ALBERT

Description: 〈p〉Publication date: 5 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 562〈/p〉 〈p〉Author(s): Parisa Moazzam, Giorgio Luciano, Amir Razmjou, Ehsan Akbari, Pavel G. Ul’yanov, Soumitro Mahanty〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The degree of available energy on a surface determines how a surface interacts with its surrounding environment such as corrosion. Current approaches to protection of Aluminum surfaces from corrosion mainly focus on adding an organic or inorganic layer to either act as a barrier from oxidant or scarifying to inhibit the corrosion. Altering the surface energy of Al on a molecular level is another alternative approach to efficiently modify the Al surface without the need for another thick expensive protective or scarifying materials. Herein, an attempt was made to understand how a molecular scale energy alteration improves the anticorrosion behavior of an aluminum surface. Two different surface engineering alteration strategies have been discussed; termed ALOSH and ALTSH modification. A variety of analytical instruments, i.e., FTIR, EDAX, XPS, SEM, AFM, WCA, and SFE measurement were used to systematically characterize the samples. Electrochemical impedance spectroscopy revealed that there are different resistances after the surface modifications. The trapping air resistance appeared in ALTSH is approximately 2.4 and 36 times higher than that of ALOSH and bare samples, respectively. The potentiostat analysis results showed that the mili inch per year value of coating for ALTSH was 0.012 while that of ALOSH was 0.507. It was also found that the low surface energy alteration without using inert molecules is not enough to render corrosion inhibition property, as it needs to have a protective energy barrier with no or minimal active electrochemical behavior.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718311294-ga1.jpg" width="320" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Sai Huang, Zhihao Wang, Qi Zhu, Xiaofei Shi, Xuejiao Wang, Xiaodong Li, Xudong Sun, Ji-Guang Li〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉RE(OH)〈sub〉2.94〈/sub〉(NO〈sub〉3〈/sub〉)〈sub〉0.06〈/sub〉·〈em〉n〈/em〉H〈sub〉2〈/sub〉O nanosquares were first employed as template to synthesize YVO〈sub〉4〈/sub〉:Ln luminescent crystallites (Ln = Eu, Sm, and Dy) via hydrothermal nanoconversion in the presence of NH〈sub〉4〈/sub〉VO〈sub〉3〈/sub〉. Product properties and the course of phase/morphology evolution were characterized in detail by XRD, SEM, TEM, FT-IR, TG, and optical spectroscopy. It was clearly demonstrated that the nanosquares templated vanadate crystallization, owing to structure similarity, but was accompanied by subsequent dissolution and reprecipitation. The resultant vanadate phosphors, mostly in the form of bundles containing platelike and fibrous crystallites, exhibited strong red emission at ∼618 nm for Eu〈sup〉3+〈/sup〉, orange-red emission at ∼604 nm for Sm〈sup〉3+〈/sup〉 and greenish yellow emission at ∼575 nm for Dy〈sup〉3+〈/sup〉 upon exciting the VO〈sub〉4〈/sub〉〈sup〉3−〈/sup〉 ligand. Dehydration at 500 °C further improved the emission by ∼2.5 times for Eu〈sup〉3+〈/sup〉 and ∼1.5 times for Sm〈sup〉3+〈/sup〉 and Dy〈sup〉3+〈/sup〉. The Eu〈sup〉3+〈/sup〉 (5 at%), Sm〈sup〉3+〈/sup〉 (1 at%) and Dy〈sup〉3+〈/sup〉 (1 at%) activators were analyzed to have quantum yields of ∼48, 9 and 16% and color coordinates of around (0.65, 0.33), (0.60, 0.39) and (0.38, 0.43) for their luminescence, and fluorescence lifetimes of ∼1.52, 1.40 and 0.89 ms for their dominant emissions, respectively. It is also interesting to find out that replacing only 15% of the total OH〈sup〉−〈/sup〉 and NO〈sub〉3〈/sub〉〈sup〉−〈/sup〉 anions in the template by VO〈sub〉4〈/sub〉〈sup〉3−〈/sup〉 produced ∼20 times stronger Eu〈sup〉3+〈/sup〉 luminescence, indicating that VO〈sub〉4〈/sub〉〈sup〉3-〈/sup〉→ Eu〈sup〉3+〈/sup〉 energy transfer is very efficient. The protocol would be extendable to other types of functional rare-earth compounds.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818339719-fx1.jpg" width="245" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Chunmu Guo, Qinghua Tian, Li Yang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Nanostructure of titanium dioxide (TiO〈sub〉2〈/sub〉) has gained extensive attention in anode material field of lithium-ion batteries (LIBs) owing to its outstanding structure stability and improved safety over graphite. Herein, facilely controllable synthesis of interestingly spindle TiO〈sub〉2〈/sub〉 nanograins has been achieved by a one-pot hydrothermal and subsequent calcination approach, it is demonstrated that the grain size has a great effect on the electrochemical lithium storage kinetics of as-synthesized TiO〈sub〉2〈/sub〉 nanograins. As a result, the as-prepared TiO〈sub〉2〈/sub〉-0.05M with much smaller size exhibits greatly improved lithium storage performance, delivering a capacity of 120.5 mAh g〈sup〉−1〈/sup〉 after even 1000 cycles.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Xi Cheng, Shi Wei Xu, You Ming Lu, Shun Han, Pei Jiang Cao, Fang Jia, Yu Xiang Zeng, Xin Ke Liu, Wang Ying Xu, Wen Jun Liu, De Liang Zhu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Zn〈sub〉1-x〈/sub〉Cd〈sub〉x〈/sub〉O films with different Cd contents obtained by controlling the growth oxygen pressure (O〈sub〉p〈/sub〉) were deposited on both c-sapphire (Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉) substrates and p-GaN substrates, by means of the pulsed laser deposition (PLD) method. Photoluminescence (PL) measurement revealed that the variation of O〈sub〉p〈/sub〉 influenced the amount of Cd doping into Zn〈sub〉1-x〈/sub〉Cd〈sub〉x〈/sub〉O films deposited on Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉, leading tunable luminescence from the ultraviolet (UV) to blue emission extended to the green band. Then all the fabricated n-Zn〈sub〉1-x〈/sub〉Cd〈sub〉x〈/sub〉O/p-GaN heterojunction possessed good ohmic contacts and exhibited typical rectifying characteristic of the diode. Indeed, the high luminescence from the ZnCdO layer could be attained by inserting a MgO insulator to the heterojunction interface. The fabrication of tunable n-Zn〈sub〉1-x〈/sub〉Cd〈sub〉x〈/sub〉O/p-GaN heterojunction light-emitting diodes is available which was supported by the results of electroluminescence (EL) experiment.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Dina V. Deyneko, Ivan V. Nikiforov, Bogdan I. Lazoryak, Dmitry A. Spassky, Ivan I. Leonidov, Sergey Yu. Stefanovich, Daria A. Petrova, Sergey M. Aksenov, Peter C. Burns〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Novel red emitting phosphors Ca〈sub〉8〈/sub〉MgSm〈sub〉1–〈em〉х〈/em〉〈/sub〉(PO〈sub〉4〈/sub〉)〈sub〉7〈/sub〉:〈em〉x〈/em〉Eu〈sup〉3+〈/sup〉 with whitlockite-type structure were prepared by a high temperature solid-state reaction in air. Powder X-ray diffraction (PXRD), photoluminescence spectra, and fluorescence decay were used to characterize the structure and luminescence properties. All samples were found to have the expected rhombohedral structure with 〈em〉R〈/em〉〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.gif" overflow="scroll"〉〈mrow〉〈mover accent="true"〉〈mn〉3〈/mn〉〈mo〉¯〈/mo〉〈/mover〉〈/mrow〉〈/math〉〈em〉c〈/em〉 space group. The non-polar space group is also confirmed by a photoluminescence study. This space group allows forbidden transitions for Eu〈sup〉3+〈/sup〉. The presence of only one Shtark component in 〈sup〉5〈/sup〉D〈sub〉0〈/sub〉–〈sup〉7〈/sup〉F〈sub〉0〈/sub〉 confirms the presence of only one non-equivalent site containing Eu〈sup〉3+〈/sup〉 ions. The high intensity of the transition ratio 〈sup〉5〈/sup〉D〈sub〉0〈/sub〉–〈sup〉7〈/sup〉F〈sub〉2〈/sub〉/〈sup〉5〈/sup〉D〈sub〉0〈/sub〉–〈sup〉7〈/sup〉F〈sub〉1〈/sub〉 establishes the strongly disordered environment of the Eu〈sup〉3+〈/sup〉 ions. Thus, 〈em〉M〈/em〉1–〈em〉M〈/em〉3 sites in the host matrix are occupied by Ca〈sup〉2+〈/sup〉, Sm〈sup〉3+〈/sup〉, and Eu〈sup〉3+〈/sup〉 ions, whereas 〈em〉M〈/em〉5 is fully occupied by Mg〈sup〉2+〈/sup〉. The optimal concentration was found with 〈em〉x〈/em〉 = 0.75 in Ca〈sub〉8〈/sub〉MgSm〈sub〉1–〈em〉х〈/em〉〈/sub〉(PO〈sub〉4〈/sub〉)〈sub〉7〈/sub〉:〈em〉x〈/em〉Eu〈sup〉3+〈/sup〉 phosphors. The emitting of Sm〈sup〉3+〈/sup〉 was depressed due to the high intensity of Eu〈sup〉3+〈/sup〉 luminescence; however, the contribution of Sm〈sup〉3+〈/sup〉 is manifested in the energy transfer process and shift of CIE coordinates. Furthermore, the CIE chromaticity coordinate of 〈em〉as-prepared〈/em〉 Ca〈sub〉8〈/sub〉MgSm〈sub〉0.25〈/sub〉(PO〈sub〉4〈/sub〉)〈sub〉7〈/sub〉:0.75Eu〈sup〉3+〈/sup〉 (〈em〉x〈/em〉 = 0.650; 〈em〉y〈/em〉 = 0.345) is close to the standard red-emitting point (〈em〉x〈/em〉 = 0.67, 〈em〉y〈/em〉 = 0.33). The experimental data indicate that Ca〈sub〉8〈/sub〉MgSm〈sub〉1–〈em〉х〈/em〉〈/sub〉(PO〈sub〉4〈/sub〉)〈sub〉7〈/sub〉:〈em〉x〈/em〉Eu〈sup〉3+〈/sup〉 upon excitation by near-UV radiation is a promising red phosphor for white-light-emitting diodes.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818339999-fx1.jpg" width="131" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Wanwu Ding, Chen Xu, Xingang Hou, Xiaoyan Zhao, Taili Chen, Wenjun Zhao, Tiandong Xia, Jisen Qiao〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The new type of Al-Ti-C-La master alloy was prepared by commercial pure Al, Ti powder, graphite powder, Al powder and La〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 powder by aluminum melt in-situ reaction method. The microstructure and the effect on commercial pure aluminum of Al-Ti-C-La master alloy have been studied by means of X-ray diffraction (XDR), scanning electron microscopy (SEM) equipped with energy-dispersive spectrometry (EDS). The synthesis thermodynamics and kinetics of Al-Ti-C-La master alloy were analyzed. The experiment shows that Al-Ti-C-La master alloy is composed of Al, Al〈sub〉3〈/sub〉Ti, TiC and Ti〈sub〉2〈/sub〉Al〈sub〉20〈/sub〉La. The refining performance of the prepared Al-Ti-C-La master alloy is obviously better than that of Al-Ti-C master alloy when the addition of rare earth oxide La〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 is 10 wt% and the preparation temperature is 930 °C. The analysis of thermodynamic calculation and the process of kinetics demonstrate that, in the preparation process of Al-Ti-C-La master alloy, firstly, Al reacts with Ti to produce Al〈sub〉3〈/sub〉Ti, C reacts with Ti and Al〈sub〉3〈/sub〉Ti to form TiC based on the aluminothermy reaction. Rare earth oxide La〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 and C powder react with Ti powder and O〈sub〉2〈/sub〉 in the air occur to generate CO, TiC, [La] atoms and LaC〈sub〉2〈/sub〉. [La] atoms adsorb on the surface of Al〈sub〉3〈/sub〉Ti to form the new rare earth compounds Ti〈sub〉2〈/sub〉Al〈sub〉20〈/sub〉La.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Changmeng Huan, Xinyue Zhao, Xiudi Xiao, Yuan Lu, Shuai Qi, Yongjun Zhan, Lingzhi Zhang, Gang Xu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this work, the V〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 nanoparticles (NPs) with ultrathin carbon shells were synthesized by a facile solvothermal process. The V〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 NPs were about 30 nm and contained a carbon shell of about 2 nm thick. The V〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 NPs were homogeneously dispersed and loosely packed. When used as anode material, the V〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 core-shell NPs showed a reversible capacity up to 525 mA h g〈sup〉−1〈/sup〉 at 200 mA g〈sup〉−1〈/sup〉 over 200 cycles with good cycle stability and rate capability. The excellent electrochemical performance promotes its practical application in lithium-ion batteries.