandbergen, Johannes M.C. Mol〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this study, we report on a combined microscopic, analytical and electrochemical characterization of the nanoscopic passive layer on a tungsten‑molybdenum-containing super duplex stainless steel. We used scanning transmission electron microscopy/energy dispersive X-ray spectroscopy, scanning Kelvin probe force microscopy, scanning tunneling spectroscopy, and Mott–Schottky electrochemical impedance spectroscopy analysis to correlate the local chemical composition and electronic properties of passive layers on austenite and ferrite phases. The passive layer on the ferrite phase contains a higher amount of Mo, W, and Cr, which accommodates a higher nobility of ferrite and a higher local energy of the band gap compared to those on the austenite. The two aforementioned phases exhibit a different composition and semi-conductive properties of their passive layers leading to dissimilar local corrosion susceptibility. These findings are of pivotal importance in further studies of austenite and ferrite phase resolved corrosion resistance of duplex stainless steel demanding a dedicated alloying strategy.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324316-ga1.jpg" width="296" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Shan-Shan Guan, Sha-Sha Ke, Fei-Fei Yu, Hong-Xiang Deng, Yong Guo, Hai-Feng Lü〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉By means of density functional theory-based spin polarized first-principles computations, we systematically investigate the stable geometry, total energy, magnetic and electronic properties of 3d transition metal (TM) atoms substituted and adsorbed on monolayer (ML) Janus MoSSe. We first identify the most stable binding sites and their corresponding total energies as well. The results show that the most stable adsorption site is above the Mo atoms in the S atom side. It is found that the TM atoms substitution and adsorption do not destroy the stability of ML Janus MoSSe. Our calculations predict the magnetism could be induced in ML Janus MoSSe by the substitution of Cr, Mn, Fe, Co, and Ni atoms, respectively. However, for the adsorbed case, only Cr, Mn, Fe, and Co atoms could induce magnetism in the MoSSe substrate. We found that the band structures of Janus MoSSe can be efficiently modified by doping it with TM atoms (adsorbed or susbtitutionally located in the Janus MoSSe monolayer). Our investigation indicates that TM atoms-doped ML Janus MoSSe has a potential application for spintronics and optoelectronics.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324894-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Shawei Tang, Yaoyu Zhang, Hongshan San, Jin Hu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Controlling the corrosion rate of magnesium alloys is the critical way to demonstrate their excellent performance in the practical application, it is imperative to design and construct a surface to allow better expeditions adaptation to the application environment. A hydrophobic coating with a good adhesion to the substrate is required. In this study, calcium myristate coating, cerium myristate coating and calcium/cerium myristate mixed coating were fabricated respectively on the surface of AZ31 magnesium alloy by a one-step electrodeposition. The coating characteristics were studied. The corrosion behavior of the coated samples was investigated and the corrosion mechanism was also discussed. The results showed that all three coatings exhibited hydrophobicity with little difference. The presence of Ce ions in the electrolyte promoted the formation of the corresponding coating, and the Ce coating with cracks had the maximum thickest and a poor adhesion to the substrate The Ca coating and Ca/Ce mixed coating presented a good adhesion to the substrate. Compared with the single myristate coatings, the mixed coating exhibited improved corrosion performance. The EIS evolution reveals that the protection effect of the coatings gradually decreases during the immersion process, which is caused by the formation of porous hydrated coating on the surface.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324249-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Sumit Bera, P. Behera, A.K. Mishra, M. Krishnan, M.M. Patidar, R. Venkatesh, V. Ganesan〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Microwave-assisted solvothermal route has been followed to synthesize Sb〈sub〉2〈/sub〉Te〈sub〉3〈/sub〉 nanomaterial. The morphology and topography of the material have been studied in FESEM and AFM measurements respectively. The optical band gap of the material is found to be ~ 0.25 eV as measured in IR spectroscopy. Temperature dependent resistivity of the nanostructure shows thermal activation behavior in the high temperature region as well as it follows 3D Variable Range Hopping mechanism in the moderate temperature region. Electron-electron interaction and quantum interference dominated upturn in the resistivity is observed at T 〈 24 K. Low field magnetoconductivity (MC) shows disorder induced weak localization (WL) which makes over to weak antilocalization (WAL) at T ≥ 4 K. MC after post annealing of the sample shows WAL behavior at T 〈 4 K also. Quantum correction to the low field magnetoconductivity of the material follows Hikami-Larkin-Nagaoka (HLN) equation. The obtained parameters of the HLN equation indicate that the system follows the 2D conduction mechanism and presence of a single conduction channel at low temperature. High field MR exhibits linear and positive magnetoresistance (LPMR) which suggests the survival of robust topological surface state conduction in the nanostructured bulk Sb〈sub〉2〈/sub〉Te〈sub〉3〈/sub〉 topological insulator.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324511-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Meixuan Li, Huiyuan Wang, Yun Zhu, Di Tian, Ce Wang, Xiaofeng Lu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉It is extremely necessary to develop high-performance noble-metal-free hydrogen evolution reaction (HER) electrocatalysts applied over the whole pH values to replace expensive Pt-based catalysts. Herein, a typical metal-semiconductor heterostructure with metallic Mo and Mo〈sub〉2〈/sub〉C nanoparticles encapsulated in nitrogen-doped carbon nanofibers (N-CNFs) is fabricated via the pyrolysis of electrospun polyacrylonitrile (PAN)/cellulose acetate (CA)/bis(acetylacetonato)dioxomolybdenum (MoO〈sub〉2〈/sub〉(acac)〈sub〉2〈/sub〉) nanofibers. The unique porous and channel-rich structure of Mo/Mo〈sub〉2〈/sub〉C/N-CNFs can be manipulated by varying the mass ratio of polyacrylonitrile and cellulose acetate, leading to the exposure of abundant active centers and the acceleration of rapid mass transport. In addition, the synergetic effect among metal and semiconductor as well as the excellent conductivity of the N-CNFs result in excellent HER activity and stability over a wide pH range. To achieve the current density of 10 mA cm〈sup〉−〈/sup〉〈sup〉2〈/sup〉, the optimized Mo/Mo〈sub〉2〈/sub〉C/N-CNFs exhibit overpotentials of 175, 162 and 294 mV in 0.5 M H〈sub〉2〈/sub〉SO〈sub〉4〈/sub〉, 1 M KOH and 0.1 M phosphate buffer solution (PBS), respectively. This work provides a feasible approach to synthesize high-performance and economical hydrogen evolution electrocatalysts at all pH values for renewable energy-related applications.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉Mo/Mo〈sub〉2〈/sub〉C encapsulated in nitrogen-doped carbon nanofibers as efficient heterojunction electrocatalysts for hydrogen evolution reaction have been developed.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324699-ga1.jpg" width="301" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Zili Zhang, Zhuji Jin, Jiang Guo, Xiaolong Han, Qing Mu, Xianglong Zhu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Yttrium aluminum garnet (Y〈sub〉3〈/sub〉Al〈sub〉5〈/sub〉O〈sub〉12〈/sub〉, YAG) crystal is widely used for laser applications. However, due to its high hard and brittle nature, high surface quality and high material removal rate (MRR) are difficult to be achieved. In this study, to solve the problem, a novel CMP slurry was developed, which contains 8 wt% ZrO〈sub〉2〈/sub〉 abrasives, 5 wt% Na〈sub〉2〈/sub〉SiO〈sub〉3〈/sub〉·5H〈sub〉2〈/sub〉O, 0.3 wt% MgO and deionized water. After polishing, the surface roughness and MRR achieved 0.08 nm Ra and 34 nm/min respectively. The reaction mechanism during polishing was elucidated based on the results of grazing incidence small angle X-ray diffraction (GIXRD) and X-ray photoelectron spectroscopy (XPS). The results show that AlOOH and YOOH generated from hydration reaction react with Si–OH in Na〈sub〉2〈/sub〉SiO〈sub〉3〈/sub〉 aqueous solution to form soft andalusite and yttrium silicate, then MgO combines with andalusite to produce montmorillonite. All soft products are removed mechanically by ZrO〈sub〉2〈/sub〉 abrasives, obtaining the ultra-smooth surface of YAG crystal.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219323980-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Eunseok Oh, Sangwoo Lim〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Dissolution of the high dose ion-implanted photoresist which has carbonized C〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉C cross-linked crust layer was demonstrated by using nitrate-infused superheated water. The ion-implanted photoresist was partially dissolved in pure superheated water at 200 °C, but the crust layer was not dissolved. The dissolution of the ion-implanted photoresist was greatly improved with the addition of nitrate compounds, such as HNO〈sub〉3〈/sub〉, Zn(NO〈sub〉3〈/sub〉)〈sub〉2〈/sub〉, Cu(NO〈sub〉3〈/sub〉)〈sub〉2〈/sub〉 and Fe(NO〈sub〉3〈/sub〉)〈sub〉3〈/sub〉, to the superheated water. In particular, the ion-implanted photoresist was completely dissolved when the nitrate-infused aqueous solution produced H〈sup〉+〈/sup〉 concentrations higher than 1 × 10〈sup〉−5〈/sup〉 M and NO〈sub〉3〈/sub〉〈sup〉−〈/sup〉 concentrations higher than 0.0156 M. When H〈sup〉+〈/sup〉 and NO〈sub〉3〈/sub〉〈sup〉−〈/sup〉 ions were sufficiently present in superheated water, NO〈sub〉2〈/sub〉, which is very reactive with carbon, was produced. Based on the 〈em〉in〈/em〉-〈em〉situ〈/em〉 spectroscopic analysis, it was suggested that the cleavage of the C〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉C bond between the aromatic rings and the backbone chains in the crust structure by NO〈sub〉2〈/sub〉 initiated the dissolution reaction. Additionally, 4-nitrophenol, aliphatic compounds and 〈em〉trans〈/em〉-4,4-azodiphenol were produced and then they were decomposed to the 4-aminophenol and other gases. Therefore, it was concluded that H〈sup〉+〈/sup〉, NO〈sub〉3〈/sub〉〈sup〉−〈/sup〉, and NO〈sub〉2〈/sub〉 in superheated water were the key species to dissolve the crust layer and the bulk ion-implanted photoresist.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324754-ga1.jpg" width="301" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Jae Seo Lee, Sang Jin Lee, Seok Bin Yang, Donghyun Lee, Haram Nah, Dong Nyoung Heo, Ho-Jin Moon, Yu-Shik Hwang, Rui L. Reis, Ji-Hoi Moon, Il Keun Kwon〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Titanium implants (Ti) have been widely used in several medical fields. In clinical practice, Ti can become contaminated with bacteria through a variety of mechanisms. This contamination can lead to implant failure and serious infections. In this study, we aimed to develop a new, hybrid Ti with good biocompatibility and antibacterial properties by immobilizing ceftazidime (CFT) onto the Ti surface through polydopamine (PDA) and polyethyleneimine (PEI) chemistry. Hybrid Ti was confirmed by assessing the cell proliferation of human adipose-derived stem cells using a cell counting. The biofilm formation across the Ti surface of two bacterial strains associated with nosocomial infections, 〈em〉Pseudomonas aeruginosa〈/em〉 and methicillin-resistant 〈em〉Staphylococcus aureus〈/em〉, was evaluated by scanning electron microscopy. The viability of the bacteria exposed to Ti surface was evaluated by cell counting. Our results clearly demonstrate that the bacterial biofilm formation as well as bacterial viability was significantly reduced on the hybrid Ti as compared to the control, Ti alone. Collectively, the Ti surface was successfully modified to form the hybrid Ti exhibiting good biocompatibility and antibacterial properties through PDA, PEI, and CFT grafting. Within the limitations of this 〈em〉in vitro〈/em〉 study, we conclude that the hybrid Ti may be useful for successful implant treatment.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324729-ga1.jpg" width="292" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Denis Music, Damian M. Holzapfel, Felix Kaiser, Erik Wehr〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Using molecular dynamics based on density functional theory, interaction of aspartic acid (C〈sub〉4〈/sub〉H〈sub〉7〈/sub〉NO〈sub〉4〈/sub〉) with room-temperature thermoelectrics Bi〈sub〉2〈/sub〉Te〈sub〉3〈/sub〉, SnSe, MgAgSb, and TiO〈sub〉2〈/sub〉 alloyed with V is investigated. Aspartic acid is a common amino acid in mammals, decorating a cell membrane, and hence relevant for biocompatibility. Ti(0001), Zn(0001), Pd(111), Pb(111), and Cu(111) surfaces are employed to gauge such interactions, yielding an approximate adsorption energy threshold of −0.060 eV atom〈sup〉−〈/sup〉〈sup〉1〈/sup〉. Based on this threshold, Bi〈sub〉2〈/sub〉Te〈sub〉3〈/sub〉(0001) and SnSe(001) are rendered inert, while MgAgSb(001) and TiO〈sub〉2〈/sub〉(001) alloyed with V are proposed to be biocompatible. An aspartic acid molecule undergoes a non-dissociative adsorption on MgAgSb(001). The interaction of aspartic acid with TiO〈sub〉2〈/sub〉(001) alloyed with V is characterized by deprotonation of a carboxyl group, a subsequent Ti〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉O interfacial bond formation, and a reaction of an amino functional group with Ti. Short covalent-ionic bonds across these interfaces support the findings. These results may inspire future research on self-powered biomedical devices.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219325139-ga1.jpg" width="354" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Sen-Yan Zhong, Xue-Qing Gong〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Cerium dioxide (CeO〈sub〉2〈/sub〉) has a wide range of applications in the field of heterogeneous catalysis. Different facets can be exposed at CeO〈sub〉2〈/sub〉 nanomaterials with different morphologies, and these facets can exhibit very different catalytic activities. Previous studies focusing on the activities of various CeO〈sub〉2〈/sub〉 facets largely relied on the calculated energetics such as surface energies and oxygen vacancy formation energies, and the activities of the low-index CeO〈sub〉2〈/sub〉 surfaces obtained in these ways follow the order (110) 〉 2 × 1 reconstructed (110) 〉 (111). In this work, in order to more thoroughly examine the surface physicochemical properties, we used a combination of molecular dynamics (MD) and density functional theory calculations to systematically study the mobilities of different oxygen atoms on the three CeO〈sub〉2〈/sub〉 surfaces under relatively high temperatures. The O mobilities have been studied by means of MD trajectories as well as the coordination number analysis. The results indicate that the exposed unsaturated O atoms at reconstructed CeO〈sub〉2〈/sub〉(110)-2 × 1 can exhibit extraordinary mobilities, and they also suggest that besides the bonding strength, the distribution patterns of surface O atoms might be able to affect their activities as well.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): A.A. Nayl, A.I. Abd-Elhamid, Ahmed A. El-Shanshory, Hesham M.A. Soliman, El-Refaie Kenawy, H.F. Aly〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A hierarchically porous structure composite (sponge-GO) is prepared by eco-friendly and a simple immersing of a local sponge in a good dispersed GO aqueous media. Where, appropriated weight of the sponge washed several times with distilled-water and ethanol, then immersed in GO suspended solution (3 mg/mL) and left to absorb all GO suspension. The resulted sponge-GO was dried at 70 °C for 72 h. and characterized by SEM, FTIR, Raman, TGA, and EDS. The characterization results indicate that GO sheets perfectly contact with the sponge Skelton network. The fabricated sponge-GO used as a filtration device in a laboratory made continuous filter system. Methylene blue (MB) is used as a chemical contaminant in wastewater to study the adsorption ability of our system. The parameters affecting on the sorption processes as, composite dose, concentration of dye, solution pH, temperature and NaCl dose were studied. The isotherm models, Langmuir, Freundlich and Tempkin, explained that the organic contaminate prefers to adsorbed as a monolayer with high sorption efficiency q〈sub〉e〈/sub〉 = 19.60 mg g〈sup〉−〈/sup〉〈sup〉1〈/sup〉. It is evident that this filter material possesses good capability and stability. The experimental studies illustrated that sponge-GO can be reused. The breakthrough curve, Yoon–Nelson model and comparison study were also investigated.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324730-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Francielle C.F. Marcos, José M. Assaf, Reinaldo Giudici, Elisabete M. Assaf〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A mesoporous zirconia (ZrO〈sub〉2〈/sub〉) series was synthesized by reflux and hydrothermal methods using Pluronic (P-123) as a surfactant. Characterizations by XPD showed that the ZrO〈sub〉2〈/sub〉 prepared 〈em〉via〈/em〉 reflux consisted of only tetragonal crystalline phase when compared with that obtained by hydrothermal treatment, which was formed by tetragonal and monoclinic phases. The addition of the surfactant had a positive influence on the specific surface area and mesoporous structure ordering of ZrO〈sub〉2〈/sub〉, regardless of the method of synthesis. The surface interaction of H〈sub〉2〈/sub〉/CO〈sub〉2〈/sub〉 mixture with the ZrO〈sub〉2〈/sub〉 samples exhibited some dissimilarity due to the unlike surface acidic-basic features of the tetragonal and monoclinic phases. 〈em〉In-situ〈/em〉 DRIFTS experiments revealed that the species adsorbed on the zirconia prepared by the reflux method were bidentate bicarbonate, ionic bicarbonate, bidentate carbonate, and polydentate carbonate, whereas the adsorption on the zirconia prepared by refluxing method led to increased intensity of the broadband characteristic of bidentate carbonate and the appearance of two new bands typical of bidentate carbonate and bidentate bicarbonate. After subsequent switching off CO〈sub〉2〈/sub〉, it was observed that the carbonate species (1550 cm〈sup〉−〈/sup〉〈sup〉1〈/sup〉) strongly interacted with the zirconia surface and required high energy amount to be desorbed, which was in good agreement with the CO〈sub〉2〈/sub〉-TPD profile. This suggests that these carbonates are not active species when the reaction is carried out at 200 °C.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324687-ga1.jpg" width="352" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): U. Chaitra, A.V. Muhammed Ali, Alison E. Viegas, Dhananjaya Kekuda, K. Mohan Rao〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The present work explores the capability of undoped and aluminium doped zinc oxide thin films for the detection of low concentration of Sulphur dioxide gas (SO〈sub〉2〈/sub〉). Highly transparent undoped and aluminium-doped ZnO thin films were successfully deposited using sol-gel spin coating technique. The influence of various concentrations of aluminium (Al) doping on structural, morphological, optical and electrical properties has been studied. The Al doping affected the crystallinity of the films as evident from the X-ray diffraction (XRD) studies. The Atomic force microscope (AFM) and the Field emission scanning electron microscope (FESEM) studies depict the wrinkled structure of the thin films. The transparency of the deposited films was revealed by the UV–Visible characterization. Electrical characterization showed a variation in the conductivity with varying aluminium concentration which influences the gas sensing performance of the thin films. The 2 at.% aluminium doped ZnO thin films exhibited a higher sensitivity of 70% for 3 ppm of SO〈sub〉2〈/sub〉 gas which is below the threshold value limit. For comparison, NH〈sub〉3〈/sub〉 gas sensing of the grown films was also studied.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Yang Xiang, Ming Jiang, Haiyan Xiao, Kaijian Xing, Xinxin Peng, Sa Zhang, Dong-Chen Qi〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this study, a density functional theory method is employed to investigate the surface charge transfer doping of diamond by chromium trioxide (CrO〈sub〉3〈/sub〉) with high electron affinity. Superior surface charge transfer of the hydrogenated diamond surface is demonstrated using CrO〈sub〉3〈/sub〉 as an electron acceptor. The charge density difference and Bader charge analysis reveal that the electrons are transferred from the diamond surface to CrO〈sub〉3〈/sub〉 molecule, leading to the formation of two-dimensional hole gas, and the holes left in the diamond surface increase the conductivity of the diamond surface. The analysis of electronic structure indicates that areal hole density as large as 9.85 × 10〈sup〉13〈/sup〉cm〈sup〉−2〈/sup〉 for CrO〈sub〉3〈/sub〉-doped diamond surface can be achieved. Besides, the optical absorption near infrared region of the hydrogenated diamond surface is greatly enhanced upon CrO〈sub〉3〈/sub〉 doping, which implies that this CrO〈sub〉3〈/sub〉-doped diamond surface is a promising candidate for optoelectronic materials. The present study provides an in-depth theoretical understanding of the formation of two-dimensional hole gas on diamond surface induced by a new transition metal oxide, and predicts that the CrO〈sub〉3〈/sub〉-doped diamond surface may have important implications in electronic and optoelectronic devices.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324018-ga1.jpg" width="294" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Hao Lai, Jiushuai Deng, Shuming Wen〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Although dodecylamine (DDA) is a conventional collector for the flotation of smithsonite, the interaction mechanism between DDA and smithsonite is still unclear. In this study, time-of-flight secondary ion mass spectrometry (ToF-SIMS) and principal component analysis (PCA) were used to investigate the surface products of smithsonite with DDA adsorption before and after sulfidization. The spectra analysis showed that the organic peaks C〈sub〉x〈/sub〉H〈sub〉y〈/sub〉〈sup〉+〈/sup〉, CN〈sup〉−〈/sup〉, and CNO〈sup〉−〈/sup〉 dominate the spectra of the smithsonite samples, eclipsing the inorganic peaks and DDA-related peaks. PCA analysis effectively identified the spectral differences between the different samples, indicating that DDA hardly interacted with the hydrated smithsonite surface; the zinc‑sulfur complex on the sulfidized smithsonite surface existed in the form of Zn〈sub〉a〈/sub〉S〈sub〉b〈/sub〉O〈sub〉c〈/sub〉H〈sub〉d〈/sub〉; DDA was chemisorbed on the sulfidized smithsonite surface and may occur in the form of N-S-Zn, N-Zn-S, or Zn-N-S bonds.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S016943321932495X-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Rashed Md. Murad Hasan, Olivier Politano, Xichun Luo〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The nanoelectrode lithography has been strengthened in recent years as one of the most promising methods due to its high reproducibility, low cost and ability to manufacture nano-sized structures. In this work, the mechanism and the parametric influence in nanoelectrode lithography have been studied qualitatively in atomic scale using ReaxFF MD simulation. This approach was originally developed by van Duin and co-workers to investigate hydrocarbon chemistry. We have investigated the water adsorption and dissociation processes on Si (100) surface as well as the characteristics (structure, chemical composition, morphology, charge distribution, etc.) of the oxide growth. The simulation results show two forms of adsorption of water molecules: molecular adsorption and dissociative adsorption. After breaking the adsorbed hydroxyls, the oxygen atoms insert into the substrate to form the Si–O–Si bonds so as to make the surface oxidized. The influence of the electric field intensity (1.5–7 V/nm) and the relative humidity (20–90%) on the oxidation process have also been discussed. Nevertheless, the results obtained from the simulations have been compared qualitatively with the experimental results and they show in good agreements. Variable charge molecular dynamics allowed us to characterize the nanoelectrode lithography process from an atomistic point of view.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Shuai Li, Zhe Chen, Xingchen Ling, Jingjiao Cao, Qian Wang, Yu Zhou, Jun Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉High surface energy of noble metal clusters (NMCs) with sub-nanometer size (〈2 nm) endows their remarkable catalytic activity but naturally increases the risk of deactivation due to aggregation or oxidation. As a result, it is challengeable to construct efficient and stable naked NMCs. Herein, we reported the solvothermal synthesis of polyhedral oligomeric silsesquioxane (POSS) based porous ionic polymers with large surface areas, tunable pore structures and abundant ionic sites that resemble the structure of traditional ionic liquids. A series of highly dispersive and stable NMCs (Pd, Pt, Ru and Rh) were generated on these polymers by modulating their polyoxometalate (POM) anions, attributable to their robust framework and ion-exchange property. These organic cations paired POM anions are found to provide versatile strong interaction towards noble metal species, responsive for the formation and stabilization of NMCs. The obtained Pd clusters effectively catalyzed the solvent-free oxidation of benzyl alcohol with atmospheric dioxygen (O〈sub〉2〈/sub〉), affording a high yield of 97% and a huge turnover number (TON) that exceeded 639 times of commercial Pd/C catalyst. The catalyst also exhibited pleasurable reusability and broad substrate compatibility.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S016943321932447X-ga1.jpg" width="301" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Zhen Niu, Tong Yue, Wenjihao Hu, Wei Sun, Yuehua Hu, Zhenghe Xu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Graphene/α-MnO〈sub〉2〈/sub〉 nanocrystals hybrid aerogel (GMA) was designed for catalytic ozonation of rhodamine B (RhB) solution in this study. A novel method was proposed to synthesize this hybrid aerogel in an isopropanol-water system, in contrast to the conventional reaction of potassium permanganate with graphene aerogel, which destroyed the desired structure of graphene. Characterization of the synthesized GMA was carried out by XRD, SEM, TEM, Raman, and BET. It was found that GMA had a porous structure and the needle-like α-MnO〈sub〉2〈/sub〉 nanocrystals were doped in the graphene aerogel uniformly. Based on the FTIR and XPS analysis, the α-MnO〈sub〉2〈/sub〉 was found to covalently bond with graphene aerogel. The removal efficiency of both RhB and COD was found to be in the following order of Blank〈 GA 〈 SMA (silica wool with nano MnO〈sub〉2〈/sub〉 deposited on it) 〈 GMA(I) 〈 GMA(II) 〈 GMA(III). The degradation rate constant (〈em〉k〈/em〉) of RhB ozonation catalyzed by GMA was determined to be 1.2–2.3 times higher as compared with that by UV/Ozone. The enhanced catalytic activity of GMA could be attributed to the high dispersibility of the α-MnO〈sub〉2〈/sub〉 nanocrystals on graphene and the abundant mesopores (r 〈 40 nm) in GMA. The higher electron cloud density of the Mn atoms, when supported by graphene aerogel, promoted the generation of HO〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/rad"〉 radicals, thereby resulting in better decomposition performance of GMA than UV/Ozone systems.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219323827-ga1.jpg" width="311" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Min Zheng, Lei Wei, Jing Chen, Qiang Zhang, Jiaqiang Li, Shang Sui, Geng Wang, Weidong Huang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A novel physical model for the selective laser melting (SLM) was proposed, providing insights into the surface morphology evolution in the pulsed SLM process. Both Marangoni effect and recoil pressure, which were the prevailing driving forces for the melt flow, were incorporated in the model. It was found that the melt track was characterized by regular fish scale patterns in pulsed remelting process, due to the periodic variation of the molten pool, while the melt track exhibited with a smooth surface under a continuous laser mode. The effect of the exposure time on the surface morphology was also investigated during pulsed SLM process. It was shown that the longer exposure time could produce greater recoil pressure and sufficient molten liquid, leading to a more congested fish scale patterns. The surface defects such as distortions and breakups were strongly associated with the distribution characteristics of the powders. The partially melted particles which attached to the melt flow were the main reasons to the formation of distortions. And the formation the breakups could be attributed to the local lacking of the powders. The simulated results were in good agreement with the experimental results.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 494〈/p〉 〈p〉Author(s): Yunhui Wang, Qiang Wu, Jianing Mao, Shuixin Deng, Rui Ma, Jiaoyan Shi, Jiaoyang Ge, Xin Huang, Lan Bi, Jie Yin, Shanling Ren, Gang Yan, Zhihong Yang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Recently, a novel layered two-dimensional carbon nanomaterial was synthesized named triphenylene-graphdiyne (TpG). The acetylenic ring and triphenylene are included in primitive cell of this structure. In this work, many different strategies have been adopted to investigate hydrogen storage capacity of Li- and Ca-decorated pristine and B-doped TpG by first-principles calculations. The maximum three H〈sub〉2〈/sub〉 molecules are captured around every one Li atom by Li-decorated on the acetylenic ring only for TpG. The hydrogen storage gravimetric capacity of 8.17 wt% with an approximate ideal average H〈sub〉2〈/sub〉 adsorption energy of 0.18 eV/H〈sub〉2〈/sub〉. Moreover, both acetylenic ring and triphenylene are decorated by Li and two H〈sub〉2〈/sub〉 molecules are adsorbed for each Li atom. The hydrogen storage capacity reaches to 9.70 wt% with an ideal average hydrogen adsorption energy of 0.27 eV/H〈sub〉2〈/sub〉. After two C atoms are doped by B atoms, two more Li atoms are introduced to the triphenylene. Here, maximum 20 H〈sub〉2〈/sub〉 molecules are adsorbed on Li-decorated B-doped TpG. The hydrogen storage capacity reaches to 8.77 wt%, with ideal average hydrogen adsorption energy of 0.24 eV/H〈sub〉2〈/sub〉. Four H〈sub〉2〈/sub〉 molecules can be adsorbed effectively by Ca-decorated pristine TpG with the average hydrogen adsorption energy of 0.19 eV/H〈sub〉2〈/sub〉. We also calculated the H〈sub〉2〈/sub〉 storage of Ca-decorated B-doped TpG and 5.51 wt% of gravimetric with ideal average hydrogen adsorption energy of 0.25 eV/H〈sub〉2〈/sub〉 can be obtained. Our calculation indicates that the Li- and Ca-decorated B-doped TpG and Li-decorated pristine TpG can be a very promising material for reversible hydrogen storage.