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Honghong Jin, Guang Sun, Bo Zhang, Na Luo, Yanwei Li, Long Lin, Hari Bala, Jianliang Cao, Zhanying Zhang, Yan Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A novel chain-like nanostructure of Co〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 was successfully prepared via a facile and reliable oxalate sacrificial template route, in which coralloid cobalt oxalate (CoC〈sub〉2〈/sub〉O〈sub〉4〈/sub〉·2H〈sub〉2〈/sub〉O) precursor was first obtained through a room-temperature precipitation method and then used as sacrificial template to prepare Co〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 by annealing at 500 °C. Au nanoparticles-decorated Co〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 nanochains were also prepared by soaking the CoC〈sub〉2〈/sub〉O〈sub〉4〈/sub〉 precursor in Au〈sup〉+〈/sup〉 solution before the annealing process. The prepared samples were characterized by XRD, FESEM, TEM, and N〈sub〉2〈/sub〉 adsorption-desorption. Results indicated that the pure and Au-decorated Co〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 nanochains were constructed by several end-to-end connected nanoparticles, and their specific surface areas were 28.42 m〈sup〉2〈/sup〉/g and 37.39 m〈sup〉2〈/sup〉/g, respectively. The gas sensing properties of the prepared samples were tested and compared. It was found that after being functionalized with Au nanoparticles, the Co〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 nanochains showed an improved TEA sensing performance, such as lower optimal working temperature, higher response, and faster response and recover speed. In addition, the Au/Co〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 sensor can also give a good linearity in the TEA concentration range from 10 to 200 ppm and considerable stability within 7 weeks, suggesting its potential application for quantitative detection of TEA. The improved gas sensing mechanism of the Au/Co〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 nanochain was discussed.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): V.A. Lysenko〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A modified version of the Sb-Sn phase diagram was proposed that includes both Sb〈sub〉2〈/sub〉Sn〈sub〉3〈/sub〉 and Sb〈sub〉3〈/sub〉Sn〈sub〉4〈/sub〉 compounds. Based on this modification, phase equilibria in the In-Sb-Sn system were calculated using a thermodynamic modeling approach. Thermodynamic models for the ternary liquid phase and solid solutions (SbSn) and (Sb〈sub〉2〈/sub〉Sn〈sub〉3〈/sub〉) were developed. The isopleths 〈em〉x〈/em〉〈sub〉Sn〈/sub〉 = 0.2, 0.5, 0.8, vertical sections 〈em〉x〈/em〉〈sub〉In〈/sub〉/〈em〉x〈/em〉〈sub〉Sb〈/sub〉 = 3:1, 1:1, 1:3, liquidus surface projection, and isothermal section at 473 K were calculated.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Hongyi Gao, Mengyi Jia, Keyi Dong, Liwen Xing, Xiao Chen, Dandan Jia〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A Sisal-Like TiO〈sub〉2〈/sub〉/Graphene-Like Carbon Sheets (SL-TiO〈sub〉2〈/sub〉/GLCSs) composite was fabricated via a facile one-pot self-assembling route at a two-phase interface. The ingenious P123 was introduced to serve a dual function of carbon precursor and structure-directing agent, which first assembled at the water/oil interfaces and subsequently was in situ carbonized to GLCSs. Then the sisal-like TiO〈sub〉2〈/sub〉 grew gradually on the GLCSs along the preferred direction. This process shows several advantages such as simple processes, mild condition, low cost and good combination of SL-TiO〈sub〉2〈/sub〉 and GLCSs. The combination of SL-TiO〈sub〉2〈/sub〉 with GLCSs significantly helps the adsorption of substrates as well as promotes electron-hole pair separation, exhibiting good photocatalytic activity towards degradation of methylene blue (MB) compared to the pristine SL-TiO〈sub〉2〈/sub〉 and commercial P25. This strategy opens up new perspectives for fabricating novel composites of nanooxides/GLCSs.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Zhennan Liu, Naiqin Zhao, Chunsheng Shi, Fang He, Enzuo Liu, Chunnian He〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Three-dimensional (3D) carbon networks decorated with Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 nanoparticles as lightweight and broadband electromagnetic (EM) wave absorber were 〈em〉in-situ〈/em〉 prepared via a simple and large-scale method, combining freeze-drying and high-temperature calcination processes. SEM and TEM results show that 3D carbon network/Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 (3DC/Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉) composites have interconnected 3D porous carbon networks with submicrometer-sized macropores, and the Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 nanoparticles are distributed uniformly on the 3D carbon networks. The EM wave absorption performance of 3DC/Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 can be tuned by changing Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 contents. The 3DC/Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 with about 38.2 wt% Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 exhibits excellent lightweight and broadband EM wave absorption property. The effective absorption bandwidth can reach up 5.95 GHz (11.2–17.15 GHz) at the thickness of 3.0 mm with only 20 wt% filler loading. The minimum RL of −37.8 dB was obtained at 6.95 GHz. The excellent EM wave absorption capability of 3DC/Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 can be ascribed to good impedance matching, strong dielectric loss ability and unique 3D porous structure. This work demonstrates that the 3DC/Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 with light weight, broad absorption bandwidth and large-scale production potential can be a promising absorber for practical application.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818339768-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Dan Zhou, Li-Ping Xue, Ning Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Transition metal phosphides are promising anode materials for next-generation rechargeable sodium-ion batteries due to the high theoretical capacities. However, the inherent low conductivity and large volume expansion of transition metal phosphides during the repeated sodiation/desodiation process critically hinder their practical applications. Herein, we immobilize Ni〈sub〉2〈/sub〉P nanoparticles robustly in porous carbon sheet networks via the pyrolysis and 〈em〉in-situ〈/em〉 phosphatization of poly(acrylic acid)-Ni(NO〈sub〉3〈/sub〉)〈sub〉2〈/sub〉 gel. The resulted porous network structure, high conductivity, robust chemical combination and space confinement effect of the Ni〈sub〉2〈/sub〉P-carbon composite offer the electrode not only rigid structural stability for volume expansion over long-term cycling, but also large specific capacity and fast Na〈sup〉+〈/sup〉/electrons transfer kinetics. As a consequence, the composite delivers a large initial discharge capacity (932 mAh g〈sup〉−1〈/sup〉 at 50 mA g〈sup〉−1〈/sup〉), a high rate capability (77 mAh g〈sup〉−1〈/sup〉 at 3500 mA g〈sup〉−1〈/sup〉), as well as a significantly enhanced long cycle-life (146 mAh g〈sup〉−1〈/sup〉 after 1500 cycles at 500 mA g〈sup〉−1〈/sup〉). The excellent Na-storage performance makes the synthesized Ni〈sub〉2〈/sub〉P-carbon composite a sound anode material for advanced rechargeable SIBs.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Yu Jun Yang, Weikun Li〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This work presents a novel method for the self-assembly of reduced graphene oxide (rGO) on nickel foam (NF) and the subsequent electrodeposition of hierarchical Ni-Co double hydroxide (NiCo-DH) nanosheets (NS) on rGO as a supercapacitor electrode. The self-assembly of rGO on NF is achieved by the direct reduction of graphene oxide at 50 °C. NF is not only used as the support of rGO but also the reducing agent for the reduction of GO. As the battery-type electrode material for supercapacitor, NiCo-DH supported on rGO modified NF (Ni-Co DHNS@rGO-NF) displays an ultrahigh areal capacity of 5.820 C cm〈sup〉−2〈/sup〉 at 20 mA cm〈sup〉−2〈/sup〉, a 100% coulombic efficiency and a 78% capacity retention after 2000 cycles at 100 mA cm〈sup〉−2〈/sup〉. An hybrid supercapacitor (HSC) is also assembled based on Ni-Co DHNS@rGO-NF as the positive electrode and active carbon (AC) as the negative electrode. The ASC exhibits a prominent energy density of 45.83 Wh kg〈sup〉−1〈/sup〉 at a high power density of 396.15 W kg〈sup〉−1〈/sup〉. The excellent electrochemical performance is attributed to the large surface area of the hierarchical NiCo-DH nanosheets array and the synergistic effect between Ni-Co DHNS and rGO.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Kodai Maeda, Satoshi Suzuki, Kyosuke Ueda, Tomonori Kitashima, Somesh Kr. Bhattacharya, Ryoji Sahara, Takayuki Narushima〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This paper reports the first study of the oxidative behavior of Si-containing Ti-6Al-4V alloys in air. The alloys were studied in the temperature range 910–1210 K for a maximum period of 518.4 ks, and their tensile properties at room temperature are reported. The addition of Si decreased the total mass gain during oxidation and enlarged the region in which the mass gain obeyed the parabolic rate law. The oxide scale mainly consisted of rutile and α-Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 phases. The results of the XPS analysis suggest that in rutile, Si exists as both Si〈sup〉4+〈/sup〉 ions and SiO〈sub〉2〈/sub〉. First-principles calculations indicated that Si〈sup〉4+〈/sup〉 ions stably dissolved into the interstitial sites in rutile, which suppresses oxygen migration through rutile by decreasing the number of oxygen vacancies, thereby inhibiting oxide scale formation. The reaction layer consisting of Ti〈sub〉3〈/sub〉Al and α″ phases on Ti-1mass% Si alloy suppressed the dissolution of oxygen into the substrate, i.e., α-case formation. The ratio of mass gain in α-case formation to total mass gain during oxidation at 1010 K and 1110 K ranged from 0.077 to 0.42. The addition of Si to the Ti-6Al-4V alloy was effective in improving both its oxidative resistance and tensile strength.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818339653-fx1.jpg" width="292" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Joo Sung Kim, Young Been Kim, Seung Ki Baek, Young Dae Yun, Sung Hyeon Jung, Sung Woon Cho, Cheol Hyoun Ahn, Hyung Koun Cho〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉To maximize the advantages of thin-film-based TiO〈sub〉2〈/sub〉 photoelectrodes for transparent self-driven photoelectrochemical (PEC) reactions, we artificially designed a compositionally graded bi-layer compounds consisting of SnO〈sub〉2〈/sub〉 and TiO〈sub〉2〈/sub〉. This structure exhibited a vigorous photocatalytic activity, sufficient photovoltage, and long-term stability. A compositionally graded SnO〈sub〉2〈/sub〉/TiO〈sub〉2〈/sub〉 interface (G-SnTiO) for improved charge transport efficiency and sufficient photovoltage was derived by a solution process using simultaneous sintering after sol-gel coating the SnO〈sub〉2〈/sub〉/TiO〈sub〉2〈/sub〉 layers; the structure was verified by various analysis methods, such as transmission electron microscopy, energy dispersive X-ray spectroscopy, and secondary ion mass spectrometry. The high performance from the G-SnTiO structure was attributed to an effective charge separation from the formation of a heterostructure interface with reduced defects, resulting in a sufficient photovoltage for self-driving. To construct self-driven and sustainable overall cells without an external potential and considerable reduction in transparency, two-electrode PEC cells with a G-SnTiO photoanode and Cu〈sub〉2〈/sub〉O photocathode were fabricated with a regular hexahedron shape for a color degradation test of methylene-blue-incorporated electrolytes, and exhibited enhanced purification speed and robust durability.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818339379-fx1.jpg" width="335" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Usama Bin Humayoun, Seok Bin Kwon, Syed Kamran Sami, Dae-Ho Yoon〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Among various red phosphors, Mn〈sup〉4+〈/sup〉 activated fluoride hosts have received much attention due to their blue excitability and intense red emission. In this study we report a novel (NH〈sub〉4〈/sub〉)〈sub〉3〈/sub〉AlF〈sub〉6〈/sub〉:Mn〈sup〉4+〈/sup〉 phosphor, synthesized through a facile synthesis process avoiding high quantities of highly toxic HF acid. The synthesized host exhibit cubic structure in F-4 3m space group, with plenty of [AlF〈sub〉6〈/sub〉]〈sup〉3+〈/sup〉 octahedral sites. When activated with Mn〈sup〉4+〈/sup〉 the crystal structure is retained and the material exhibits characteristic excitation bands with maximum around 469 nm and intense red emission around 631 nm. Furthermore, the thermal gravimetric analysis revealed the stability of composition up to 250 °C. The phosphor however exhibits high sensitivity to increased temperature and showed sharp quenching of luminescence at elevated temperatures.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Rui Du, Du Yuan, Fei Li, Dongcheng Zhang, Shusen Wu, Shulin Lü〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This study intends to offer a depth understanding on controlling the morphology of eutectic Mg〈sub〉2〈/sub〉Si by adding in-situ TiB〈sub〉2〈/sub〉 particles into 10 〈em〉wt〈/em〉% Mg〈sub〉2〈/sub〉Si/Al composite. The evolution of the microstructure and mechanical properties of Mg〈sub〉2〈/sub〉Si/Al composites with different TiB〈sub〉2〈/sub〉 particles addition from 1 〈em〉wt〈/em〉% to 5 〈em〉wt〈/em〉% is investigated and the mechanism is also discussed. The results show that coarse eutectic Mg〈sub〉2〈/sub〉Si phase can be refined and modified with the addition of TiB〈sub〉2〈/sub〉 particles, and the lattice coherence between them is also confirmed. Besides, the addition of TiB〈sub〉2〈/sub〉 particles can greatly enhance multiple mechanical properties of composites at the same time. With 5% TiB〈sub〉2〈/sub〉 particles addition, the modulus, yield strength and elongation of composites are improved 11%, 59% and 141% respectively compared with Mg〈sub〉2〈/sub〉Si/Al composites. Moreover, different addition of TiB〈sub〉2〈/sub〉 particles changes gradually the fracture behavior of composites from brittle fracture to quasi-cleavage fracture, and finally to entirely ductile behavior.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 20 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 561〈/p〉 〈p〉Author(s): Corina L. Reichert, Hanna Salminen, Gabriela Badolato Bönisch, Christian Schäfer, Jochen Weiss〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The concentration ratio of binary surfactant systems can alter the interfacial layer properties, and consequently affect emulsion stability. To study the effect of varying concentration ratios (〈em〉r,〈/em〉 % w/w) of interfaces containing 〈em〉Quillaja〈/em〉 saponins and other naturally occurring food-grade surfactants on their emulsifying properties, we evaluated particle size, ζ-potential, and appearance of 10% oil-in-water emulsions (pH 7) stabilized by 〈em〉Quillaja〈/em〉 saponin - protein or 〈em〉Quillaja〈/em〉 saponin - lecithin mixtures. 〈em〉Quillaja〈/em〉 saponin - Na-caseinate mixtures (〈em〉r〈/em〉 = 0.3:0.2, 0.2:0.3, and 0.1:0.4) formed small emulsion droplets (d〈sub〉43〈/sub〉: 0.2 – 0.3 μm), whereas at 〈em〉r〈/em〉 = 0.4:0.1, the emulsions contained micron-sized droplets (d〈sub〉43〈/sub〉: 1.217 ± 0.558 μm). Emulsions formed by 〈em〉Quillaja〈/em〉 saponin - pea protein mixtures flocculated at 〈em〉r〈/em〉 = 0.3:2.0, 0.2:3.0, and 0.1:4.0. In contrast, 〈em〉Quillaja〈/em〉 saponin - rapeseed lecithin or egg lecithin mixtures were able to generate small emulsion droplets (d〈sub〉43〈/sub〉: 0.2 – 0.5 μm) at all tested concentration ratios. The formation of stable emulsions using binary mixtures of naturally occurring emulsifiers was more dependent on the concentration ratio of the proteins than lecithins, indicating that the interfacial behavior of 〈em〉Quillaja〈/em〉 saponins is more sensitive to the presence of proteins. This was attributed to attractive molecular interactions yielding complexes at interfaces and/or in the continuous phase. This study shows that food-grade binary surfactant mixtures can be used to form stable emulsions with properties being tunable by altering the mixing ratios between surfactants.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S092777571831522X-ga1.jpg" width="429" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 20 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 561〈/p〉 〈p〉Author(s): Li Wang, Jingyi Wang, Chi He, Wei Lyu, Wenlong Zhang, Wei Yan, Liu Yang〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉To improve the biochar’s adsorption performance towards phosphate as well as to endow the biochar with magnetic property, novel rare earth element doped magnetic biochars, Ce/Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉-BC and La/Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉-BC, were prepared by separately co-precipitating cerium (Ce) and lanthanum (La) with FeCl〈sub〉3〈/sub〉, FeCl〈sub〉2〈/sub〉 and biochar. For comparison, Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉-BC without doping Ce or La was also synthesized. The characterization results indicated that Ce and La ions were successfully doped into the magnetite. The La/Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉-BC had higher magnetic saturation and point of zero charge than Ce/Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉-BC. A series of batch experiment results demonstrated that the phosphate adsorption capacity of biochar has been greatly improved after Ce or La doping, especially La. The phosphate adsorption capacity of La/Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉-BC was 20.5 mg/g at pH 6.5, which was 1.6 and 2.9 times than that of Ce/Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉-BC and Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉-BC, respectively. The adsorption kinetics and isotherms of phosphate onto La/Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉-BC and Ce/Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉-BC were best fitted by the pseudo-second order and Freundich model, respectively, indicating that the adsorption process was a multilayer process and controlled by chemical reaction. The combined results of batch experiments and physiochemical analyses revealed that the possible mechanisms were the formation of inner-sphere complex at neutral conditions and electrostatic attraction between positively charged adsorption sites and phosphate under acid conditions. The enhanced phosphate adsorption performance and endowed magnetic property indicated La/Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉-BC could be used as a promising adsorbent in phosphate removal.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718312615-ga1.jpg" width="455" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): S.S. Mani Prabu, H.C. Madhu, Chandra S. Perugu, K. Akash, R. Mithun, P. Ajay Kumar, Satish V. Kailas, Manivannan Anbarasu, I.A. Palani〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Welding of shape memory alloys without deterioration of shape memory effect could vastly extend their applications. To retain shape memory behavior, a solid-state welding technique called friction stir welding was employed in this study. Austenitic NiTi alloy sheets of thickness 1.2 mm were joined at tool rotational speeds of 800, 1000, and 1200 rpm. Due to dynamic recrystallization, the grain refinement has occurred in the weld region. The tensile testing has shown superelastic plateau for the welds at 800 and 1000 rpm. The phase transformation behavior of different weld regions was studied in detail using differential scanning calorimeter. A marginal drift in transformation temperatures was observed in the weld. To understand the drift in phase transformation temperatures, finite element analysis was carried out with focus on temperature distribution during welding. Finally, time-dependent shape recovery of a FSW welded joint was studied and it was found that the original position was completely recovered after 27 s at a temperature of 65 °C.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S092583881833874X-fx1.jpg" width="437" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Matthias Stacher, Gabriel R. Reisinger, Klaus W. Richter〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Phase equilibria of Au-Ni-Si were investigated in the isothermal section at 700 °C using a combination of powder X-ray diffraction and quantitative phase analysis by SEM-EDX. Four vertical sections of the phase diagram at 10 at.% Au and at 15, 30 and 60 at.% Ni were studied by DTA. These data were combined with isothermal sections at 320° and 500° published earlier to develop a ternary reaction scheme and a liquidus surface projection. Fifteen ternary invariant reactions, a three-phase field maximum and a critical tie-line are proposed. The observed phase diagram is discussed regarding the possible use of Au-Si liquids for transient liquid phase (TLP) soldering of Nickel.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Yong Zhang, Jinming Guo, Jianghua Chen, Cuilan Wu, Karoline Sophie Kormout, Pradipta Ghosh, Zaoli Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Bulk nanocrystalline alloys usually possess enhanced properties than their coarse-grained counterparts. Here, first-principles calculations and aberration-corrected transmission electron microscope (TEM) were employed to investigate the atomic-scale deformation mechanism of Cu-based alloys. The effect of alloying element concentration and temperature-induced solute distribution on the unstable stacking fault energy (γ〈sub〉usf〈/sub〉), stable stacking fault energy (γ〈sub〉isf〈/sub〉) and unstable twin fault energy (γ〈sub〉utf〈/sub〉) were calculated using a Fermi–Dirac distribution of solutes for 42 binary Cu-X alloys. At medium temperature (〉200 K) or low solute concentrations (〈15 at.