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219322366-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 494〈/p〉 〈p〉Author(s): Jin Wang, Long Fan, Xuemin Wang, Tingting Xiao, Liping Peng, Xinming Wang, Jian Yu, Linhong Cao, Zhengwei Xiong, Yajun Fu, Chuanbin Wang, Qiang Shen, Weidong Wu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The properties of graphene vary with the number of layers, thus determining its usefulness in different applications. Consequently, it is important to develop a method for precisely controlling the number of layers for various application demands. In this study, high quality monolayer graphene was successfully prepared using pulsed laser deposition. Meanwhile, the growth of monolayer and bilayer graphene can be controlled by adjusting the laser energy density. Raman spectra show that high quality monolayer films grew at a laser energy density of 5.66 J/cm〈sup〉2〈/sup〉 and bilayer graphene films grew at a laser energy density of 8.49 J/cm〈sup〉2〈/sup〉. X-ray photoelectron spectroscopy indicate that the main chemical state of carbon is the sp〈sup〉2〈/sup〉 hybrid state, and the maximum atomic ratio of sp〈sup〉2〈/sup〉 and sp〈sup〉3〈/sup〉 results from the sample with laser energy density of 5.66 J/cm〈sup〉2〈/sup〉. Scanning electron microscope images show that monolayer graphene is connected by small sheets with different sizes, and the largest graphene sheet reaches 20 μm. High resolution transmission electron microscope images and selected area electron diffraction patterns show that graphene samples are highly crystalline and yield significant layer information. UV–Vis spectra indicate that the transmittance through monolayer and bilayer graphene at 550 nm are 96.93% and 95.05%, respectively. Ultraviolet photoelectron spectroscopic measurements show that the work function of graphene ranges from 3.72 eV to 4.76 eV; the variation in the work function is related to growth defects. Finally, the relationship between the structure of the graphene films and laser energy density are investigated in detail, and these results indicate that the controllable growth of graphene can be achieved by adjusting the laser energy density. This means that a suitable laser energy density is conducive to defining an equilibrium between diffusion and condensation of carbon atoms, which is crucial to the growth of high-quality monolayer and bilayer graphene. It is expected that this study might be facilitate the preparation of graphene-based composite films and devices.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219322123-ga1.jpg" width="221" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 494〈/p〉 〈p〉Author(s): Yuxiang Wang, Qianqian Shangguan, Dingni Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The droplet anisotropic wetting on chemically heterogeneous stripe-patterned substrates after impact is studied by using many-body dissipative particle dynamics in this work. After a low-velocity impact on substrates with different length ratio (ratio of stripe width to the initial droplet size) and Cassie area fraction, the droplet can show various shapes and contact angles in parallel and orthogonal directions to the stripes. The elongation of the droplet can be increasingly evident when increasing the length ratio. Also, the contact angles at both directions follow the Cassie-Baxter predicted values well at low length ratio while deviate from them at high length ratio. Both the capillary and kinetic effects have a significant influence on the anisotropic wetting. When impact with higher velocity, the droplet leaves some residues on the hydrophilic stripes of the substrates. Surprisingly, the residues for substrates with certain length ratio (≤0.316) are distributed in circular regions with almost identical radii, indicating the spreading stages of them are independent on the surface properties and dominated by the kinetic effect. When the droplet reaches a stable state, the main body shows anisotropic wetting behavior, indicating the capillary effect dominates the wetting instead of the kinetic effect at the retraction stage.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219322494-ga1.jpg" width="282" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 494〈/p〉 〈p〉Author(s): Peiman Xu, Jinming Zhang, Zhifeng Ye, Yiyi Liu, Tianlun Cen, Dingsheng Yuan〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Tailoring low-cost electrocatalysts with high activity and good stable for hydrogen evolution reaction (HER) is vital to energy harvesting and storage. Herein, Co doped Ni〈sub〉0.85〈/sub〉Se nanoparticles supported on reduced graphene oxide (Co〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉Ni〈sub〉0.85〈/sub〉Se/RGO) were synthesized by a facile one-step hydrothermal method. As expected, the resulting hybrid materials effectively inhibit the aggregation of nanoparticles and possess the enhanced intrinsic conductivity, leading to exposure of more active sites and the faster electron transport. And then these beneficial effects enable Co〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉Ni〈sub〉0.85〈/sub〉Se/RGO efficient HER catalytic activity in both acid and basic electrolytes, achieving small overpotentials of 148 and 128 mV at a current density of 10 mA cm〈sup〉−〈/sup〉〈sup〉2〈/sup〉 in 0.5 M H〈sub〉2〈/sub〉SO〈sub〉4〈/sub〉 and 1.0 M KOH, respectively.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219322676-ga1.jpg" width="327" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 494〈/p〉 〈p〉Author(s): Xuefei Wang, Jingchao Yu, Can Fu, Tianyi Li, Huogen Yu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Composite semiconductor photocatalysts with hollow structures can present excellent photocatalytic performance by combining the advantages of composite photocatalyst and hollow structures. However, it is a great challenge to develop a facile synthetic route to realize the composite hollow nanostructures. In the paper, AgCl/TiO〈sub〉2〈/sub〉 composite hollow octahedra were synthesized by a facile self-templated method via the direct addition of Ag〈sub〉2〈/sub〉O octahedron template into TiCl〈sub〉4〈/sub〉 ethanol solution. In the case, AgCl and TiO〈sub〉2〈/sub〉 nanoparticles can be simultaneously formed to construct the shell of hollow octahedra along with the alcoholysis and hydrolysis of TiCl〈sub〉4〈/sub〉 and the reaction of releasing H〈sup〉+〈/sup〉 and Cl〈sup〉−〈/sup〉 ions with Ag〈sub〉2〈/sub〉O template. Obviously, the synthetic method showed some advantages of economic reaction steps and uniform component distribution. After AgCl/TiO〈sub〉2〈/sub〉 is illuminated by visible light, partial Ag metal can form in the sample due to the photosensitive property. Further photocatalytic results indicated that the Ag/AgCl/TiO〈sub〉2〈/sub〉 hollow octahedron photocatalyst exhibited excellent photocatalytic activity and stability of performance. Importantly, the present Ag〈sub〉2〈/sub〉O self-template method was also extended for the synthesis of other hollow octahedra such as AgCl/Bi〈sub〉2〈/sub〉O〈sub〉3〈/sub〉, AgCl/SnO〈sub〉2〈/sub〉 and AgCl. Thus, the present work may provide new insights into design and synthesis of other hollow octahedron photocatalysts.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219322573-ga1.jpg" width="479" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 494〈/p〉 〈p〉Author(s): Ling Zhang, Xijian Liu, Min Zhang, Haikuan Yuan, Lijuan Zhang, Jie Lu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We present here a novel, simple, low cost and green synthetic strategy for unique core-shell structured Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉@C-MoO〈sub〉2〈/sub〉-Ni composites without using extra reducing agent. The Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉@C-MoO〈sub〉2〈/sub〉-Ni composites exhibited better catalytic performance (reduction of 4-nitrophenol to 4-aminophenol) than previous common catalysts because highly dense satellite Ni nanoparticles firmly distributed on the porous carbon spheres. In addition, the Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉@C-MoO〈sub〉2〈/sub〉-Ni composites can be used as a pollutant remover due to fast adsorption rate and high adsorption capacity for dye in water. More importantly, owing to high magnetic susceptibility, the Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉@C-MoO〈sub〉2〈/sub〉-Ni composites show excellent performance for recyclable use by magnetic separation. Thus, the Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉@C-MoO〈sub〉2〈/sub〉-Ni composites have great potential as an ideal catalyst and adsorbent due to facile and green synthesis method, good stability, excellent recyclability, nontoxic and low cost properties.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219322925-ga1.jpg" width="301" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 494〈/p〉 〈p〉Author(s): Xingwen Zhou, Wei Guo, Jian Fu, Ying Zhu, Yongde Huang, Peng Peng〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Efficient manufacturing of composite structure is one of the key challenges in the fabrication of flexible devices. Laser direct writing provides a solution due to its area selectivity, controllability and rapid processing. In this study, one-step patterning of Cu/Cu〈sub〉〈em〉x〈/em〉〈/sub〉O structure with tunable composition on flexible substrate has been realized with laser direct writing on Cu precursor film. An integrated humidity sensor that combines a Cu〈sub〉〈em〉x〈/em〉〈/sub〉O-rich porous sensing structure with a conductive Cu-rich structure has been fabricated. The one-step-written device showed high sensitivity to human breathing. This work highlights the promise of this one-step mask-less laser writing as an efficient, rapid and low-cost composite structure fabrication process for flexible devices.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219321956-ga1.jpg" width="415" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 494〈/p〉 〈p〉Author(s): Mehdi D. Esrafili, Mehdi Vatanzadeh〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A dispersion-corrected density functional theory study is performed about reaction pathways and energy barriers of NO reduction by CO over Si-coordinated nitrogen doped graphene (SiN〈sub〉4〈/sub〉-Gr). The results indicate that NO molecule can be stably chemisorbed over the Si atom of SiN〈sub〉4〈/sub〉-Gr due to the favorable hybridization of Si-3p and NO-2π* states. The coadsorption of NO molecules to form absorbed (NO)〈sub〉2〈/sub〉 species is proved to be the initial step for the reduction of NO molecules over the title surface. The energy barriers for the (NO)〈sub〉2〈/sub〉 → N〈sub〉2〈/sub〉O + O* reaction are in the range of 0.38–0.60 eV, which seem to be overcome at ambient condition. According to our findings, NO reduction over SiN〈sub〉4〈/sub〉-Gr is a thermodynamically favored process at a relatively wide range of temperatures.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219322536-ga1.jpg" width="265" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 494〈/p〉 〈p〉Author(s): Youssef Berro, Saber Gueddida, Sébastien Lebègue, Andreea Pasc, Nadia Canilho, Mounir Kassir, Fouad El Haj Hassan, Michael Badawi〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The upgrading of lignin-derived bio-oils involves a HydroDeOxygenation (HDO) reaction through either the Hydrogenation (Hyd) or the Direct DeOxygenation (DDO) route, the latter limiting hydrogen consumption. Herein, dispersion-corrected DFT has been used to evaluate the adsorption behavior of phenol (as a representative model of bio-oils) and two by-products (water and CO) over various crystalline and amorphous silica surfaces to evaluate their potential selectivity (DDO/Hyd) and efficiency (low inhibiting effect) for HDO processing. Phenol can adsorb through three modes, flat π-interaction, flat O-interaction or perpendicular O-interaction. All crystalline surfaces show a preference for the flat π-interaction, which is expected to promote the Hyd route. Over amorphous surfaces the flat O-interaction dominates, and a very specific and strong interaction (around −120 kJ/mol) was found on SiO〈sub〉2〈/sub〉-3.3 and SiO〈sub〉2〈/sub〉-2.0 surfaces where the phenol molecule loses its aromaticity, which is very promising for its degradation under catalytic conditions. In addition, this makes those surfaces very efficient to adsorb selectively phenol in presence of water and CO. Remarkably, on all silica surfaces, the interaction energy of CO is nearly negligible, which makes them more attractive for HDO process compared to sulfide catalysts with respect to the inhibiting effect criteria.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉High adsorption selectivity of phenol vs CO and H〈sub〉2〈/sub〉O on amorphous silica.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219322524-ga1.jpg" width="237" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 494〈/p〉 〈p〉Author(s): A.C. Bouali, E.A. Straumal, M. Serdechnova, D.C.F. Wieland, M. Starykevich, C. Blawert, J.U. Hammel, S.A. Lermontov, M.G.S. Ferreira, M.L. Zheludkevich〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This work reports a novel approach for growing layered double hydroxide (LDH) films on any plasma electrolytic oxidation (PEO) coated AA2024 independently of the nature of the PEO coating. The specific PEO coating chosen to carry out this work is considered to be not suitable for direct LDH growth because of phase composition and morphological features. In this paper, we describe a new methodology that consists of covering the PEO coating with a thin layer of aluminum oxide based xerogel as the source of aluminate ions for subsequent in-situ LDH growth. X-ray diffraction (XRD) and scanning electron microscope (SEM) images showed a successful formation of LDHs on the surface. An improvement in terms of active corrosion protection was also demonstrated by electrochemical impedance spectroscopy (EIS) and scanning vibrating electrode technique (SVET).〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219321531-ga1.jpg" width="473" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 494〈/p〉 〈p〉Author(s): M.S.M. Shukri, M.N.S. Saimin, M.K. Yaakob, M.Z.A. Yahya, M.F.M. Taib〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The effect of CO and NO adsorption on graphene (pristine, vacancy and doped) were investigated for structural and electronic properties. The sensitivity of palladium (Pd) doped graphene toward small gas molecules CO and NO have been investigated by using DFT calculation within Generalized Gradient Approximation (GGA) as implemented in DMol〈sup〉3〈/sup〉 and CASTEP. The density of states, the most stable adsorption site and adsorption energy of these small gas molecules on vacancy graphene and Pd-doped vacancy graphene are thoroughly discussed. It is found that Pd doping significantly enhances the strength of interaction between adsorbed molecules and the modified substrates. The most stable adsorption site for CO and NO on all graphene sheets are identified and reported. The results present the potential of vacancy graphene and Pd-doped vacancy graphene for molecules sensor application.〈/p〉〈/div〉 〈div〉 〈h6〉Novelty〈/h6〉 〈p〉〈/p〉 〈dl〉 〈dt〉•〈/dt〉 〈dd〉〈p〉The novelty of this paper is the doping of Pd on vacancy graphene surface could enhance the adsorption energy of CO and NO gas molecules.〈/p〉〈/dd〉 〈dt〉•〈/dt〉 〈dd〉〈p〉Besides, most of the studies not using Pd on vacancy graphene to study its effect on small molecules.