%), the stacking fault energies calculated from the Fermi–Dirac model accord well with the available experimental and theoretical results. The deformation mechanism was then evaluated by α = γ〈sub〉isf〈/sub〉/γ〈sub〉usf〈/sub〉 and β = γ〈sub〉utf〈/sub〉/γ〈sub〉usf〈/sub〉, smaller α (β) favors an easier formability of extended dislocations (twins). Most subgroup VI-VIII metals in the periodic table can slightly increase the γ〈sub〉usf〈/sub〉, γ〈sub〉isf〈/sub〉 and γ〈sub〉utf〈/sub〉 of Cu, and have almost no influence on α and β. While main group and subgroup II-V elements can decrease γ〈sub〉usf〈/sub〉, γ〈sub〉isf〈/sub〉 and γ〈sub〉utf〈/sub〉 as well as the values of α and β. For alloying elements of Pd, Ag, Pt and Au, the values of α and β increase, suggesting a tendency of deformation mechanism from extended dislocations to full dislocations. Furthermore, high-resolution TEM (HRTEM) images of four representative nanocrystalline alloys (pure Cu, Cu-Fe, Cu-Ag and Cu-Zn) corroborates the prodiction with α and β as well as the empirical twinnability. The α and β remain almost the same as that of pure Cu when alloyed with Fe while they decrease with Zn, and the extended dislocations and twins were commonly observed for Cu, Cu-Fe and Cu-Zn. The α and β increased with Ag addition although the γ〈sub〉isf〈/sub〉 decreased, and the extended dislocations were barely observed for Cu-Ag sample. The theoretical and microstructural correlation provides insights into the deformation mechanism of Cu-based alloys.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Yongju Yoo, Yun Chan Kang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Nb〈sub〉2〈/sub〉O〈sub〉5〈/sub〉 materials based on intercalation reactions have been extensively studied as anode materials for lithium-ion batteries. Mesoporous Nb〈sub〉2〈/sub〉O〈sub〉5〈/sub〉 microspheres with narrow size distribution are the ideal structure for achieving a high volumetric capacity. Mesoporous filled- and yolk-shell-structured (reported for the first time) Nb〈sub〉2〈/sub〉O〈sub〉5〈/sub〉 microspheres are synthesized using a highly porous carbon template. The NbSe〈sub〉3〈/sub〉-C composite transforms into yolk-shell-structured Nb〈sub〉2〈/sub〉O〈sub〉5〈/sub〉 microspheres by a one-step oxidation process. The filled microspheres having ultrafine crystallite size and high mesopore volume show better cycling and rate performances than the yolk shell microspheres. The discharge capacity of the filled microspheres at a current density of 1 A g〈sup〉−1〈/sup〉 is 124 mA h g〈sup〉−1〈/sup〉 in the 5000〈sup〉th〈/sup〉 cycle, and the capacity retention in the second cycle is 76%. The discharge capacity of the filled microspheres decreases by approximately 26% from 171 mA h g〈sup〉−1〈/sup〉 to 127 mA h g〈sup〉−1〈/sup〉 when the current density increases from 0.5 A g〈sup〉−1〈/sup〉 to 10 A g〈sup〉−1〈/sup〉. Particularly, the volumetric capacity of the filled microspheres at a high current density of 10 A g〈sup〉−1〈/sup〉 is 2.3 times higher than that of the yolk-shell-structured microspheres (filled ≈ 11.5 mA h cc〈sup〉−1〈/sup〉 vs. yolk ≈4.9 mA h cc〈sup〉−1〈/sup〉).〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Dunya M. Babanly, Ziya S. Aliev, Qorkhmaz M. Huseynov, Salim M. Asadov, Solmaz N. Mustafaeva, Dilgam B. Tagiyev〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The phase equilibria in the ternary Tl-S-I system were investigated experimentally by means of powder X-ray diffraction (PXRD) and differential thermal analysis (DTA). Five isopleth sections, liquidus surface projection and room temperature isothermal section were constructed based on experimental data. 〈em〉dc〈/em〉-and 〈em〉ac〈/em〉-electric properties of the TlS and Tl〈sub〉6〈/sub〉SI〈sub〉4〈/sub〉 crystals were studied within the temperature and frequency ranges from 120 K to 300 K and from 50 kHz to 35 MHz, respectively. The hopping mechanism for charge transfer over the localized states near the Fermi level was established at low temperatures and high frequencies for these compounds. The density and energy scatter of the states which are located in the vicinity of the Fermi level as well as the average time and distances of jumps were estimated for the title compounds.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Marietta Seifert, Gayatri K. Rane, Siegfried B. Menzel, Steffen Oswald, Thomas Gemming〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A sufficient oxidation resistance of RuAl thin films is crucial for their application in high temperature sensors e.g. based on the surface acoustic waves principle. To improve the high temperature stability, an Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 or SiO〈sub〉2〈/sub〉 cover layer is added to protect the films from oxidation especially for application in air. The covered RuAl films are annealed at temperatures up to 900 °C under high vacuum and in air for 10 h. X-ray diffraction, cross section imaging and Auger electron spectroscopy are applied to reveal the suitability of the cover layers as oxidation barrier. While there is hardly any difference between the samples with or without cover layer after annealing under high vacuum, only the samples with SiO〈sub〉2〈/sub〉 cover are stable up to 800 °C in air.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818339525-fx1.jpg" width="483" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): O.V. Maksakova, S. Simoẽs, A.D. Pogrebnjak, O.V. Bondar, Ya.O. Kravchenko, T.N. Koltunowicz, Zh.K. Shaimardanov〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Multilayered ZrN/CrN coatings were produced by the cathodic arc physical vapor deposition (CA-PVD). Morphology, element distribution, structural and thermal properties were investigated. Microhardness and nanoindentation tests were conducted to study the mechanical properties of the coatings. The experimental results of scanning electron microscopy (SEM) revealed the cellular microrelief of the surface and well-defined multilayered architecture of the coatings. Energy dispersive spectroscopy (EDS) provided the chemical characterization of the coatings and revealed the formation of stoichiometric composition in coatings. X-ray diffraction (XRD) studies showed that (200) and (111) plane reflections of ZrN and Cr〈sub〉2〈/sub〉N phases, correspondingly, were with maximum intensity. Transmission electron microscopy (TEM) analysis revealed that the films comprise of nanometric equiaxed grains with average sizes from 12.8 to 15.1 nm for ZrN layers and from 14.5 to 28.1 nm for CrN layers. The high-temperature heat treatment caused exothermic and endothermic reactions, which were mainly attributed to the improvements or disordering of the coatings' structure, consequently. The highest values of microhardness (4966HV0.025) and nanohardness (24.58 GPa) were obtained for the sample with a bilayer thickness of 732 nm, the average crystallite size of 13.3 nm and nitrogen content of 49 at%. Experimental results indicated that deposited composites can be effectively used in the production of industrial tools, implements for cutting etc.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Manisha Kumari, Shrabani Mondal, Prashant K. Sharma〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The drug loading and release properties of Eu〈sup〉3+〈/sup〉 doped GdPO〈sub〉4〈/sub〉 nanoparticles (NPs) were studied using a simple electrochemical protocol in an 〈em〉in-vitro〈/em〉 environment, taking acetaminophen as a model drug. The electrochemical monitoring of drug release was also validated with absorption spectroscopy technique. For this purpose, dual stimuli (pH and temperature) responsive monoclinic mesoporous GdPO〈sub〉4〈/sub〉 nanoparticles of size ∼22 nm were synthesized by a simple hydrothermal method. Crystal structure, size, shape, morphology, porosity, optical property and magnetic properties of the obtained product were studied by different characterization techniques. Successful loading of drug in NPs was investigated by Fourier transform infrared spectroscopy (FT-IR). Photoluminescence (PL) measurement shows orange-red color emission corresponding to 〈sup〉5〈/sup〉D〈sub〉0〈/sub〉→〈sup〉7〈/sup〉F〈sub〉2〈/sub〉 transitions of Eu〈sup〉3+〈/sup〉 ions. The vibrating sample magnetometer (VSM) measurements showed negligible hysteresis in both samples, suggesting retention of the superparamagnetic behavior of GdPO〈sub〉4〈/sub〉 NPs. The high loading capacity of 79% and encapsulation efficiency of 83% is observed when acetaminophen, an anti-fever drug, was loaded on these mesoporous GdPO〈sub〉4〈/sub〉 NPs. The drug was attached on NPs surfaces via absorption, without any special surface modification. During drug release studies, a spontaneous and smooth release from these mesoporous NPs was observed at a moderate-high temperature (37 °C) and low pH (pH 5) with no sign of burst release. These nanoparticles were capable of targeting and specific release of the loaded drug in response to pH and temperature and hence may serve as a potential drug carrier for 〈em〉in-vivo〈/em〉 applications.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818339604-fx1.jpg" width="275" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Shixiang Zuo, Zhan Liu, Wenjie Liu, Xiazhang Li, Zhongyu Li, Chao Yao, Qun Chen, Yongsheng Fu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Oriented rutile TiO〈sub〉2〈/sub〉 nanorod arrays (TiO〈sub〉2〈/sub〉 NRA) were elaborately grown on the conductive mica (C-mica) with Sb-SnO〈sub〉2〈/sub〉 seed crystal by a hydrothermal strategy to achieve TiO〈sub〉2〈/sub〉 NRA/C-mica composites. The as-obtained samples were characterized by X-ray diffraction, field emission scanning electron microscope, X-ray photoelectron spectroscopy, UV–vis diffuse reflectance spectroscopy and photo-electrochemical measurements. Compared with TiO〈sub〉2〈/sub〉 NP/mica, TiO〈sub〉2〈/sub〉 NRA/C-mica coated film exhibits more excellent physical barrier ability in the dark, and an enhanced photo-induced current density as well as a more negative photo-potential shift in the light, indicating remarkable photo-cathodic protection for 304 stainless steel (304SS). The distinctive 1D-2D architecture of TiO〈sub〉2〈/sub〉 NRA/C-mica facilitates the transmission and separation of photo-induced electron-hole pairs. Furthermore, it's the first time that the TiO〈sub〉2〈/sub〉 NRA/C-mica hybrid film is found to possess continuous and stable cathodic protection for the 304SS over a long period in the dark.