〈/p〉〈/dd〉 〈/dl〉 〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219322743-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 494〈/p〉 〈p〉Author(s): Li Quan, Xuelian Yu, Tao Wang, Wenchao Yin, Jianqiao Liu, Lin Wang, Yihe Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The rational design of non-noble-metal electrocatalysts for oxygen reduction reaction (ORR) with both excellent activity and robust stability still remains a key challenge nowadays. Herein, N-doped carbon wrapped Co nanoparticles core-shell nanostructures grafted on carbon nanotubes (Co@NC@CNTs) were achieved by a simple pyrolysis process using ZIF-67 and CNTs as precursors. Most importantly, this unique structure of Co@NC@CNTs is beneficial to increase the contact area of N-doped carbon and Co, inhibit the aggregation of Co@NC core-shell nanoparticles and protect the Co from dissolution, thus improving the electrocatalytic performance and stability for ORR. As a result, the well-defined Co@NC@CNTs electrocatalyst exhibits excellent ORR activity with a high onset potential, half-wave potential and limited current density, comparable to the commercial Pt/C in alkaline electrolyte. Furthermore, the Co@NC@CNTs electrocatalyst presents outstanding electrochemical durability and methanol tolerance in comparison with Pt/C. This strategy will open a new avenue toward the development of nonprecious high-performance ORR catalysts.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219321932-ga1.jpg" width="410" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Yong Nam Ahn, Sung Hoon Lee, Sang Yoon Oh〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The adsorption mechanism and the structural features of perfluoropolyether (PFPE)-containing layers from silane-functionalized derivate (SPFPE) on hydroxylated glassy silica surfaces are systematically investigated by utilizing density functional theory and molecular dynamics simulations. It is found that each individual SPFPE molecule tends to be chemisorbed on the silica surface by forming a single siloxane bond regardless of the number of reactive branches in the functional end group of the SPFPE molecules. We also reveal that the formation of multiple siloxane bonds between a single SPFPE molecule and the hydroxylated silica surfaces is hindered by not only the constraint on geometrical optimization of the absorbed molecule but also the pre-existing hydrogen bonds between adjacent hydroxyl groups on the surfaces. With a structural analysis, the adsorption orientation of SPFPE molecules is predicted as parallel to the silica surface, which induces low surface coverage (~0.31 molecules/nm〈sup〉2〈/sup〉) and sub-nano thickness (~8 Å) of the absorbed PFPE-containing layer. These adsorption characteristics are distinct from those of self-assembled monolayers consisting of fluorocarbon or hydrocarbon molecules. We believe that the fundamental understanding of adsorption mechanism and molecular morphology of the PFPE-containing layers demonstrated in this study can contribute to developing new advanced anti-fouling materials with improved mechanical property.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324961-ga1.jpg" width="456" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): K. Niranjan, P. Kondaiah, G. Srinivas, Harish C. Barshilia〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A novel spectrally selective tandem stack of W/WAlSiN/SiON/SiO〈sub〉2〈/sub〉 was deposited on stainless steel 304 and silicon substrates using a four-cathode reactive unbalanced magnetron sputtering system. The coatings were deposited by sputtering of W, Al and Si targets in Ar, Ar + N〈sub〉2〈/sub〉, Ar + N〈sub〉2〈/sub〉 + O〈sub〉2〈/sub〉, and Ar + O〈sub〉2〈/sub〉 plasmas. The process parameters were optimized by studying the optical properties of the individual layers using UV-VIS-NIR spectrophotometer and Fourier transform infrared spectroscopy measurements. The high spectral selectivity of the tandem stack was achieved by varying the reactive gas flow rates of N〈sub〉2〈/sub〉 and O〈sub〉2〈/sub〉 and thickness of individual layers. In the tandem stack, W layer acts as an IR reflector, WAlSiN acts as the main absorber layer, SiON, and SiO〈sub〉2〈/sub〉 layers act as anti-reflecting layers. The tandem stack was designed based on graded refractive indices of individual layers with a double layer anti-reflection coating. The tandem stack exhibits superior spectral selectivity with a high solar absorptance of 0.955 in the broadband solar spectrum region and low thermal emissivity of 0.10 in the infrared region. The coating was found to be thermally stable up to 600 °C in vacuum for 200 h under cycling heating conditions.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Xiaoshuo Liu, Zhengyang Gao, Cheng Wang, Mingliang Zhao, Xunlei Ding, Weijie Yang, Zhao Ding〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉As important parts of simultaneous removal of multiple pollutants in flue gas, catalytic oxidation of Hg〈sup〉0〈/sup〉 and adsorption removal of SO〈sub〉3〈/sub〉, Pb species and As〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 on the surface of (Fe,Co)@N-GN catalyst were systematically investigated in this work, using density functional theory. As a result, we found (Fe,Co)@N-GN not only showed great performance on Hg〈sup〉0〈/sup〉 oxidation, but also exhibited outstanding removal capacity for SO〈sub〉3〈/sub〉, Pb species and As〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 molecules. Besides, PDOS and EDD analysis were carried out and the result indicated that electron transfer and orbit hybridization played key roles in gas adsorption. In addition, thermodynamics analysis further evidenced (Fe,Co)@N-GN was a qualified sorbent under 550 K, and competitive analysis suggested that the adsorption order of pollution gas was determined by adsorption energy, rather than the volume fraction of corresponding gases in flue gas. We hoped this work can not only lay a foundation for theoretical investigation of Hg〈sup〉0〈/sup〉 oxidation, but also provide an important guideline for simultaneous removal of multiple pollutants released from coal-fired power plants.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324833-ga1.jpg" width="254" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Zhigang Mou, Hui Zhang, Zeman Liu, Jianhua Sun, Mingshan Zhu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Photocatalysis, as a green chemical technology for the removal of antibiotics, has attracted great interest recently. This study proposed a facile one-step hydrothermal process to fabricate ultrathin two dimensional (2D) BiOCl/nitrogen-doped graphene quantum dots (BiOCl/NGQDs) composites. Compared to pure BiOCl, the BiOCl/NGQDs composites exhibited enhancement in both adsorption and photodegradation for antibiotic ciprofloxacin (CIP). The optimized content of NGQDs was 6.9% and this optimized composite showed a degradation efficiency of 82.5% within 60 min under visible-light irradiation, which was considerably better than that of pure BiOCl (34.9%). Meanwhile, most of CIP was efficiently mineralized into CO〈sub〉2〈/sub〉, H〈sub〉2〈/sub〉O and other inorganic products, as revealed by a total organic carbon (TOC) removal efficiency of 95.5% within 5 h. The improved photocatalytic activity was attributed to excellent adsorption capability, enhanced visible-light response and efficient separation of the photoinduced electron-hole pairs in BiOCl/NGQDs composite. The active species trap experiments and electron spin resonance revealed that 〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/rad"〉O〈sub〉2〈/sub〉〈sup〉−〈/sup〉 and hole mainly participated in the CIP degradation process. Such an effective strategy to design ultrathin 2D composite photocatalysts would provide a new approach for application in wastewater purification.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324523-ga1.jpg" width="371" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Iwan Susanto, Chi-Yu Tsai, Fachruddin, Tia Rahmiati, Yen-Ten Ho, Ping-Yu Tsai, Ing-Song Yu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In the report, the growth of GaN films on the two-dimension molybdenum disulfide (2D MoS〈sub〉2〈/sub〉) and c-sapphire 〈em〉via〈/em〉 plasma-assisted molecular beam epitaxy (MBE) was investigated. Two kinds of MoS〈sub〉2〈/sub〉 layers were prepared by pulsed laser deposition (PLD) and chemical vapor deposition (CVD) techniques. Three different surface conditions were designed for the growth of GaN films. GaN thin films in the form of polycrystalline were successfully grown on the surface of MoS〈sub〉2〈/sub〉 layers. From the surface analysis, CVD technique provided an amorphous and rougher MoS〈sub〉2〈/sub〉 surface for the MBE growth. On the contrary, PLD supplied a better in-plane and smoother surface for GaN growth which included more stability of surface chemical composition, higher crystallinity and better near-band-edge emission property. To compare with the growth on c-Sapphire, however, the van der Waals expitaxial growth of single-crystalline GaN films on sp〈sup〉2〈/sup〉 bonded 2D MoS〈sub〉2〈/sub〉 is still a challenge. The growth of GaN films on sp〈sup〉3〈/sup〉 bonded c-sapphire still performed the best results in the report. In summary, we demonstrate better growth of GaN thin films on 2D MoS〈sub〉2〈/sub〉 surface provided by PLD. The hetetrostructure of 3D GaN on 2D MoS〈sub〉2〈/sub〉 semiconductors could be useful in the future applications of electronic and optoelectronic devices.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Kyung Pyo Hong, Kyu Hyun Lee, Jungtae Nam, Kyoung Soo Kim, Sung Hee Kim, Boram Kim, Kisoo Kim, Jin Sung Park, Jun Young Lee, Taehwan Jeong, Young Jae Song, Jun Yeon Hwang, Jae Boong Choi, Seungmin Cho, Keun Soo Kim, Hyeongkeun Kim〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The present study investigates the atomic layer deposition (ALD) of an Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 film on graphene atop copper with water vapor (H〈sub〉2〈/sub〉O), oxygen plasma (O〈sub〉2〈/sub〉 plasma) and ozone (O〈sub〉3〈/sub〉) serving as oxidants. With water vapor as an oxidant, surface-sensitive deposition results in significant differences in growth on single layer graphene (SLG) and multilayer graphene (MLG). Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 completely covers areas of SLG, while virtually no Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 is deposited on areas of MLG. The MLG areas are removed by O〈sub〉2〈/sub〉 plasma, and exposed copper areas are oxidized. Information about MLG, including the location, size, and density, can be determined by employing optical microscopy. Scanning electron microscopy (SEM), Raman spectroscopy, transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) are used to confirm the validity of the surface-selective deposition of Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 on graphene grown on copper. We developed a process to distinguish SLG and MLG on copper. The characterization results were fed back to the synthesis conditions, and we confirmed that high-quality SLG can be grown on copper almost devoid of MLG. This characterization technique is suitable for large-area graphene (up to meter scale graphene), and can be utilized as feedback for growth and process conditions to ensure high-quality graphene.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324110-ga1.jpg" width="380" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Jae-Yup Kim, Woonhyuk Baek, Soyoung Kim, Gumin Kang, Il Ki Han, Taeghwan Hyeon, Minwoo Park〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Extensive studies have been performed to improve the environmental stability of perovskite solar cells (PSCs) with the use of inorganic charge transport layers (CTLs). However, for 〈em〉n〈/em〉-i-〈em〉p〈/em〉 structures, it is difficult to deposit 〈em〉p〈/em〉-type inorganic nanocrystals onto perovskites to form the CTLs because they are usually prepared in polar solvents. In this regard, hydrophobic nanoparticles dispersed in nonpolar solvents would be beneficial for their deposition onto the perovskites, thus leading to the formation of a hole transport layer (HTL). In this work, we report on the preparation of monodispersed CuIn〈sub〉1.5〈/sub〉Se〈sub〉3〈/sub〉 (CISe) quantum dots (QDs) (diameter = 4 nm) for the design of PSCs based on all-inorganic CTLs. By means of efficient hole injection and transfer process through the CISe-HTLs, impressive power conversion efficiencies (PCEs) of 13.72% and 12.19% for active areas of 0.12 cm〈sup〉2〈/sup〉 and 1.0 cm〈sup〉2〈/sup〉 are achieved, respectively, and the devices exhibit hysteresis-less behaviors. Furthermore, the devices show excellent PCE retentions of 89.2% and 74.9% after 30 d relative to their initial values at relative humidity of 25% and 50%, respectively. The hydrophobic QDs effectively suppress the penetration of moisture such that the device maintains its stability in humid environments.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Mohammad Amin Razmjoo Khollari, Mohammad Ghorbani, Abdollah Afshar〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Preparing a selective, efficient, and low-cost solar absorber is one of the main challenges in solar to thermal energy conversion. In this paper, black electroless Ni〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉P (ENi-P) solar absorber has been fabricated, and the effect of nanoporous TiO〈sub〉2〈/sub〉 antireflection layer (ARL) on its optical and corrosion properties has been investigated. The optimum black coating was obtained by blackening in 9 M nitric acid solution at 50 °C for 40 s, in which a solar absorptance of 99.3% was achieved. Deposition of TiO〈sub〉2〈/sub〉 ARL increased the solar absorptance of coating to 99.7% and addition of 0.8 g Pluronic F127 (F127) as pore former, further increased this value to 99.9% and solar-to-heat efficiency of the coating from 78.1 to 78.7%. F127 added coatings exhibited elongated and irregularly shaped pores with dimensions of a few tens of nanometers. Also, deposition of TiO〈sub〉2〈/sub〉 ARL decreased the corrosion current density (i〈sub〉corr〈/sub〉) of black ENi-P coating in 3.5 wt% NaCl solution from 20 to 4 μA/cm〈sup〉2〈/sup〉. The results of this work indicate that the TiO〈sub〉2〈/sub〉 deposited black ENi-P coating can be a suitable choice for black coating applications.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉Reduction in unwanted light reflection from black ENi-P solar absorber by deposition of TiO〈sub〉2〈/sub〉 ARL that leads to increase in solar-to-heat conversion efficiency.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324298-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Leijie Sun, Manman Ding, Jie Li, Li Yang, Xun Lou, Zijian Xie, Wenfeng Zhang, Haixin Chang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Two dimensional layered materials show great potential in memristor applications. MoTe〈sub〉2〈/sub〉 shows unique properties and is an important 2D material. However, MoTe〈sub〉2〈/sub〉- based memristor has been rarely studied so far. Herein, a facile method is developed to control phase in large area MoTe〈sub〉2〈/sub〉 and MoTe〈sub〉2-x〈/sub〉O〈sub〉x〈/sub〉/MoTe〈sub〉2〈/sub〉 heterostructures by precursor thickness in chemical vapor deposition. The memristive behavior of MoTe〈sub〉2〈/sub〉 is highly influenced by phase and oxidization states in MoTe〈sub〉2-x〈/sub〉O〈sub〉x〈/sub〉/MoTe〈sub〉2〈/sub〉 heterostructures. The original 2H and 1 T’ MoTe〈sub〉2〈/sub〉 doesn't have memristive property while the surface oxidized 2H-MoTe〈sub〉2〈/sub〉 based MoTe〈sub〉2-x〈/sub〉O〈sub〉x〈/sub〉/MoTe〈sub〉2〈/sub〉 heterostructures behave excellent and stable memristive behavior for at least 3000 cycles. 