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S092583881834009X-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Baochen Wang, Ziyao Wang, Yangai Liu, Tao Yang, Zhaohui Huang, Minghao Fang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Crystal structure tailoring is a commonly used method for tuning the luminescence of phosphors. This study mainly aims at luminescent spectra tuning of Sr〈sub〉1−〈em〉x〈/em〉〈/sub〉Ba〈sub〉〈em〉x〈/em〉〈/sub〉Al〈sub〉2〈/sub〉Si〈sub〉2〈/sub〉O〈sub〉8〈/sub〉:Eu〈sup〉2+〈/sup〉 phosphors by substitution of Ba for Sr ions. The phase composition was characterized by X-ray powder diffraction and the crystal structure was determined by using the Rietveld refinement method. The excitation and emission spectra, diffuse reflectance spectra, and thermal quenching were also investigated in detail. The results show that Sr〈sub〉1−〈em〉x〈/em〉〈/sub〉Ba〈sub〉〈em〉x〈/em〉〈/sub〉Al〈sub〉2〈/sub〉Si〈sub〉2〈/sub〉O〈sub〉8〈/sub〉:Eu〈sup〉2+〈/sup〉 phosphors can form a series of continuous solid solutions in the range from 0 to 0.75. With the increase in 〈em〉x〈/em〉 value, the emission spectra show an obvious redshift from 415 to 450 nm. The emission redshift plays an important role in enabling Sr〈sub〉1−〈em〉x〈/em〉〈/sub〉Ba〈sub〉〈em〉x〈/em〉〈/sub〉Al〈sub〉2〈/sub〉Si〈sub〉2〈/sub〉O〈sub〉8〈/sub〉:Eu〈sup〉2+〈/sup〉 to be used as a standard blue phosphor for application in white-light-emitting diodes.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818340465-fx1.jpg" width="303" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Jia Sun, Qian-Gang Fu, Tao Li, Guang-Peng Zhang, Rui-Mei Yuan〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Constituent phases, porosity and residual stress are significant factors influencing the performance of two-dimension (2D) structural components. In present study, these factors with respect to thermally sprayed MoSi〈sub〉2〈/sub〉 based composite were elaborately adjusted through plasma spraying power to investigate the oxidation behavior in medium temperature range of 400–900 °C. By increasing the operation powers, the improved melting degree of feedstock led to the increased metastable phases and the decreased porosity in the MoSi〈sub〉2〈/sub〉 based composite but it did not remarkably affect the residual stress distribution. After the analysis on the medium-temperature oxidation, it can be concluded that the metastable phases and the porosity were principally responsible for the enhanced oxidation resistance of the MoSi〈sub〉2〈/sub〉 based composite. The thermal-sprayed 2D MoSi〈sub〉2〈/sub〉 based composites with large amounts of 〈em〉β〈/em〉 phases and low porosity can achieve the outstanding oxidation resistance in medium temperature range.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Li Jin, Jun Qiao, Lei Hou, Liang Wang, Lin Zhang, Xu Lu, Hongliang Du, Xiaoyong Wei, Yan Yan, Gang Liu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Perovskite ferroelectric ceramics with 〈em〉T〈/em〉〈sub〉〈em〉m〈/em〉〈/sub〉 (temperature corresponding to maximum dielectric permittivity 〈em〉ε〈/em〉′) around room temperature and high electrostrictive coefficient 〈em〉Q〈/em〉〈sub〉33〈/sub〉 are of interest to the applications in high-precision actuators, since low-hysteresis/non-hysteresis and high strain response can be generated in these materials based on a purely electrostrictive effect. In this work, undoped Ba(Zr〈sub〉0.2〈/sub〉Ti〈sub〉0.8〈/sub〉)O〈sub〉3〈/sub〉 (BZT) and La〈sup〉3+〈/sup〉-doped Ba(Zr〈sub〉0.2〈/sub〉Ti〈sub〉0.8〈/sub〉)O〈sub〉3〈/sub〉 (BLZT) lead-free ferroelectrics were synthesized by solid state reaction method. Their dielectric and ferroelectric properties were investigated systematically with an emphasis on electrostrictive effect. With respect to increase of La〈sup〉3+〈/sup〉 content from 0 to 1%, the 〈em〉T〈/em〉〈sub〉〈em〉m〈/em〉〈/sub〉 of BLZT decreases from 44.5 °C to 14.6 °C, and the diffuseness degree 〈em〉γ〈/em〉 increases from 1.814 to 1.993. A conductive mechanism, which is prominent in undoped BZT, is inhibited drastically by introducing the La〈sup〉3+〈/sup〉 into BZT. A high electrostrictive strain of 0.08% and a low hysteresis 〈em〉η〈/em〉 (〈10%) are obtained simultaneously in 〈em〉x〈/em〉 = 0.25% composition at room temperature. The 〈em〉Q〈/em〉〈sub〉33〈/sub〉 ranges from 0.0377 m〈sup〉4〈/sup〉/C〈sup〉2〈/sup〉 and 0.0537 m〈sup〉4〈/sup〉/C〈sup〉2〈/sup〉. This work not only reports a high electrostrictive effect in BLZT ferroelectrics, but also provides BLZT ceramics with a potential application in high-precision actuators.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Fuwen Yu, Chunjin Hang, Menghui Zhao, Hongtao Chen〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A die-attach material based on an Sn-coated Ni core-shell powder with a high re-melting temperature can be used for high-temperature applications. The outer Sn layers of the Sn-coated Ni particles possess a low melting point of 232 °C and can be completely converted into a Ni〈sub〉3〈/sub〉Sn〈sub〉4〈/sub〉 intermetallic compound with a high re-melting point of 794.5 °C after reflowing at a low temperature of 250 °C for 40 min. This die-attach material exhibits an excellent high-temperature operational capability, with a high shear strength of 40.2 MPa at 500 °C. The coefficient of thermal expansion (CTE) of the reflowed preform is between those of SiC and Cu, which is highly beneficial for mitigating the stress caused by the CTE mismatch between these materials. In addition, the thermal conductivity of the bondline is sufficiently high for heat dissipation during operation.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): José C.S. Filho, Sérgio C. Zilio, Djalmir N. Messias, Viviane Pilla, Anielle C.A. Silva, Noelio O. Dantas, Acácio A. Andrade〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The thermal expansion (〈em〉α〈/em〉) and the thermo-optic (d〈em〉n〈/em〉/dT) coefficients of a phosphate glass dubbed as PANK were simultaneously measured using a single arm double interferometer from 100 to 400 K of the temperature range. An athermal behavior of the optical path difference in a two-beam interferometer was found around 200 K. This result is in agreement with a similar observation carried out applying the Thermal Lens spectrometry (TLS) of Nd-doped PANK glass at ∼180 K. The main difference between these temperature values is ascribed to the sample surface curvature induced by the laser beam in thermal lens measurements. The athermal behavior shows that this glass has the potential for laser applications as an ion host at low temperature, and small changes in the glass composition should be explored to bring this property to room temperature.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818339306-fx1.jpg" width="288" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): B.N. Sahoo, S.K. Panigrahi〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Magnesium matrix in-situ composites with hybrid TiC+TiB〈sub〉2〈/sub〉 reinforcement are potential materials for automobile and aerospace applications. It is essential to establish the processing map of such composites as these materials may undergo several thermo-mechanical processes while manufacturing engineering components. In the current work, AZ91 Magnesium matrix TiC+TiB〈sub〉2〈/sub〉 reinforces hybrid in-situ along with its base counterpart were developed and subjected to solutionization followed by peak aging treatment. The safe processing zone for both base and in-situ composite at all heat treatment conditions have been established through processing map based on dynamic materials model (DMM) by conducting hot compression tests at various temperatures (250 °C – 450 °C) and strain rates (0.001 s〈sup〉−1〈/sup〉 – 10 s〈sup〉−1〈/sup〉). Two regions: stable and instable were identified from processing map for all the material conditions. Dynamic recrystallization is the main dominant mechanism in stable region, whereas instable region is characterized by twin and intergranular cracks. To understand the mechanism of hot deformation behavior, activation energy is calculated based on constitutive model for all material conditions. The developed in-situ composite in peak aged condition is found to possess higher activation energy (∼230 kJ/mol) as compared to base alloy (∼126 kJ/mol). A correlation between constitutive model and processing map have been established with an emphasis on their microstructures.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818339483-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Chuanjun Li, Rui Guo, Shengya He, Weidong Xuan, Xi Li, Yunbo Zhong, Zhongming Ren〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The formation of the microstructures in the hypo- and hypereutectic Al〈img src="https://sdfestaticassets-us-east-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉Cu alloys in the steady magnetic field (SMF) was investigated using the conventional quenching technique. In comparison with quenched structures without the SMF, the additional bulky phases, i.e. θ-Al〈sub〉2〈/sub〉Cu phase and the supersaturated α solid solution, were found to form in the Al-26 wt%Cu and Al-45 wt%Cu alloys quenched in the SMF, respectively. The temperature measurements showed that the maximum cooling rate of the quenched sample in the SMF was markedly higher than that without the SMF and thus a larger undercooling was obtained in the SMF. The microstructure formation in the SMF can be rationalized using the Al〈img src="https://sdfestaticassets-us-east-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉Al〈sub〉2〈/sub〉Cu phase diagram with metastable extensions and the coupled growth zone.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Wenmin Guo, Bin Liu, Yong Liu, Tianchen Li, Ao Fu, Qihong Fang, Yan Nie〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Refractory high-entropy alloys (RHEAs) are promising high-temperature structural materials due to their high melting point and extraordinarily high yield strength. However, their industrial application is greatly restricted due to their limited room-temperature ductility. In the present investigation, a ductile and strong single-phase NbTaTiV RHEA was synthesized by powder metallurgy method. Effects of the sintering temperature on the phase formation, microstructural evolution and the mechanical properties of the NbTaTiV RHEA were characterized. The results show that the NbTaTiV RHEA sintered at 1700 °C has an equiaxed single bcc phase microstructure, no obvious porosity and compositional segregation can be observed. The alloy exhibits a relatively high hardness of 510 HV, yield strength of 1.37 GPa, and compressive fracture strength of 2.19 GPa with a high fracture strain of 23% at room temperature. Typical strain softening and steady state flow occur during compressive deformation at high temperatures. During deformation at 1000 °C, the alloy still exhibits high yield strength of 437 MPa with a compression strain over than 40%. The outstanding mechanical properties is mainly attributed to the homogeneous and fine microstructures, and solid solution strengthening effect. It can be concluded that the powder metallurgy is a promising way for preparing ductile RHEAs with outstanding comprehensive mechanical properties.