1 T’ -MoTe〈sub〉2〈/sub〉 based heterostructures still show no memristive behavior. In addition, we compare the effect of metal electrode (Ag electrode and Al electrode) on heterostructures based memristor. The pulse tests about memristor from oxidized 2H-MoTe〈sub〉2〈/sub〉 based heterostructures show a good mimic of biological synapses in neuromorphic system.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 16 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science〈/p〉 〈p〉Author(s): Jariyanee Prasongkit, Vivekanand Shukla, Anton Grigoriev, Rajeev Ahuja, Vittaya Amornkitbamrung〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Recent significant advancements have been made in demonstrating the usage of phosphorene to detect the presence of gases leading to a new breed of gas sensor devices. Based on pristine phosphorene, the devices can detect a small concentration of adsorbed molecules with high sensitivity at room temperature. In this work, we propose doping silicon and sulfur impurity atoms into phosphorene to drastically improve its gas sensing performance. We use a combination of density functional theory and non-equilibrium Green's function method to evaluate the sensitivity and selectivity of doped phosphorene nanosensors for four gases (NO, NO〈sub〉2〈/sub〉, NH〈sub〉3〈/sub〉, and CO). Both devices demonstrate a prominent distinction in conductance when the gas molecules are exposed to the sensor surface. We suggest the doped phosphorene may present advantages over the device based purely on phosphorene due to the ability to discriminate different gases controlled by types of dopants.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324572-ga1.jpg" width="478" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Zhufeng Hu, Wenchao Peng, Wen Tian, Feifei Wang, Xin Kang, Yu Xin Zhang, Hairong Yue, Lili Zhang, Junyi Ji, Shaobin Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Rational construction of three-dimensional (3D) porous carbon nanotubes (CNTs) hierarchical architectures can provide diverse frameworks for fabrication of functionalized electrodes to effectively enhance their electrochemical performance. In this paper, a modified electroless deposition (ELD) process for uniformly anchoring of Ni@Pd seeds on substrates is reported. The tightly immobilized bi-metal seeds without aggregation during annealing leads to 〈em〉in-situ〈/em〉 growth of uniform intertwined CNTs arrays. The ELD seeding and CNTs growth method was successfully applied on different 3D carbon- and metal- based substrates. The 3D interconnected CNTs/carbon composites offer a hierarchical micro-/nano- network to facilitate electrolyte infiltration, while the CNTs arrays can effectively improve the electrical conductivity and enlarge the active surface area of the hybrids substrate. The hierarchical hybrid electrodes exhibit enhanced electrochemical performance in electrocatalysis and as a supercapacitor. The ELD process can be a general and scalable strategy for industrialized fabrication of any 3D carbon-based substrate and will be much promising in the applications of energy storage and conversion.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219325012-ga1.jpg" width="301" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 16 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science〈/p〉 〈p〉Author(s): Xiaowen Ruan, Hao Hu, Guangbo Che, Pengjie Zhou, Chunbo Liu, Hongjun Dong〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this study, an efficient and durable photocatalyst composed of Bi〈sub〉12〈/sub〉GeO〈sub〉20〈/sub〉 and γ-Bi〈sub〉2〈/sub〉MoO〈sub〉6〈/sub〉 through like 〈em〉Z〈/em〉-scheme mechanism was successfully obtained by heat treatment. The as-prepared Z-scheme 40γ-Bi〈sub〉2〈/sub〉MoO〈sub〉6〈/sub〉/Bi〈sub〉12〈/sub〉GeO〈sub〉20〈/sub〉 heterostructure presents the superior photocatalytic performance for degrading MBT, which is nearly 46 and 4.95 times higher than that of the pure Bi〈sub〉12〈/sub〉GeO〈sub〉20〈/sub〉 (〈em〉k〈/em〉〈sub〉app〈/sub〉 = 0.0007 min〈sup〉−1〈/sup〉) and Bi〈sub〉2〈/sub〉MoO〈sub〉6〈/sub〉 (〈em〉k〈/em〉〈sub〉app〈/sub〉 = 0.0065 min〈sup〉−1〈/sup〉), respectively. Meanwhile, the 40γ-Bi〈sub〉2〈/sub〉MoO〈sub〉6〈/sub〉/Bi〈sub〉12〈/sub〉GeO〈sub〉20〈/sub〉 heterostructure also shows the quite high photocatalytic performance for degrading TC, which is approximately 5.48 and 1.89 times higher than that of the pure Bi〈sub〉12〈/sub〉GeO〈sub〉20〈/sub〉 (〈em〉k〈/em〉〈sub〉app〈/sub〉 = 0.0021 min〈sup〉−1〈/sup〉) and Bi〈sub〉2〈/sub〉MoO〈sub〉6〈/sub〉 (〈em〉k〈/em〉〈sub〉app〈/sub〉 = 0.0061 min〈sup〉−1〈/sup〉), respectively. The enhancement of photocatalytic performance originates from not only the strong interface between Bi〈sub〉12〈/sub〉GeO〈sub〉20〈/sub〉 and γ-Bi〈sub〉2〈/sub〉MoO〈sub〉6〈/sub〉, but also the unique 〈em〉Z〈/em〉-scheme system which can effectively promote the separation of photogenerated electron-hole pairs and sufficiently utilize the photogenerated carriers for generating more active radicals. In addition, based on the active species trapping experiments and electron spin resonance (ESR) spin-trap technique, the photocatalytic mechanism over the 〈em〉Z〈/em〉-scheme γ-Bi〈sub〉2〈/sub〉MoO〈sub〉6〈/sub〉/Bi〈sub〉12〈/sub〉GeO〈sub〉20〈/sub〉 heterostructure is discussed in detail. The research may provide theoretical basis and significant guiding for future development of fabricating other 〈em〉Z〈/em〉-scheme heterostructure with superior photocatalytic performance and high stability.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324651-ga1.jpg" width="329" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Basant Roondhe, Khushbu Patel, Prafulla K. Jha〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Present work aims to develop a two-dimensional graphene-like honeycomb AlC nanostructure as a potential gas sensor to efficiently capture the CO and CO〈sub〉2〈/sub〉 gas molecules for purification of pollutants exhausted from fuel engines. Structural, dynamical, electronic and sensing properties of newly predicted hexagonal AlC monolayer (h-AlC) are investigated through first principles calculations based on density functional theory (DFT). Our studies report metallic nature of h-AlC. The real frequency of phonon modes in phonon dispersion curves (PDC) indicates dynamical stability of the h-AlC structure. The sensing ability of the h-AlC increases through the substitution of nearby radii elements B, N, P, and Si without any structural distortion in h-AlC. All calculations of adsorption energy, electronic density of states (DOS), charge transfer mechanism and work function analysis are performed with dispersion corrected density functional theory. The P substituted AlC (P-AlC) shows a strong binding with CO and CO〈sub〉2〈/sub〉 molecules with an adsorption energy of −1.069 eV and −0.848 eV respectively. The work function calculation and shorter recovery time (in Peco sec.) of the monolayer confirm its novelty as a sensor.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉Birth of new scraper in the two-dimensional family, aluminium carbide for capturing CO and CO〈sub〉2〈/sub〉 at trace level.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324821-ga1.jpg" width="316" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Kai Zhu, Yuanming Chen, Chaoying Ma, Wei He, Chong Wang, Shouxu Wang, Guoyun Zhou, Zhi Wang, Yaqing Liu, Yunzhong Huang, Weihua Zhang, Yukai Sun〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The micron-size anisotropic growth of electroless nickel‑phosphorus plating was realized on the fine sliver lines with the width of ≤15 μm. Growth of nickel‑phosphorus alloy occurred preferentially in the width direction at a growth rate approximately twice than that in the thickness direction during electroless plating in a bath with periodical positive and negative rotation. The growth rate in the width direction reaches 15–18 μm in 30 min. The dominant nickel‑phosphorus growth in the width direction is attributed to the enhancement of mass transfer rate for solution at the edge of silver lines or nickel‑phosphorus layer, as a result of the better wettability of ceramic than Pd-activated silver and nickel‑phosphorus layer. The suppression of lead acetate at the layer edge is enhanced by nonlinear diffusion instead of wettability difference. A possible mechanism for the formation of nickel‑phosphorus layer morphology as functions of mass transfer and lead distribution was proposed to explain the growth behavior of anisotropic electroless nickel‑phosphorus plating. Furthermore, this anisotropic electroless nickel‑phosphorus plating process was employed to form a novel L-shape terminal electrode structure of chip inductor.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324304-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 496〈/p〉 〈p〉Author(s): Hualun Li, Ye Li〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A novel Ag-doped silicon-based nanosphere (MSA) adsorbent is successfully prepared via a layer-by-layer assembly method for efficient capture of radioactive iodide from aqueous solutions. The Ag〈sub〉2〈/sub〉O nanoclusters was uniformly embedded into the flexible MPs-SiO〈sub〉2〈/sub〉 to construct a heterogeneous silver platform on the surface of silicon-based materials, resulting in massive generation of high specific binding sites, which were regarded as the strong binding center of radioiodine anion. And incorporation of SiO〈sub〉2〈/sub〉 into the intermediate layer can improve chemical and thermal stability of MSA and protects the core from corrosion of electrochemical reactions. Predominant MSA adsorbent exhibited an excellent adsorption capacity of I〈sup〉−〈/sup〉 (236.98 mg/g) which was attributed to the irreversible reaction process of AgI solid-liquid interface precipitation between I〈sup〉−〈/sup〉 and the Ag〈sub〉2〈/sub〉O nanoclusters of interfacial site-directed growth on MPs-SiO〈sub〉2〈/sub〉. The MSA adsorbent also exhibited a rapid adsorption process and was consistent with the pseudo-second-order kinetics model. Furthermore, the selectivity of the MSA adsorbent for I〈sup〉−〈/sup〉 was found to be fairly desirable by the adsorption tests under the harsh conditions. These results indicate that superior MSA can find practical applications in the fields of the radionuclides removal and recovery.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219325048-ga1.jpg" width="440" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): Barnali Bhattacharya, Debolina Paul, Utpal Sarkar〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This study aims to engineer electronic and optical properties of newly designed ‘graphyne with XN at hexagonal ring’ (labeled as XN-ynes, where X = B, Al, Ga). Except BN-yne, all XN-ynes are indirect band gap semiconductors, having larger gap than pristine graphyne. The Raman and IR spectra of XN-yne exhibit quite distinct feature with respect to pristine graphyne and strong Raman and IR line shows regular dependence on group IIIA element, thus may help to detect them during synthesis. The optical band gap calculated by G〈sub〉0〈/sub〉W〈sub〉0〈/sub〉 and Bethe-Salpeter equation (BSE) approach indicates the possibility of their usage as UV light absorber. The optical band gap is arises from π to π* transition. Not only optical band gap but also the strong absorption peak lies in UV region of electromagnetic spectra that also suggesting their possible use as UV light absorber. This study proposes an important initial step towards the applications of these newly designed XN-ynes.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324092-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): Arun Kumar Rai, Ramakanta Biswal, Ram Kishor Gupta, Sanjay Kumar Rai, Rashmi Singh, Uttam Kumar Goutam, K. Ranganathan, P. Ganesh, Rakesh Kaul, Kushvinder Singh Bindra〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this paper, effect of laser shock peening (LSP) on high temperature oxidation behavior of P91 steel has been studied. P91 samples were subjected to single and triple LSP treatments at a constant laser power density of 3.9 GW.cm〈sup〉−2〈/sup〉. Single and triple LSP treatment led to the formation of ultrafine subgrains of sizes ~300 ± 30 and ~105 ± 10 nm respectively at near surface comparing to unpeened P91 sample (~1200 ± 120 nm). Further, unpeened and LSP treated samples were oxidized at temperatures of 600, 650 and 700 °C for time 5 to 200 h in air. Compare to unpeened sample, single and triple peened samples exhibited two and five fold reduction in weight gain after 200 h of oxidation at highest test temperature (700 °C). Improvement of oxidation resistance in LSP treated samples is attributed to the formation of continuous layer of protective oxides such as (Fe,Cr)〈sub〉2〈/sub〉O〈sub〉3〈/sub〉, Cr〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 and MnCr〈sub〉2〈/sub〉O〈sub〉4〈/sub〉 due to enhanced diffusivity of Cr and Mn from bulk during early stage of oxidation. The enhanced diffusivity Cr and Mn in LSP treated samples have been further supported by reduction in apparent activation energy of oxidation, which is evaluated by modelling the time-temperature dependence of weight gain data in purview of kinetics theory.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219324080-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): Dan Zhang, Xiufang Cui, Guo Jin, Xiangru Feng, Bingwen Lu, Qiliang Song, Chenfeng Yuan〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Graphene (Gr) has been regarded as the promising reinforcement for metal matrix composite coatings. However, it is hard to mix nano-scale Gr with micron-scale metal powders effectively at present, restricting the extensive application of Gr in engineering field. Therefore, this work proposed a new two-step method to in-situ synthesize multilayer Gr on the surface of Ni60 powders by combining ultrasonic and wet milling. Under protective atmosphere, Ni60 + Gr coatings were fabricated using laser cladding technique. In-situ synthesized multilayer Gr were successfully incorporated into Ni60 coatings, but part of them were transformed into the fullerene-like structures. In addition, a new matrix phase of Ni-Cr-Fe with bcc structure was generated in Ni60 + Gr coatings owing to the super adsorption effect of Gr on Ni, Cr and Fe atoms. The second phases such as chromium carbides in Ni60 + Gr coatings were refined and distributed more uniformly compared with that of Ni60 coatings. Furthermore, Ni60 + Gr coatings showed excellent tribological performance than that of Ni60 coatings, which was attributed to the synergistic effect between the lubrication of Gr or fullerene-like structures and the superior dispersion strengthening of the second phases.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): Rajeswari Ponnusamy, Rajiu Venkatesan, Abhijeet Gangan, Rutuparna Samal, Brahmananda Chakraborty, Dattatray J. Late, Chandra Sekhar Rout〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Catechol, an essential industrial feedstock is one of the major environmental pollutant which causes several health issues including skin irritation, eye damage and genetic defects. In this work, we have investigated the catechol sensing performance of ZnO/RGO composites for its quantitative detection. ZnO/RGO composite showed superior electron transfer kinetics, sensitivity (162.04 μA mM cm〈sup〉−2〈/sup〉) and lower detection limit (47 nM) than that of bare ZnO nanoparticles. Further, the change in the zeta potential towards the lower negative demonstrated the strong electrostatic interaction between ZnO-RGO and catechol where it is converted as 1, 2 Benzoquinone through redox reactions. By using state of the art of Density Functional Theory simulations, we have demonstrated the interaction of catechol molecule on various ZnO clusters and RGO supported ZnO clusters. The strong bonding between p orbital of O atom of catechol and d orbital of Zn atom and its charge transfer facilitate the oxidation of catechol molecule. In the presence of RGO, the binding energy of catechol and charge transfer increases which qualitatively infer that RGO/ZnO exhibits higher sensitivity compared to bare ZnO and in consistency with the experimental observations.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219323852-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): R. Murugesan, M. Gopal, G. Murali〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Carbon Nanotubes (CNTs) are used as ideal reinforcement due to their high strength, high elastic modulus and high aspect ratio in fabrication of metal matrix composites. But the uniform distribution of the nano reinforcements (CNTs) in the matrix is very difficult to achieve due to their high aspect ratio and Van der Waals force among them. Due to this effect the expected properties may not be achieved in the resulting composites. To overcome this issue and improve the distribution of CNTs in the matrix the Molecular Level Mixing (MLM) of CNTs with Cu/Ni followed by Mechanical Alloying (MA) can be used effectively with functionalized CNTs.〈/p〉 〈p〉Micron sized Cu-CNTs and Ni-CNTs composite powders were prepared by MLM. Then the composite powder was mixed with Al matrix powder by MA. The composite powder obtained after MA were consolidated using spark plasma sintering (SPS). The Microstructure of the sintered Al/Cu-CNT and Al/Ni-CNT composites was characterized by Optical microscope, Scanning Electron Microscope (SEM). Also hardness, wear and thermal expansion were measured. The results show that mechanical properties of the Cu and Ni coated CNTs reinforced composites are enhanced when compared with Al/CNT composite and pure Al sample. This is due to uniform distribution of CNTs in the Al matrix and strong interfacial bonding.〈/p〉 〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219323360-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): Anteneh Marelign Beyene, Jong Hyuk Yun, Syed Abdul Ahad, Brindha Moorthy, Do Kyung Kim〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Li‑sulfur batteries are expected to transform electrochemical energy storage technology by taking it to the next level, as it holds the possibility to obtain a higher energy density levels than state-of-the-art Li-ion batteries. The poor electrical conductivity of sulfur and the high diffusivity of the intermediate lithium polysulfides create various problems, which limit the utilization of the full potential of these batteries. Polar conductive sulfur hosts such as titanium nitride (TiN) make it possible to realize remarkable improvements in active material utilization and capacity retention outcomes over long-term cycling. It has not been possible to use these polar, conductive, ceramic materials for higher active material loading (〉2 mg cm〈sup〉−〈/sup〉〈sup〉2〈/sup〉) due to their low flexibility compared to carbonaceous materials. Here, we demonstrate the possibility of designing a three-dimensional free-standing electrode using polycrystalline 1-D TiN for a relatively high sulfur loading of 2.5 mg cm〈sup〉−〈/sup〉〈sup〉2〈/sup〉. The electrochemical performance of this 1-D TiN-based electrode is compared to that of an electrode based on 1-D TiO〈sub〉2〈/sub〉 (the starting material for TiN synthesis). The results demonstrate the catalytic effect of TiN by virtue of its endowed conductivity, leading to remarkable capacity retention and better active material utilization at high C-rates compared to a TiO〈sub〉2〈/sub〉-based electrode.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219323384-ga1.jpg" width="440" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 494〈/p〉 〈p〉Author(s): Yue Zhang, Li Liu, Sidra Jamil, Jianjun Xie, Wen Liu, Jing Xia, Su Nie, Xianyou Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Na〈sub〉0.44〈/sub〉MnO〈sub〉2〈/sub〉 is expected to be a cathode material with an excellent electrochemical performance for sodium ion batteries due to its unique 3-dimensional (3D) S-type tunnel structure. However, the high cut-off working potential of Na〈sub〉0.44〈/sub〉MnO〈sub〉2〈/sub〉 is usually restricted below 4.0 V (vs. Na/Na〈sup〉+〈/sup〉) to inhibit fast capacity fading. Although pristine Na〈sub〉0.44〈/sub〉MnO〈sub〉2〈/sub〉 submicron rods deliver a high initial discharge capacity of 108.0 mAh g〈sup〉−1〈/sup〉 at 0.4C (1C = 121 mAh g〈sup〉−1〈/sup〉) in the wide voltage range of 2.0–4.5 V however the discharge capacity reduces to 80.5 mAh g〈sup〉−1〈/sup〉 after 200 cycles. For improving the electrochemical properties under high voltage, Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 coated Na〈sub〉0.44〈/sub〉MnO〈sub〉2〈/sub〉 is prepared by a wet-coating process and the coating amount is optimized. The as-prepared 2 wt% Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉-coated Na〈sub〉0.44〈/sub〉MnO〈sub〉2〈/sub〉 submicron rods possess the best electrochemical performance between 2.0 V–4.5 V, which deliver an initial discharge capacity of 109.8 mAh g〈sup〉−1〈/sup〉 at 0.4C and maintain capacity retention of 93.2% after 200 cycles. Moreover, in long-term cycle performance at high current density (4C) between 2.0 and 4.5 V, 2 wt% Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉-coated Na〈sub〉0.44〈/sub〉MnO〈sub〉2〈/sub〉 can retain 79% capacity after 500 cycles. The mechanism of elevated electrochemical performance for Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉-coated Na〈sub〉0.44〈/sub〉MnO〈sub〉2〈/sub〉 submicron rods in high voltage is systematically investigated.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219322901-ga1.jpg" width="349" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): Qianwu Wang, Yang Li, Zelin Shen, Xinlei Liu, Chuanjia Jiang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Hierarchical porous materials have a wide application prospect in heterogeneous catalysis because they can provide plentiful surface active sites and well-developed mass transfer channels while being easily separable, as compared with their nanosized counterparts. In this study, three-dimensional hausmannite (Mn〈sub〉3〈/sub〉O〈sub〉4〈/sub〉) hierarchical micron-sized materials (Mn〈sub〉3〈/sub〉O〈sub〉4〈/sub〉-H) were synthesized by a simple room-temperature aqueous solution route. The catalytic performance was evaluated by activation of peroxymonosulfate (PMS) to oxidize phenol, a model organic pollutant, in aqueous solution. The Mn〈sub〉3〈/sub〉O〈sub〉4〈/sub〉-H showed a higher efficiency in activating PMS for phenol oxidation than two Mn〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 nanomaterials, i.e., nanoparticles and nanorods, attributed to the higher specific surface area and more surface reactive sites arising from the hierarchical structure. The Mn〈sub〉3〈/sub〉O〈sub〉4〈/sub〉-H also showed high catalytic stability, with low Mn leaching during phenol degradation tests. Phenol degradation reaction kinetics followed the pseudo-first-order rate laws, and the reaction was accelerated at higher temperature. In addition, the effects of important operation parameters such as catalyst loading and PMS concentration on catalytic performance of Mn〈sub〉3〈/sub〉O〈sub〉4〈/sub〉-H were evaluated. The present research provides a facile approach for synthesis of green and effective catalytic materials to be used in PMS-based advanced oxidation processes for environmental remediation.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219323657-ga1.jpg" width="301" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): Naveed A. Khan, Behnam Akhavan, Haoruo Zhou, Li Chang, Yu Wang, Lixian Sun, Marcela M. Bilek, Zongwen Liu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉High entropy alloys in the form of thin films have been of growing interest in the past few years due to their unique properties such as high corrosion resistance, superior hardness, and high electrical resistivity. We used RF magnetron sputtering to fabricate high entropy alloy thin films of AlCoCrCu〈sub〉0.5〈/sub〉FeNi. To tune the microstructure and mechanical properties of the films, three different working pressures of 5, 10, and 15 mTorr were utilized. The films grown at 10 mTorr had the largest grain size with highest surface roughness measured by scanning electron microscope (SEM) and atomic force microscope (AFM), respectively. Energy dispersive spectroscopy (EDS) results show that films grown at lower pressure (5 mTorr) are X-ray amorphous and have significantly higher concentration of aluminium (over 35%) due to the reduced scattering of Al atoms on route to the substrate. The films deposited at 10 mTorr are composed of a mixture of FCC and BCC crystal structures as determined using X-ray diffraction (XRD); have protective surface oxide layers of Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 and Cr〈sub〉2〈/sub〉O〈sub〉3〈/sub〉, as observed by X-ray photoelectron spectroscopy (XPS); and have high electrical resistivity (over 4500 μΩ-cm) and high hardness (over 13 GPa). This work shows that the deposition pressure is a critical growth parameter that can be used to tune the microstructure and the properties of sputter deposited HEA thin films with potential applications as protective and hard coatings for aerospace and energy applications.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219323578-ga1.jpg" width="279" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): Tianhui Jiang, Zhuan Li, Peng Xiao, Yan-meng Cheng, Zeyan Liu, Shu Yu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Substrates surface containing with polar components has a great influence on the synthesis of sol-gel derived calcium phosphate coatings. This paper reports the synthesis of calcium phosphates coatings on native and pre-oxidated C/C-SiC (SiC-coated carbon/carbon) substrates, and compares their differences in composition, structure and in vitro bioactivity. C/C-SiC composites were prepared by CVD (chemical vapor deposition) at 1100 °C for 25 h and modified with aqua regia (HCl/HNO〈sub〉3〈/sub〉) for 2 h. Then the coatings were manufactured by sol-gel combined with dip-coating technique. It is shown that the pre-oxidation promotes the formation of dispersed beta-tricalcium phosphate (β-TCP) particles, and the conversion of calcium phosphates coatings from hydroxyapatite (HA) to BCP (HA/β-TCP). The formed β-TCP is composed of hexagonal and orthorhombic systems, and HA is mainly hexagonal crystal. Additionally, the BCP coating on C/C-SiC exhibits better bioactivity compared to pure HA coating during immersion in simulated body fluid (SBF), which is result from the negatively functional groups 〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉OH and 〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉COOH formed on pre-oxidated surface. These groups disturb the stability of sol via electrostatic interaction and induce the nucleation of β-TCP. Hence, the BCP coating with preferential dissolution of β-TCP phases reveals better apatite formation capability.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): Pengfei Wang, Peidong Xue, Cheng Chen, Dongfeng Diao〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Structural and tribological performances of graphene nanocrystallited carbon nitride (GNCN) films were investigated. The GNCN films were prepared in a multifunctional electron cyclotron resonance plasma system with the variation of the microwave power from 300 to 700 W. An increase in the growth rate and a decrease in the nitrogen atomic concentration were clearly observed with increasing microwave power. Whereas, the residual stress, surface roughness (Ra), and nano-scratch depth of the GNCN films were independent of the microwave power. Raman and XPS characterizations of the GNCN films indicated a gradual increase in 〈em〉sp〈/em〉〈sup〉2〈/sup〉 carbon bonding structures as well as the size of the graphene nanocrystallite. When rubbing against the Si〈sub〉3〈/sub〉N〈sub〉4〈/sub〉 balls, low friction coefficients of approximately 0.05 were achieved in nitrogen gas atmosphere. Low friction was attributed to the formation of a uniform tribofilm on the wear scar of the worn Si〈sub〉3〈/sub〉N〈sub〉4〈/sub〉 ball surface. TEM-EELS analysis of the transfer film evidenced the formation of graphene nanocrystallites and the loss of nitrogen atoms in the topmost layer. It is strongly argued that the evolution of carbon 〈em〉sp〈/em〉〈sup〉〈em〉2〈/em〉〈/sup〉 structure on the contact interface is favorable for obtaining low friction coefficient of the GNCN films in nitrogen gas environment.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219323888-ga1.jpg" width="492" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): Wen Lei, Haijun Zhang, Dezheng Liu, Liangxu Lin〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Making full use of the high water-holding capability of bacterial cellulose, a highly N/S dual-doped carbon fibers (NSCF) with interconnected three dimensional structure is prepared by an absorption-swelling strategy. Supercapacitor electrode fabricated from this material delivers a high specific capacitance of 202 F g〈sup〉−〈/sup〉〈sup〉1〈/sup〉, which is two times higher than that of the pristine un-doped one at current density of 1.0 A g〈sup〉−〈/sup〉〈sup〉1〈/sup〉. This dual-doped NSCF shows good wettability, fast ion-transportation and desirable electrical conductivity, which are indispensable characters of an electrode material in building the supercapacitor with desired high power performances.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉Three-dimensional nanofibrous NSCFs with a high N/S doping content (6.90 at.% for N and 1.02 at.% for S) were obtained via an absorption-swelling strategy and subsequent heat treatment.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219323694-ga1.jpg" width="213" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): Fatemeh Poshtiban, Ghasem Bahlakeh, Bahram Ramezanzadeh〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In the present integrated experimental/theoretical work, the synergistic inhibition effects of aminotris methylene phosphonic acid (ATMP) and Zn ions for steel corrosion mitigation in NaCl solution were examined. The inhibition property of ATMP:Zn mixture was evaluated by electrochemical approaches including potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS). In addition, the chelation between ATMP‑zinc ions and/or iron cations was investigated applying various morphological approaches. The ATMP and ATMP-Zn complex chemical structures were identified via UV–Vis and FT-IR spectra. According to EIS outcomes, the excellent inhibition efficiency of about 99% was achieved within 72 h steel subjection to 3.5% NaCl media containing 200:600 ppm ATMP:Zn mixture. The PDP plots disclosed that the complex inhibitors mainly retarded the steel corrosion cathodically. Furthermore, FE-SEM and AFM microstructures analyses clarified the emergence of a high-coverage ATMP:Zn complex inhibitive layer over metallic adsorbent, evidencing significant corrosion mitigation. The detailed results elucidated from EDS and XPS spectra ensured the successive chemical bonding of ATMP molecules with zinc and/or iron ions. Alongside experiments, fundamental theoretical studies at detailed microscopic levels (i.e., atomic and electronic) were conducted using molecular simulations and quantum mechanics (QM). Monte Carlo (MC) combined with molecular dynamics (MD) was applied for assessing the organic-inorganic inhibitor adsorption features. Additionally, electronic-structure QM calculation on the basis of density functional theory (DFT) was adopted so as to fundamentally analyze the reactive sites determining the inhibitor adsorption. The outcomes elucidated by MC/MD tools ensured the surface adsorption propensity of hybrid inhibitors. The DFT based observations proposed that the inhibitors adsorption likely occurs at interface through donor-acceptor interactions.