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Thiquynhxuan Le, Qi Wang, A.V. Ravindra, Xiteng Li, Shaohua Ju〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A novel microwave heating process for the synthesis of zeolite-Y from spent fluid catalytic cracking (SFCC) catalyst has been proposed in this work. The SFCC catalyst is firstly activated in microwave field by acid solution and then used as an aluminum source for the synthesis of zeolite-Y. The activation effect of hydrochloric acid and oxalic acid on the SFCC catalyst, and the synthesis effects of zeolite-Y production from the activated SFCC catalyst under microwave are studied by ICP, XRD, SEM, and N〈sub〉2〈/sub〉 sorption studies. The results show that microwave-assisted acid activation process can facilitate the formation of the active γ-Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 and as well enhance the crystallinity of zeolite-Y in the SFCC catalyst, which is beneficial for the synthesis of zeolite-Y. Compared with the inactivated SFCC catalyst, the activated SFCC catalyst has a larger specific surface area and a lower contaminated metal content. The specific surface areas of SFCC catalyst after activation by hydrochloric acid and oxalic acid are 197.1 and 113.6 m〈sup〉2〈/sup〉/g, respectively, indicating better activation by hydrochloric acid compared to oxalic acid in the microwave field. The results demonstrate that increasing the synthesis temperature and prolonging the crystallization time favor the growth of zeolite-Y crystal particles, however, zeolite-Y partially transforms into zeolite-P. The priority of different aluminum sources in zeolite-Y synthesis is: hydrochloric acid activated SFCC catalyst 〉 oxalic acid activated SFCC catalyst 〉 inactivated SFCC catalyst. The zeolite-Y having a particle size range of 0.3–1 μm is successfully synthesized from the activated SFCC catalyst at 100 °C for 2 h under microwave at 2 kg/cm〈sup〉2〈/sup〉 pressure and 1000 W power.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Qing Zhou, Yin Du, Yue Ren, Wangwang Kuang, Weichao Han, Haifeng Wang, Ping Huang, Fei Wang, Jian Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Friction and wear are the two most important properties that determine the long-term performances of metallic glasses as much as strength and ductility. With this in mind, a multilayered strategy was proposed to improve the nano-scratching properties of metallic glass thin films and the well-characterized Zr-based metallic glasses were chosen to be the representative model materials in current work. It was found that the metallic glass could exhibit improved wear resistance and reduced friction coefficient if it is made in the form of multilayers. The complexity in the temporal scale of the lateral force signal is investigated, elucidating the inhomogeneous (and homogeneous) shear-banding processes during the nanoscratching process. The statistical and dynamic analyses of the stick-slip behaviors showed a transition from a chaotic to a self-organized critical state in the multilayers, indicating that the hetero-interfaces promote extensive shear band-interface interactions and induce the scratch hardening effect, both of which are responsible to the excellent tribological properties. The current work not only highlights the significant roles of hetero-interfaces in improving the nano-tribological properties but also make the multilayered metallic glass thin films a promising candidate towards structural and functional applications for metallic glasses.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818339446-fx1.jpg" width="280" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): P. Sochacka, A. Miklaszewski, M. Jurczyk〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Titanium-based alloys with fine grain structure represent a class of engineering materials that can exhibit a unique combination of properties. This paper presents the structural evolution of the β phase in Ti-x at. % Mo (x = 10, 23, 27, 31 and 35) alloys synthesized by mechanical alloying with different milling times between 15 min and 48 h and powder metallurgical process with cold powder compaction and sintering or interchangeably hot pressing. The binary alloys were characterized by X-ray diffraction, scanning electron microscopy, chemical composition determination as well as density and porosity measurements. The influence of the chemical composition and method of processing on the final microstructure, and mechanical properties of bulk alloys were studied. The mechanically alloyed Ti23Mo, Ti27Mo and Ti31Mo materials upon sintering at 800 °C for 5 min led to the formation of single β type phase alloys. All these β-type alloys have elastic modulus lower than CP microcrystalline α-Ti, but their hardness is nearly 3 times higher (approx: 460 HV〈sub〉0.3〈/sub〉). The present study has demonstrated that these single phase β-type alloys with fine grain microstructure can be fabricated by the application of hot pressing of mechanically alloyed powders at the temperature below α→β transus (800 °C).〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S092583881833891X-fx1.jpg" width="145" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Li Wan, Yun-Lai Deng, Ling-Ying Ye, Yong Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The natural ageing effect on artificial ageing kinetics of Al-Zn-Mg alloy has been studied using small angle X-ray scattering, transmission electron microscopy and mechanical testing methods. The results have demonstrated that with 72 hours natural ageing treatment prior to pre-ageing process can inhibit following natural ageing effect. Samples with direct pre-ageing treatment after quenching from solution temperature exhibit significant natural ageing effect subsequently. The strengthening effect is mainly attributed to the formation of fine GP-zones with particle sizes of less than 1 nm. The microstructures characterization has shown that these GP-zones may transform to precursor of η′ precipitate during pre-ageing process if their size reached a critical size. These precursor of η′ precipitate with the size of ∼1 nm–∼1.2 nm are stable at room temperature.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): A. Brzoza, M. Kowalczyk, A. Wierzbicka-Miernik, P. Czaja, W. Maziarz, A. Wójcik, J. Wojewoda-Budka, M. Sikora, J. Dutkiewicz, M.J. Szczerba〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Ni-Mn-Ga-Co-Cu melt spun ribbons were investigated in the as-cast and annealed states. The initial microstructure of the ribbons was highly anisotropic along the growing direction and was characterized by three different regions of equiaxed, columnar and dendritic grains. At ambient temperature, the microstructure was composed of two martensitic phases, i.e. non-modulated and seven-layer modulated, and the high temperature L2〈sub〉1〈/sub〉 austenite phase. The stabilization of the austenite phase was a consequence of a strong grain size reduction, especially close to the “contact” side of the ribbons. Subsequent annealing at 823 K triggered atomic ordering, which promoted an improvement in the magnetization. Additional annealing at 1173 K brought about a substantial refinement of the microstructure. The ribbon structure changed to a single non-modulated martensite phase, whereas on a microstructural level, the grains and martensitic plates coarsened considerably. The annealed ribbons resembled oligo-crystalline materials and may cause interest for magnetic field-induced strain applications.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818339057-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Priyanka Nehla, Clemens Ulrich, Rajendra S. Dhaka〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We report the structural, transport, electronic, and magnetic properties of Co〈sub〉2〈/sub〉FeGa Heusler alloy nanoparticles. The Rietveld refinements of x-ray diffraction (XRD) data with the space group Fm〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.gif" overflow="scroll"〉〈mrow〉〈mover accent="true"〉〈mn〉3〈/mn〉〈mo〉¯〈/mo〉〈/mover〉〈/mrow〉〈/math〉m clearly demonstrates that the nanoparticles are of single phase. The particle size (D) decreases with increasing the SiO〈sub〉2〈/sub〉 concentration. The Bragg peak positions and the inter-planer spacing extracted from high-resolution transmission electron microscopy image and selected area electron diffraction are in well agreement with data obtained from XRD. The coercivity initially increases from 127 Oe to 208 Oe between D = 8.5 nm and 12.5 nm, following the D〈sup〉−3/2〈/sup〉 dependence and then decreases with further increasing D up to 21.5 nm with a D〈sup〉−1〈/sup〉 dependence, indicating the transition from single domain to multidomain regime. The effective magnetic anisotropic constant behaves similarly as coercivity, which confirms this transition. A complex scattering mechanisms have been fitted to explain the electronic transport properties of these nanoparticles. In addition we have studied core-level and valence band spectra using photoemission spectroscopy, which confirm the hybridization between 〈em〉d〈/em〉 states of Co/Fe. Further nanoparticle samples synthesized by co-precipitation method show higher saturation magnetization. The presence of Raman active modes can be associated with the high chemical ordering, which motivates for detailed temperature dependent structural investigation using synchrotron radiation and neutron sources.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Xin Zhang, Ming Zhang, Tianyu Cui, Jinman Li, Qingsuo Liu, Haibo Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The microstructure and the shape memory effect of Cu-13.0Al-4.0Ni high temperature shape memory alloys doped with different contents of boron (0.25 wt%, 0.5 wt%, 1.0 wt%, and 2.0 wt%) were studied in this paper. According to the obtained results, it was observed that the microstructure and the shape memory effect were sensitive to the addition of boron, and the addition of boron not only enhanced the mechanical properties of the Cu-13.0Al-4.0Ni alloy, but also greatly improved the shape memory effect of the alloy. The fracture of martensite changed from intergranular fracture to transgranular cleavage fracture. In addition, it was found that the highest shape memory effect was achieved by the addition of 0.25 wt% boron.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Sen Gao, Xian Zhang, Qingfeng Zeng, Shiyu Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Crystalline 〈em〉α〈/em〉-TeO〈sub〉2〈/sub〉 was investigated at ambient pressure using 〈em〉ab initio〈/em〉 calculations. The effect of pressure on 〈em〉α〈/em〉-TeO〈sub〉2〈/sub〉 was studied from 0 to 10 GPa. The lattice parameters and elastic constants calculated by LDA and GGA method at 0 GPa both agree with the available theoretical and experiment results. The elastic constants 〈em〉C〈/em〉〈sub〉〈em〉ij〈/em〉〈/sub〉, the bulk modulus 〈em〉B〈/em〉, the shear modulus 〈em〉G〈/em〉, Young's modulus 〈em〉E〈/em〉, and the ductile and brittle character (〈em〉B〈/em〉/〈em〉G〈/em〉) were calculated and examined in detail. It was found that the calculated universal anisotropy index indicated that 〈em〉α〈/em〉-TeO〈sub〉2〈/sub〉 has anisotropy under 0 GPa, and with the pressure increases, its elastic anisotropy increases. Furthermore, from the mechanical stability criteria, it is show that the structure of tetragonal 〈em〉α〈/em〉-TeO〈sub〉2〈/sub〉 is not stable above 5.1 GPa. Finally, the electronic and optical properties were also investigated, and the results show that, on increasing the external pressure, the energy bandgap increases, with the optical spectrum exhibiting anisotropy in the 〈em〉x〈/em〉 and 〈em〉z〈/em〉 directions and a small blue shift under pressure.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Jens Reiser, Andreas Hoffmann, Johannes Hain, Ute Jäntsch, Michael Klimenkov, Jörg Hohe, Tobias Mrotzek〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉This paper describes a systematic analysis of liquid-phase infiltrated molybdenum (Mo) copper (Cu) composites, deformed by various levels, and elucidates the impact of (i) the copper content, and (ii) the rolling reduction on the evolution of the material properties. The rolling-induced change of the thermo-physical properties can be traced back to (ii-a) the evolution of the geometry (viz. the flattening of the molybdenum and the copper phase during rolling) and (ii-b) the evolution of the crystallographic texture.〈/p〉 〈p〉Four infiltrated ingots with a copper content of 23, 39, 48 and 54 vol % were produced. Each ingot was gradually rolled down to a final degree of deformation of 0.5, 1, 1.5, 2 and 2.38, which corresponds to a rolling reduction of 39%, 63%, 78%, 86% and 90%. In summary, four material compositions (23, 39, 48 and 54 vol % Cu) in six conditions (as-infiltrated and five as-rolled conditions) were examined.〈/p〉 〈p〉The evolution of the microstructure is correlated with the evolution of the mechanical and thermo-physical properties such as hardness (HV2), Young's modulus, 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.gif" overflow="scroll"〉〈mrow〉〈mi〉E〈/mi〉〈/mrow〉〈/math〉, electrical conductivity, 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si2.gif" overflow="scroll"〉〈mrow〉〈mi〉σ〈/mi〉〈/mrow〉〈/math〉, thermal conductivity, 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si3.gif" overflow="scroll"〉〈mrow〉〈mi〉k〈/mi〉〈/mrow〉〈/math〉, and the coefficient of thermal expansion, 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si4.gif" overflow="scroll"〉〈mrow〉〈mi〉α〈/mi〉〈/mrow〉〈/math〉 (CTE, in the range of 350 °C (623 K) – 750 °C (1023 K)).〈/p〉 〈p〉It was found, that the same thermal conductivity can be gained by using either a low copper-content composite that features a low degree of deformation or by using a high copper-content composite that was rolled down to a high degree of deformation.〈/p〉 〈p〉Furthermore, we were able to demonstrate that peculiarities in the CTE-over-T curves can be traced back to the plastic deformation of the copper phase, which is affected by rolling-induced residual stresses and recrystallisation processes during the CTE measurement.〈/p〉 〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818339094-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 15 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 775〈/p〉 〈p〉Author(s): Feng Hong, Haiming Cheng, Yan Song, Dan Li, Guixia Liu, Wensheng Yu, Jinxian Wang, Xiangting Dong〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Non-rare-earth red phosphors as alternative to commercial (oxy) nitride phosphors have attracted considerable attention for energy-efficient warm white light-emitting diodes (WLEDs). An excellent narrow-band red emission K〈sub〉2〈/sub〉GeF〈sub〉6〈/sub〉:Mn〈sup〉4+〈/sup〉 product was successfully obtained through co-precipitation method. The crystal structure, morphology, composition and optical properties of K〈sub〉2〈/sub〉GeF〈sub〉6〈/sub〉:Mn〈sup〉4+〈/sup〉 samples were investigated in details 〈em〉via〈/em〉 X-ray powder diffraction (XRD), field emission scanning electron microscope (FESEM), energy dispersive spectrometry (EDS) and photoluminescence spectra, respectively. Mn〈sup〉4+〈/sup〉 activated K〈sub〉2〈/sub〉GeF〈sub〉6〈/sub〉 red phosphor possesses two strong and wide absorption bands in the region of 300–500 nm, which can be applied to UV and blue LED chips and bright intense red light (635 nm) with high color purity. Simultaneously, mechanisms of concentration and temperature quenching were systematically elucidated. After a systematic investigation, the luminescence properties of K〈sub〉2〈/sub〉GeF〈sub〉6〈/sub〉:Mn〈sup〉4+〈/sup〉 have been optimized by changing synthetic conditions, such as the doping concentration, the concentration of HF, the potassium source, the amount of KF and the addition of surfactant. The red phosphor K〈sub〉2〈/sub〉GeF〈sub〉6〈/sub〉:Mn〈sup〉4+〈/sup〉 was packaged 〈em〉via〈/em〉 mixing commercial YAG:Ce yellow phosphor, an outstanding warm WLED with low CCT (3882 K), high CRI (Ra = 90.4) and high luminous efficacy (LE) of 125.84 lm/W has been obtained, implying that K〈sub〉2〈/sub〉GeF〈sub〉6〈/sub〉:Mn〈sup〉4+〈/sup〉 is the potential red phosphor for warm WLEDs.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818331839-fx1.jpg" width="329" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Guozhong Huang, Peipei Zhang, Zhiming Bai〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A novel ZnO nanowire arrays (NAs)/graphene(G)/CdS/electrolyte heterojunction was successfully prepared via a simple three-step synthesis method when applied for photoelectrochemical type self-powered UV–visible photodetectors. Under zero bias, the responsivities of the self-powered UV–visible photodetectors on the basis of ZnO NAs/G/CdS/electrolyte heterojunctions are 27.3 mA/W and 4.3 mA/W for the UV and visible light, respectively, with fast rise and decay times (5 ms). Graphene improves the response of ZnO NAs to UV and visible light to a certain extent owing to its excellent charge-collecting ability and the acceleration of carrier separation and transference. After covering photosensitive CdS nanoparticles, the response to visible light is greatly increased because of the type II energy band structure of ZnO/CdS. It could be inferred from the evidence that the ZnO NAs/G/CdS/electrolyte heterojunction performs effectively in the aspect of self-powered UV–visible detection.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): W. Cui, J. Pan, D.J. Blackwood, Y. Li〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Many previous simulations of the plastic deformation in metallic glasses showed that shear banding is the dominant mode accompanied by Voronoi volume continuous generation and softening. In the present work, we report a contrary phenomenon where Voronoi volume recovery is dominant during plastic deformation in CuZr metallic glasses under tension. By creating a notched geometry, the deformation mode of notched samples transits from shear banding to necking due to the introduction of triaxial stress state. With the suppressing of shear banding, a notch strengthening and structure ordering phenomenon together with the recovery of Cu-centered full-icosahedra fraction are also observed. The present work enriches our understanding on the mechanical behavior and deformation mechanism of metallic glasses.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818339124-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Ting Wang, Ke Han, Qi Tang, Binggang Zhang, Jicai Feng〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Electron beam welding of titanium to copper has been performed with different Cu-V filler metals. Microstructure, mechanical properties and fracture behavior were investigated. Compared with the welded joint without filler metal, the lower V content in Cu75V25 filler metal resulted in the formation of fine Ti-Cu compounds in the interface of TA15 side. Thus, the joint showed a lower tensile strength and fractured along the interfacial reactive layer. When V content is over 34 wt% in the filler metal, the interfacial microstructure near TA15 side formed cellular (Ti,V) solid solution to replace the Ti-Cu compounds, which improved the mechanical properties of the joint. As a result, the joint with Cu66V34 filler metal displayed the highest tensile strength (384 MPa), approaching 82% of that of the copper base metal (BM), and fractured in heat affected zone (HAZ) of copper side, due to the local softening by grains coarsening. In spite of the formed solid solution at the interface, the joint welded with Cu34V66 filler metal containing higher V content, produced amount of pores and unmelted V alloy, which resulted in the decrease of tensile strength down to 55% of that of the copper BM.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818338969-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): M. Bououdina, A.A. Dakhel, A. Jaafar, J.H. Dai, Y. Song〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉This research work aims to study the effect of co-doping by Al〈sup〉3+〈/sup〉 to increase the electronic charge carrier concentration inversely to Mg〈sup〉2+〈/sup〉. Zn〈sub〉0.97〈/sub〉Gd〈sub〉0.03〈/sub〉O, Zn〈sub〉0.95〈/sub〉Gd〈sub〉0.03〈/sub〉Mg〈sub〉0.02〈/sub〉O, and Zn〈sub〉0.95〈/sub〉Gd〈sub〉0.03〈/sub〉Al〈sub〉0.02〈/sub〉O nanopowders were synthesised by simultaneous thermal co-decomposition of a mixture of cadmium and metal complexes, followed by hydrogenation at 350 and 600 °C. This study aimed at establishing the preparation conditions including hydrogenation that were essential for the creation of room temperature ferromagnetic order starting from the paramagnetic Gd-doped ZnO by using structural and electronic consequences of codoping with ions of Al or Mg. X-ray diffraction analysis confirms total doping of (Gd, Mg and Al) impurities into ZnO host lattice as well as the absence of secondary compounds/oxides in the synthesised solid solutions. The reflectance has been found to be significantly affected upon co-doping and hydrogenation, while the energy band gap decreases slightly; i.e. Eg = 3.23–3.00 eV. Magnetic measurements reveal that all the as-synthesised doped ZnO powders gained paramagnetic behaviour defeating the diamagnetic characteristic of ZnO, due to the presence of Gd ions with an effective magnetic moment in the range 8.04–7.12 μ〈sub〉B〈/sub〉. The hydrogenation in the present work conditions did not change the paramagnetic behaviour except for ZnO:Gd:Al-H, showing a partial a magnetic order overlapping with paramagnetic component, resulting in a coercivity of 170.2 Oe, remanence of 0.550 memu/g, and saturation magnetization of 2.14 memu/g. Therefore, the conditions including hydrogenation that were necessary to create FM ordering were determined.〈/p〉 〈p〉First-principles calculations indicate that the Gd doped ZnO systems own large spin polarized effect due to the interaction between Gd-〈em〉f〈/em〉 and O-〈em〉p〈/em〉 electrons. The Mg and Al dopants can modulate the values of magnetic moments.〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Jikang Sun, Wen Zhang, Shiying Wang, Yibin Ren, Qingyun Liu, Yanfang Sun, Lin Tang, Jinxue Guo, Xiao Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Oxygen evolution is the vital and limiting reaction in electrochemical water splitting because of the sluggish kinetics and searching efficient nonprecious metal electrocatalysts is a crucial demand to obtain sustainable and clean fuels. Transition metal borides have recently attracted increasing attention as promising catalysts for oxygen evolution reaction. Herein, ultrathin Ni-Co-B nanosheets have been vertically aligned on reduced graphene oxide as exceptionally efficient oxygen evolution reaction electrocatalyst for the first time. Controlled experiments indicate the critical role of reduced graphene oxide in guiding the formation of Ni-Co-B nanosheet. The catalyst affords a current density of 10 mA cm〈sup〉−2〈/sup〉 at low overpotential of 280 mV, which is better than most of metal boride catalysts reported to date. Stable current output is maintained at 20 mA cm〈sup〉−2〈/sup〉 for at least 60 h. We expect this work will arouse the interests on design of compositing two-dimensional metal borides with graphene, C〈sub〉3〈/sub〉N〈sub〉4〈/sub〉, and metal dichalcogenides towards applications in energy storage and conversion, electrocatalysis, and sensing.