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219323797-ga1.jpg" width="301" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): Benyuan Ma, Yang Peng, Dongwei Ma, Zhao Deng, Zhansheng Lu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Nitrogen reduction reaction (NRR) for ammonia synthesis under mild conditions is promising but remains big challenge. Here, by the DFT method, we investigate the electrocatalytic NRR of boron-doped InSe (B-InSe) monolayer, which is expected to benefit from both the empty orbital of B ion and the favorable carrier mobility of InSe substrate. DFT calculations reveal that this marriage endows B-InSe with excellent electrocatalytic activity to reduce N〈sub〉2〈/sub〉 into NH〈sub〉3〈/sub〉 under ambient conditions. B-InSe attracts N〈sub〉2〈/sub〉 and H strongly around B catalytic center, while presents unstable adsorptions on other surface sites, hence the competing hydrogen evolution reaction (HER) can be well avoided. As N〈sub〉2〈/sub〉 is adsorbed, B ion exchanges electrons with N〈sub〉2〈/sub〉 by the acceptance-donation pattern. Interestingly, the three In ions which nearest to B ion can offer assistance to denote electrons to N〈sub〉2〈/sub〉. In the following hydrogenation steps, this B〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉In〈sub〉3〈/sub〉 moiety plays role of reaction generator, while InSe substrate acts as electron reservoir. The NRR is performed along favorite distal pathway with low overpotential of 0.50 V, and the hydrogenation can be proceeded spontaneously except the steps of *N-NH〈sub〉2〈/sub〉 and *NH〈sub〉3〈/sub〉 show free energy uphill. These results indicate that B-InSe monolayer offers a new opportunity for efficient electrocatalyst for NRR.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S016943321932241X-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): Jikai Xu, Chenxi Wang, Runbo Zhang, Ji Cheng, Ge Li, Junshan Xiang, Yanhong Tian〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The combination of lithium niobate (LiNbO〈sub〉3〈/sub〉) and glass without an intermediate layer is an essential component of micro/nanofluidics and optical waveguides. Direct bonding is a popular method for joining homo/heterogeneous materials into a single composite. However, direct bonding of LiNbO〈sub〉3〈/sub〉 and glass is extremely difficult due to the chemical inertness of LiNbO〈sub〉3〈/sub〉 and the large mismatch of the coefficients of thermal expansion of these materials. In this work, we realized direct bonding of LiNbO〈sub〉3〈/sub〉 and glass via VUV/O〈sub〉3〈/sub〉 activation at 150 °C. Focused ion beam microfabrication tests and observation by scanning electron microscopy and transmission electron microscopy confirmed the strong LiNbO〈sub〉3〈/sub〉/glass bonding interfaces. The excellent transmittance and piezoelectric properties of the direct bonded pairs and the single-crystal orientation of the LiNbO〈sub〉3〈/sub〉 close to the glass demonstrated that the VUV/O〈sub〉3〈/sub〉 activated direct bonding method was suitable for the fabrication of high-performance surface acoustic wave (SAW)-actuated LiNbO〈sub〉3〈/sub〉-based devices. Additionally, we investigated the bonding mechanism through water contact angles, atomic force microscopy, Raman spectroscopy, FTIR spectroscopy, and adhesion measurements.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉Direct bonding of LiNbO〈sub〉3〈/sub〉 and glass was realized via the VUV/O〈sub〉3〈/sub〉 activation at 150 °C.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219323736-ga1.jpg" width="272" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 494〈/p〉 〈p〉Author(s): Ya.V. Zaulychnyy, V.M. Gun'ko, Y.V. Yavorskyi, I.M. Gasyuk, N. Wanderka, O.I. Dudka〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Ultra-soft X-ray emission spectroscopy was used to study the distribution of Op-, Sisd- and Alsd- valence electrons in (SiO〈sub〉2〈/sub〉)〈sub〉x〈/sub〉(Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉)〈sub〉1-x〈/sub〉 (x = 0.8, x = 0.7) powder mixtures after mechanical treatment. An increase in atomic charges has been measured and can be explained by the transfer of electrons from Si/Al to O atoms in split Opπ-binding states and the formation of the weak long (O〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉O)π bonds between the surface atoms of the contacted powder nanoparticles. Scanning and transmission electron microscopy images show an enhanced agglomeration of the nanoparticles of both SiO〈sub〉2〈/sub〉 and Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 oxides, but no changes in the crystalline parameters have been measured using X-ray diffraction. An increase in charge capacities of lithium ion power sources with 0.8SiO〈sub〉2〈/sub〉–0.2Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 electrode has been observed during cycling. At the same time, a decrease of the charge capacities with the 0.7SiO〈sub〉2〈/sub〉–0.3Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 electrode has been measured. The results are discussed in terms of an increase in the binding energy of electrons in the Op-states, which prevents the recombination and irreversible reactions of lithium with electrode atoms. Otherwise, due to cycling, electron population increase of in non-binding states near the valence band top contributes to the recombination ability of Li〈sup〉+〈/sup〉 ions and leads to a decrease in the charge capacity.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219322421-ga1.jpg" width="257" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): Jiangtao Wang, Jinyao Dong, Yao Xue, Xiaohong Yan, Quan Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Two-dimensional layer materials have been of great interest in the promising application of novel nano-electronics in recent years. In this study, we demonstrated the modification on electronic properties of bilayer MoS〈sub〉2〈/sub〉 field-effect transistor (FET) by low-temperature oxygen plasma treatment with different radio frequency (RF) power. According to the I-V measurement with Cascade semi-automatic probe station, it was observed that the electronic properties of bilayer MoS〈sub〉2〈/sub〉 FET could be improved effectively after low-power oxygen plasma treatment. The analysis of transport properties in MoS〈sub〉2〈/sub〉 revealed the modification mechanism of sulphur (S) vacancies by low-power oxygen plasma. Nevertheless, electronic properties of MoS〈sub〉2〈/sub〉 FET were degenerated after high-power oxygen plasma treatment for the increase of defect in MoS〈sub〉2〈/sub〉, which has been characterized by Raman spectrum and XPS spectrum. Furthermore, it was found that the signal distributions of surface contact potential difference (CPD) and capacitance of MoS〈sub〉2〈/sub〉 mono-crystal samples prepared by chemical vapor deposition (CVD) were heterogeneous, which demonstrates that the edge region of MoS〈sub〉2〈/sub〉 can be interacted by oxygen plasma more easily owing to the defect and active sites. This study will provide a theoretical basis in the research of next-generation high-performance electronic device.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): N.S.K. Gowthaman, P. Arul, Jae-Jin Shim, S. Abraham John〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Hydrogen peroxide (HP) is considered as cytotoxic and its levels in human may be controlled by catabolism and excretion. It plays an important role in renal function regulations and as an antibiotic in urine and the urinary HP level under certain conditions will be a precious biomarker of oxidative stress. Hence, this study aimed to develop a sensitive electrochemical flexible sensor to determine HP in human urine using Au-AgNPs fabricated carbon cloth. Initially, Au-AgNPs were fabricated by electroless deposition which involves immersion of electrode in AgNO〈sub〉3〈/sub〉-ascorbic acid bath for an hour followed by its immersion in HAuCl〈sub〉4〈/sub〉. The deposited AgNPs served as a sacrificial system for Ag-AuNPs growth by galvanic displacement. SEM images exhibited the 30 and 55 nm sized AgNPs and Au-AgNPs, respectively at optimized conditions and their zero valent nature was confirmed by XPS. Further, composition dependent HP reduction was realized at the Au-AgNPs electrode. Amperometric HP determination was achieved in 500 nM-2 mM range with 59 nM (S/N = 3) limit of detection. The present sensor shows superior sensitivity of 3523.14 μA mM〈sup〉−1〈/sup〉 cm〈sup〉−2〈/sup〉 than the reported sensors. Ultimately, the flexible electrochemical sensor fabricated on carbon cloth detects HP in freshly voided human urine and blood serum samples.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉Au-Ag bimetallic nanoparticles were fabricated on carbon cloth by electroless deposition and utilized as an electrochemical sensor for the biomarker of oxidative stress by monitoring H〈sub〉2〈/sub〉O〈sub〉2〈/sub〉 level in human urine samples.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219323475-ga1.jpg" width="344" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): G.D. Takalkar, R.R. Bhosale〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This investigation describes the application of the sol-gel synthesized Co〈sub〉x〈/sub〉Fe〈sub〉3−x〈/sub〉O〈sub〉4〈/sub〉 (CF) materials towards the solar thermochemical fuel production. The CF materials were derived by sol-gel method (where x was varied in the range of 0.2 to 1) and the prepared CF materials were further characterized using multiple analytical techniques. The characterization results specify formation of CF nanoparticles with phase pure composition and high SSA. A high temperature thermogravimetric analyzer (TGA) was employed to determine the redox reactivity of the CF materials towards CO〈sub〉2〈/sub〉 splitting reaction. The obtained experimental findings showed that the incorporation of CO〈sup〉+2〈/sup〉 into iron oxide crystal structure was advantageous to accomplish higher CO production rate via CO〈sub〉2〈/sub〉 splitting. The highest amount of CO production was observed in case of CoFe〈sub〉2〈/sub〉O〈sub〉4〈/sub〉 (145.2 μmol/g of CO). It was further realized that the CoFe〈sub〉2〈/sub〉O〈sub〉4〈/sub〉 possess better CO〈sub〉2〈/sub〉 splitting ability in comparison to the Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 and CeO〈sub〉2〈/sub〉.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): N. Nedyalkov, M. Koleva, N. Stankova, R. Nikov, A. Dikovska, L. Aleksandrov, R. Iordanova, G. Atanasova, D. Karashanova, K. Grochowska, G. Sliwinski〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The process of laser radiation-induced formation and decomposition of Ag nanoparticles in glass is studied. Borosilicate glass samples are fabricated by melt quenching method. Silver nitrate is added in the fabrication stage in amount to form final glass samples with compositions of 1, 1.5, 5, and 10 wt% Ag. The fabricated samples are irradiated by laser pulses delivered by Nd:YAG nanosecond laser system at wavelength of 266 nm. It is found that at certain conditions laser radiation can induce coloration of the irradiated zone which is related to formation of silver nanoparticles. Detailed analyses are performed to characterize the formed nanoparticles. The application of a subsequent laser treatment of the glass samples with already formed nanoparticles can result in transparency recovery. The effect is demonstrated at wavelength of 355 nm of the Nd:YAG laser system. The observed formation and decomposition of nanoparticles are discussed on the basis of the calculated laser-induced heating dynamics and molecular dynamics simulation model for the silver atom motion. Diffusion growth and redox reactions are found to be responsible for the observed effects.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219323438-ga1.jpg" width="278" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): Mari Elancheziyan, Sellappan Senthilkumar〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Design and development of electrochemical biosensors with improved selectivity, sensitivity and stability is one of the thrust areas of research in analytical and materials chemistry. In the present work, hemoglobin (Hb) was covalently immobilized on polyamidoamine (PAMAM) dendrimer encapsulated with gold nanoparticles (AuNPs), which was further utilized for the electrochemical detection of hydrogen peroxide (H〈sub〉2〈/sub〉O〈sub〉2〈/sub〉). Third generation PAMAM dendrimers were synthesized and AuNPs were encapsulated within the dendrimer network. Hb was covalently immobilized through glutaraldehyde cross-linking between the free amino groups of Hb and that of the PAMAM dendrimer. Hb/PAMAM-AuNPs was immobilized on a glassy carbon electrode (GCE) and the Hb/PAMAM-AuNPs/GCE modified electrode thus fabricated was characterized with electrochemical impedance spectroscopy and cyclic voltammetry. The Hb/PAMAM-AuNPs/GCE biosensor displayed well resolved redox peaks with anodic peak potential at −0.252 V and cathodic potential at −0.321 V, corresponding to Fe(III)/Fe(II) redox couple of heme active centre. Further, the developed Hb/PAMAM-AuNPs/GCE showed very good electrocatalytic activity for the reduction of H〈sub〉2〈/sub〉O〈sub〉2〈/sub〉 at a potential of −0.35 V. The Hb/PAMAM-AuNPs/GCE biosensor has shown impressive performance towards H〈sub〉2〈/sub〉O〈sub〉2〈/sub〉 determination in the concentration range from 20 μM to 950.22 μM. The sensitivity of the biosensor was calculated to be 35.07 μA μM〈sup〉−1〈/sup〉 cm〈sup〉−2〈/sup〉 with a detection limit of 6.1 μM. Also, the Hb/PAMAM-AuNPs/GCE modified electrode exhibited higher stability and good reproducibility.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219323347-ga1.jpg" width="500" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): Yanting Huang, Wugang Liao〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A facile one-pot hydrothermal method was proposed to fabricate nitrogen-doped carbon quantum dots (N-doped CQDs) on the surface of nitrogen-doped carbon nanotube (N-doped CNTs). The microstructure of the N-doped CQDs/N-doped CNTs hybrid was investigated by using transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Furthermore, their electrocatalytic activity of the N-doped CQDs/N-doped CNTs hybrid in oxygen reduction reaction (ORR) was systematically evaluated and it was found that the N-doped CQDs/N CNTs hybrid deposited as such exhibits a high performance for ORR in terms of a low onset potential of −0.03 V vs. Ag/AgCl, a high limiting diffusion current density of ~5.5 mA cm〈sup〉−2〈/sup〉, and a one-step 4e ORR process, holding great potential for future metal-free catalysts.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): Chang Cheng, Xunchang Wang, Feng Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Two analogous positional polymers P16PySO and P27PySO have been synthesized 〈em〉via〈/em〉 the copolymerization from dibenzothiophene-S,S-dioxide and pyrene building blocks. The effect of the linking pattern on the molecular packing, photophysical and photocatalytic properties of the two isomers was investigated. It was interestingly found that a minor change at the substitution position of pyrene unit was demonstrated to largely influence the photocatalytic properties of the two isomers. P16PySO exhibited an encouraging average hydrogen evolution rate (HER) of 619.5 μmol h〈sup〉−1〈/sup〉 and the maximum HER of 774 μmol h〈sup〉−1〈/sup〉, much higher than that of 2,7-counterpart with a moderate rate of 282 μmol h〈sup〉−1〈/sup〉. The increased photocatalytic activity of P16PySO is mainly ascribed to its more ordered molecular packing, broader absorption region, better wettability, and higher photo-generated charge mobilities. Moreover, the optimum HER was increased from 774 to 1013 μmol h〈sup〉−1〈/sup〉 when the amount of the photocatalyst P16PySO was increased from 50 to 100 mg, which is among the top solar-to‑hydrogen conversion efficiencies reported so far for the polymeric photocatalysts.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219323256-ga1.jpg" width="313" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): Youcai Ding, Yuqi Peng, Shuanghong Chen, Zhaoqian Li, Xianxi Zhang, Polycarpos Falaras, Linhua Hu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉2D nanosheets are attractive for energy conversion and storage because of their scale-dependent physical and chemical properties. However, nanosheets synthesized by liquid-phase method are easy to stack and it is difficult to obtain nanosheets with uniform dispersion and thickness. Here, a new strategy was developed to obtain uniformly dispersed 2D nanosheets. The regular dodecahedron structured ZIF-67 was employed as templates and NH〈sub〉4〈/sub〉F was adopted as competitive units. 2D nanosheets of coordination polymers were induced vertically grow from the surface of ZIF-67, which effectively avoiding the stack of nanosheets. After carbonization, the obtained composites of Co〈sub〉3〈/sub〉O〈sub〉4〈/sub〉@carbon retained their original structure. The composites show excellent characteristics as the electrode of a supercapacitor. The capacitance of the NS-Co〈sub〉3〈/sub〉O〈sub〉4〈/sub〉@PC electrode is 940 F g〈sup〉−1〈/sup〉 at a current density of 1 A g〈sup〉−1〈/sup〉, which is about 7 times than that of composite which derived from ZIF-67 under the same conditions. The most important is that the rate performance and cycling life were also improved as the result of hierarchical porous structure and good structure robustness. The method developed here may open up a novel and innovative approach to manipulate the structure of classical MOFs to obtain 2D nanosheets for a wealth of breakthrough applications.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219322871-ga1.jpg" width="323" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): Umesh P. Suryawanshi, Mahesh P. Suryawanshi, Uma V. Ghorpade, Seung Wook Shin, Jihun Kim, Jin Hyeok Kim〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The rational designing of Earth-abundant, low-cost and efficient oxygen evolution reaction electrocatalysts is prerequisite to develop the alternative sustainable energy sources. In this work, we demonstrate the development of a highly efficient and durable electrocatalyst based on an amorphous Co-Fe-B〈sub〉i〈/sub〉 directly grown on three-dimensional nickel foam via a facile solution approach. Co-Fe-B〈sub〉i〈/sub〉 electrocatalysts on nickel foam exhibits an overpotential of ~307 mV to achieve the geometrical current density of 10 mA cm〈sup〉−2〈/sup〉, a low Tafel slope of ~68.6 mV dec〈sup〉−1〈/sup〉 and outstanding durability for 40 h at a mass loading of 1.2 mg cm〈sup〉−2〈/sup〉, which is superior to those of borate-based electrocatalysts reported in the literature〈sub〉.〈/sub〉 This remarkable preliminary electrocatalytic performance in Co-Fe-B〈sub〉i〈/sub〉 originates from the synergistic influence of unique binder-free ultra-thin nanosheets on the three dimensional porous structure, amorphous nature of multimetal-metalloid complex with highly abundant catalytically active sites and high conductivity of nickel foam. This work holds a great promise in the design and development of highly efficient and durable electrocatalysts at a large-scale based on an amorphous bimetallic borate nanosheets using a facile one-step solution process.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉An efficient and durable amorphous cobalt-iron-borate (Co-Fe-B〈sub〉i〈/sub〉) electrocatalyst is fabricated directly on 3D nickel foam via a simple solution approach.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219322408-ga1.jpg" width="308" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 30 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 495〈/p〉 〈p〉Author(s): Zhibin Zhang, Zeyu Zhao, Zhaozhu Zheng, Shuai Liu, Senxian Mao, Xunxun Li, Yushuang Chen, Qingshan Mao, Lu Wang, Fujun Wang, Xiaoqin Wang, Zhijuan Pan, Gang Li〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We demonstrate low-temperature nitrogen plasma (LTNP) and silk fibroin/chitosan microspheres (SFCM) for surface modification and functional treatment of polyethylene terephthalate (PET) fabrics to improve their antibacterial and antistatic properties. First, PET warp-knitting fabrics were treated by LTNP equipment. Then, the LTNP-treated fabrics were treated by SFCM solution. The surface properties of the PET fabrics, such as morphology, chemical composition, secondary structure, moisture regain, antistatic property, and breathability were analyzed using scanning electron microscopy, photoelectron spectroscopy, X-ray photoelectron spectrometer, Fourier transform infrared spectrometer, electrostatic charge decay tester, and automatic air permeability tester. The antibacterial properties of the PET fabrics were measured against. The results showed that the PET fabrics surface was roughened and nitrogen-containing groups were generated after LTNP treatment. Compared to SFCM-treated PET fabrics, the antistatic and hygroscopic properties of the LTNP-SFCM-treated PET fabrics have been significantly improved. The results also revealed that the LTNP-SFCM-treated PET fabrics had excellent antibacterial effects against 〈em〉Staphylococcus aureus〈/em〉 (95.2 ± 1.2%) and 〈em〉Escherichia coli〈/em〉 (92.1 ± 2.7%), and after washing ten times, the LTNP-SFCM-treated PET fabrics still had a strong antibacterial effect (73.1 ± 1.6%). Our approach can find potential applications for the development of functional textiles with improved antistatic and antibacterial performance.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 494〈/p〉 〈p〉Author(s): Subramani Surendran, Sathyanarayanan Shanmugapriya, Harivignesh Ramasamy, Gnanaprakasam Janani, Dharmalingam Kalpana, Yun Sung Lee, Uk Sim, Ramakrishnan Kalai Selvan〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The development of sustainable energy conversion and storage systems is on demand to ease the energy needs and restrict environmental pollution. Here, we account a unique multifunctional flake-like CoS deposited over the flexible carbon cloth (CoS@CC) by a facile hydrothermal technique. The single-phase hexagonal structured CoS@CC with high crystallinity was identified through the XRD analysis. The morphological feature portrays the uniform distribution of flake-like CoS over carbon cloth. The electrocatalytic properties of the prepared flake-like CoS (CoS@CC) suggests improved electroactivity of requiring minimal overpotentials of 280 mV (OER) and 264 mV (HER) to accomplish a pre-eminent current density of 20 mA cm〈sup〉−2〈/sup〉. In addition, a lab-scale water splitting system was projected to achieve a current density of 10 mA cm〈sup〉−2〈/sup〉 with a low cell voltage of 1.65 V. In view to driving the fabricated water splitting system, a flexible (CoS@CC||rGO) supercapattery was fabricated to deliver an improved specific energy of 38 Wh kg〈sup〉−1〈/sup〉 at a superior specific power of 533 W kg〈sup〉−1〈/sup〉. Therefore, the prepared CoS@CC electrode with improved flexibility, useful catalytic activity, expressive kinetics, and resilient strength serves as a multifunctional material for prospective energy conversion and storage systems.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219321981-ga1.jpg" width="253" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 494〈/p〉 〈p〉Author(s): Jinhwan Kim, Jae-Hoon Ji, Dong-Jin Shin, Sanghyun Yoon, Young-Ho Ko, Kyung-Ho Cho, Jung-Hyuk Koh〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Piezoelectric materials have excellent piezoelectric and dielectric properties for versatile device applications. However, they have brittle properties, particularly under mechanical impulse force. As a result, there have been many attempts to improve their brittle properties by mixing in elastic materials. Here, for the first time, reduced graphene oxide (rGO) was introduced to the Pb(Mg〈sub〉1/3〈/sub〉Nb〈sub〉2/3〈/sub〉)O〈sub〉3〈/sub〉–PbTiO〈sub〉3〈/sub〉 (PMN-PT) and poly(vinylidene fluoride-trifluoroethylene) P(VDF-TrFE) polymer composite films, and showed the highest value of piezoelectric and energy density for flexible energy generation applications. rGO has conducting properties with 2-dimensional structure. This rGO can also be prepared through easy processing. 2-dimensional structured rGO serves as a floating electrode in PMN-PT/polymer composite flexible films. Therefore, a floating electrode can attract electrons in piezoelectric composite materials so as to enhance the energy generation properties. By introducing the rGO based floating electrodes into the PMN-PT and P(VDF-TrFE) composite, the generated output energy density was increased from 0.70 mJ/cm〈sup〉3〈/sup〉 to 1.2 mJ/cm〈sup〉3〈/sup〉. This the generated output energy density was the recorded outstanding value among the flexible composite films.〈/p〉 〈p〉In this paper, the effects of rGO on the properties of PMN-PT/polymer composites will be investigated and discussed.〈/p〉 〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219319622-ga1.jpg" width="198" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 494〈/p〉 〈p〉Author(s): Yingying Yang, Jian Chen, Yuzhu Ran, Xudong Wang, Hao Huang, Man Yao〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉First-principles calculations were performed to investigate the catalytic activity of Li〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉O〈sub〉2〈/sub〉 batteries based on TiC and X-doped TiC (X = B, N, Al, Si, and P) materials as potential cathode catalysts. Interfacial models of Li〈sub〉x〈/sub〉O〈sub〉2〈/sub〉 (x = 4, 2, and 1) intermediates adsorbed on doped TiC surface were used to simulate the structural evolution during discharging/charging process. The catalytic activity was quantitatively assessed by specific ORR/OER overpotential, and some intrinsic factors affecting the catalytic activity of doped TiC were determined based on the structure-activity relationships established. The catalytic activity of doped TiC can be divided into two groups, wherein B-, N-, and P-doped TiC have better catalysis than Al- and Si-doped TiC. Among them, B-doped TiC displays the lowest ORR overpotential, suggesting that B-doped TiC has the best catalytic activity of ORR. The stronger (Li〈sub〉2〈/sub〉O)〈sub〉2〈/sub〉/Li〈sub〉2〈/sub〉O〈sub〉2〈/sub〉/LiO〈sub〉2〈/sub〉 adsorption energy induces lower ORR and OER overpotentials. The stronger Li〈sup〉+〈/sup〉 desorption energy attracts lower ORR overpotential, while the weaker O〈sub〉2〈/sub〉 desorption energy induces lower OER overpotential. Consequently, adsorption energy of (Li〈sub〉2〈/sub〉O)〈sub〉2〈/sub〉/Li〈sub〉2〈/sub〉O〈sub〉2〈/sub〉/LiO〈sub〉2〈/sub〉 and desorption energy of Li〈sup〉+〈/sup〉/O〈sub〉2〈/sub〉 are useful factors for characterizing the catalytic activity. These findings contribute to understand the doping effect on catalysis and provide insights into the screening and design of novel catalyst in Li〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉O〈sub〉2〈/sub〉 batteries.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 494〈/p〉 〈p〉Author(s): Zhelun Li, Zhilin Xia〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In the present paper, we have prepared a multi-layer grating on a layer of gold film. The gratings laser damage threshold and damage morphologies have been tested using an 800 nm wavelength, 450 ps laser pulse. The gratings laser damage threshold is 0.95 J/cm〈sup〉2〈/sup〉. Based on the tested damage characteristics and the calculated temperature field and stress field in gratings, the gratings damage mechanism has been analyzed. In theoretical calculation, the ionization process of dielectric layers in gratings and the distribution as well as evolution of the dielectric absorption coefficient have been considered. It can be concluded that the gratings damage process is thermal ablation action dominated.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 494〈/p〉 〈p〉Author(s): Ying Cheng, Wenzhong Wang, Lizhen Yao, Jun Wang, Yujie Liang, Junli Fu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This study provides insights into the charge transfer and solar light photocatalytic activity induced by the synergistic effect between defect state and plasmon in Au nanoparticle-decorated hierarchical 3D porous ZnO microspheres. Photoluminescence emission shows that the photogenerated electrons of ZnO are efficiently transferred from its defect level to the conduction band (CB) induced through the coupling action of the defect state and plasmon. Compared with the pure ZnO microsphere photocatalysts, the fabricated Au/ZnO microsphere photocatalysts show remarkably enhanced activity for the decomposition of methylene blue dyes under solar-light illumination. Moreover, the photocatalytic performance of the Au/ZnO microspheres was manipulated by tuning the size of the Au nanoparticles (NPs). When decorated with 10 nm Au NPs, the Au/ZnO microsphere photocatalyst achieves a rate constant of 0.09846 min〈sup〉−〈/sup〉〈sup〉1〈/sup〉, 26 and 8.5 times higher than those of the pure ZnO microsphere photocatalysts (0.00378 min〈sup〉−〈/sup〉〈sup〉1〈/sup〉) and the Au/ZnO microsphere photocatalysts decorated with 30 nm Au NPs (0.01154 min〈sup〉−1〈/sup〉), respectively.. The enhanced photocatalytic performance of the Au/ZnO microsphere photocatalysts is ascribed to the defect state-plasmon coupling-induced efficient transfer of photogenerated electrons from the defect level to the CB of ZnO. This work enhances the understanding of the defect state-plasmon coupling-induced enhanced photocatalytic activity in metal/semiconductor heterostructure photocatalysts.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉Insights into charge transfer and solar light photocatalytic activity induced by the synergistic effect of defect state and plasmon in Au nanoparticle-decorated hierarchical 3D porous ZnO microspheres.〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169433219323037-ga1.jpg" width="397" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Applied Surface Science, Volume 494〈/p〉 〈p〉Author(s): P. Maheswari, S. Ponnusamy, S. Harish, C. Muthamizhchelvan, M.R. Ganesh, Y. Hayakawa〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉TiO〈sub〉2〈/sub〉 nanoparticles (NPs) are capable of inhibiting the growth of bacterial strains and are responsible for causing damages to the cancer cells. Pure TiO〈sub〉2〈/sub〉, Aqua Rosa-modified TiO〈sub〉2〈/sub〉 and protein powder-modified TiO〈sub〉2〈/sub〉 NPs are synthesized using hydrothermal method. The particle size is found to be 7.5 nm for pure, 6.5 nm for protein-modified and 5.5 nm for Aqua Rosa-modified TiO〈sub〉2〈/sub〉 NPs using TEM analysis. UV spectra shows that the absorption peaks of the modified samples are blue shifted with respect to pure TiO〈sub〉2〈/sub〉 nanoparticles. The surface-modified nanoparticles show maximum growth inhibition against the pathogenic organisms. The research experiments exhibited highest anti-cancer activities for the surface modified TiO〈sub〉2〈/sub〉 NPs.〈/p〉〈/div〉 〈/div〉