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S092583881833977X-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Mikio Fukuhara, Tomoyuki Kuroda, Fumihiko Hasegawa, Yasuyuki Shirai, Toshiyuki Hashida, Kazuya Konno〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Blackish amorphous aluminium oxide film on AlY〈sub〉10〈/sub〉 amorphous alloy ribbons was prepared by anodic polarization process in H〈sub〉2〈/sub〉SO〈sub〉4〈/sub〉 solutions, showing electric storage on uneven surfaces with a convexity of 18 nm in diameter. The longest discharging time was obtained by current ratio (I〈sub〉2〈/sub〉/I〈sub〉1〈/sub〉) of 0.4 at 16 V and 5 mass% H〈sub〉2〈/sub〉SO〈sub〉4〈/sub〉. The discharging time increases and decreases with increasing charging time and charging current, and then saturates after around 100 s and 1 μA, respectively. The resulting film shows a vertical line after Warburg region in a Nyquist diagram, rapid increases in the imaginary impedance, and a phase angle of −90° at 1 mHz in the Bode diagram, demonstrating evidence for use in an electric distributed constant circuit. The film indicates a switching effect for both positive (∼+8.6 eV) and negative (∼-11.2 eV) potentials.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Ping Zhou, Tianli Han, Cuiping Gu, Jinjin Li, Zihan Shen, Huigang Zhang, Junjie Niu, Jinhuai Liu, Jinyun Liu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉High energy density Li-S battery has attracted broad attention; however the capacity retention is still non-ideal. The major challenge is to find a way to effectively prevent the shuttle effect of the lithium polysulfides during charging/discharging. Here, we present a novel wheel-confined composite consisting of MnO〈sub〉2〈/sub〉 nano-rod as wedge and SnO〈sub〉2〈/sub〉 sphere as the skeleton filled with sulfur, which was synthesized using a facile chemical method. The battery with the S@MnO〈sub〉2〈/sub〉@SnO〈sub〉2〈/sub〉 composite as cathode exhibits a capacity as high as 1323 mAh g〈sup〉−1〈/sup〉 at 0.1 C and a high capacity retention of only 0.03% decay per cycle over 500 cycles, which indicates a greatly reduced shuttle effect in Li-S batteries. The battery also shows good rate-performance and low-temperature properties. In addition, the I-V measurements and the first-principle calculations have demonstrated an enhanced electron transfer through the composite.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818338465-fx1.jpg" width="279" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Shiqiang Yue, Hua Zhang, Rijin Cheng, Anding Wang, Yaqiang Dong, Aina He, Hongwei Ni, Chain-Tsuan Liu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Magnetic and thermal stabilities of Fe-based amorphous alloys with high saturation flux density (〈em〉B〈/em〉〈sub〉s〈/sub〉) are important for the application and understanding of the atomic interaction. Fe〈sub〉〈em〉x〈/em〉〈/sub〉(Si〈sub〉3〈/sub〉B〈sub〉13〈/sub〉)〈sub〉(100-x)/16〈/sub〉 (〈em〉x〈/em〉 = 86-71) eutectic amorphous alloys with superior manufacturability and Fe content limit were developed and the compositional effects were investigated. The alloys exhibit high 〈em〉B〈/em〉〈sub〉s〈/sub〉 of 1.53–1.68 T, low coercivity of 2.2–4.3 A/m, and high permeability of 8.8–12.8 × 10〈sup〉3〈/sup〉. With the increase of Fe content, it is found that the 〈em〉B〈/em〉〈sub〉s〈/sub〉 have an inflection point, the crystallization and Curie temperatures decrease drastically. The high Fe content alloys exhibit reduced thermal stabilities of magnetic properties, because the enhanced magnetic intercoupling effect is much lower than the weakened atomic bonding. For the alloys with 〈em〉x〈/em〉 = 71–74, the decline rate of 〈em〉B〈/em〉〈sub〉s〈/sub〉 is still lower than 10% at the extreme condition of 200 °C, while 〈em〉B〈/em〉〈sub〉s〈/sub〉 of the alloy with 〈em〉x〈/em〉 = 84 decreases more than 10% at 120 °C. The thermal stability of magnetic properties should be taken into consideration for the devices used in unique condition, especially for the high 〈em〉B〈/em〉〈sub〉s〈/sub〉 amorphous alloys.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Milivoj Plodinec, Ivana Grčić, Marc G. Willinger, Adnan Hammud, Xing Huang, Ivana Panžić, Andreja Gajović〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Novel forms of black TiO〈sub〉2〈/sub〉 nanotubes-based photocatalysts for water purification were prepared. Two features were combined: decoration of TiO〈sub〉2〈/sub〉 nanotube arrays with Ag nanoparticles (sample TiO〈sub〉2〈/sub〉-NT's@Ag) and further hydrogenation of this material (TiO〈sub〉2〈/sub〉-NT's@Ag-HA). Obtained photocatalysts show high efficiency for degradation of salicylic acid, a typical water-borne pollutant. The photocatalysts considerably exceed the photocatalytic properties of TiO〈sub〉2〈/sub〉 nanotubes and commercial TiO〈sub〉2〈/sub〉 P25 taken as a reference for modeling of the photocatalytic process. The comparison of photocatalytic activities between novel photocatalyst was based on a numerical approach supported by the complex kinetic model. This model allowed a separate study of different contributions on overall degradation rate. The contributions include: salicylic acid photolysis, photocatalysis in UVB, UVA and in the visible part of applied simulated solar irradiation. The superior photocatalytic performance of the photocatalyst TiO〈sub〉2〈/sub〉-NT's@Ag-HA, particularly under visible irradiation, was explained by the combined effect of a local surface plasmon resonance (LSPR) due to Ag nanoparticles and creation of additional energy levels in band-gap of TiO〈sub〉2〈/sub〉 due to Ti〈sup〉3+〈/sup〉 states at nanotube surfaces. The presence of Ag also positively influence charge separation of created electron-holes pairs. The synergy of several effects was quantified by a complex kinetic model through the factor of synergy, 〈em〉f〈/em〉〈sub〉Syn〈/sub〉. Stability testing indicated that the catalysts were stable for at least 20 h. The novel design of catalysts, attached on Ti foils, presents a solid base for the development of more efficient photocatalytic reactors for large-scale with a long-term activity.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818339197-fx1.jpg" width="381" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Jian Wang, Yangyang Yin, Hongxia Jin, Jianwen Zhang, Yan Li, Chengwei Wang, Moyi Duan〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The composite structures of tightly embedding the rare-earth oxide La〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 nanoparticles into TiO〈sub〉2〈/sub〉 film are designed and have been successfully prepared by using the sol-gel and spin-coating method. Appearance of a large amount of nano-cracks on the La〈sub〉2〈/sub〉O〈sub〉3〈/sub〉@TiO〈sub〉2〈/sub〉 composite film surface supplies a textured surface to study the effect of nanostructured surface on the electrowetting on dielectric (EWOD) performance. The characterizations of chemical composition and crystal phase structure indicate the La〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 nanoparticles with polycrystalline nature have been grown and distribute uniformly in TiO〈sub〉2〈/sub〉 film. Valuably, plenty of intimate contact heterogeneous La〈sub〉2〈/sub〉O〈sub〉3〈/sub〉/TiO〈sub〉2〈/sub〉 interfaces are formed, and supply an ideal space for charge accumulation and electric energy storage. All data of EWOD response test show the applied superlow voltage can induce a large contact angle (CA) change, but the breakdown voltage is still high. The EWOD response does not agree with the well-known Young-Lippmann equation, especially obvious in low voltage range. Moreover, the optimal parameters of layer number of 8 and La〈sup〉3+〈/sup〉 doping concentration of 0.9% are obtained to enhance EWOD response for superlow applied voltage and the lower saturation CA. Detailed investigations and analysis reveal that the electric absorption has important roles on EWOD response under superlow applied voltage for the nanostructured surface. Furtherly, the space charge polarization theory is proposed to illustrate the enhancement of EWOD performance. When the voltage is applied, plenty of charges would be accumulated on the heterogeneous La〈sub〉2〈/sub〉O〈sub〉3〈/sub〉/TiO〈sub〉2〈/sub〉 interfaces and the space charge polarization is formed, this significantly heightens polarizability of the La〈sub〉2〈/sub〉O〈sub〉3〈/sub〉@TiO〈sub〉2〈/sub〉 composite film, and further increases their effective dielectric constant and improves EWOD performance. But the electric absorption of water on the nanostructured surface causes the inconsistency of EWOD response with the tested and calculated capacitance. The present study shows a new insight to design and fabricate structured dielectric for the solution of EWOD difficulties.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Federico J. Pomiro, Juan P. Gaviría, Gastón G. Fouga, Leonardo D. Vega, Ana E. Bohé〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The reactions of Pr〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 and Pr〈sub〉6〈/sub〉O〈sub〉11〈/sub〉 with Cl〈sub〉2〈/sub〉(g) were studied thermodynamically and experimentally, and proposed in the systems Pr〈sub〉2〈/sub〉O〈sub〉3〈/sub〉/Cl〈sub〉2〈/sub〉(g) and Pr〈sub〉6〈/sub〉O〈sub〉11〈/sub〉/Cl〈sub〉2〈/sub〉(g). A kinetic analysis was performed on Pr〈sub〉6〈/sub〉O〈sub〉11〈/sub〉 chlorination, which differs from with other light rare earth oxide chlorinations. The praseodymium oxychlorides obtained by full chlorination of Pr〈sub〉6〈/sub〉O〈sub〉11〈/sub〉 at 425 °C and 800 °C are different, being well characterized by X-ray diffraction, scanning electron microscopy, magnetic susceptibility measurements and X-ray photoelectron spectroscopy. The crystal structures of the oxychlorides were refined with the Rietveld method. The comparison between the theoretical magnetic moment of Pr〈sup〉3+〈/sup〉 and the estimated magnetic moment in the praseodymium oxychloride obtained at 425 °C revealed the presence of Pr〈sup〉3+〈/sup〉 and Pr〈sup〉4+〈/sup〉, whereas no significant difference was observed between the theoretical and the experimental values of Pr〈sup〉3+〈/sup〉 obtained for the praseodymium oxychloride prepared at 800 °C. These observations are consistent with the analyses in the X-ray photoelectron spectra for both oxychlorides. Finally, a general formula of PrO〈sub〉1+x〈/sub〉Cl is proposed for the oxychlorides synthesized at T 〈 800 °C.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Guang Chen, Jun Wang, Hongyuan Fan, Danqi Wang, Xiaoying Li, Hanshan Dong〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Possibility of improving the resistance of AISI H13 steel to molten aluminum corrosion by liquid nitrocarburizing (LNC) was explored. The effects of the LNC parameters in terms of temperatures (703/723/743 K) and soaking time (4/8/12 h) on phase transformation, microstructure, and resistance to molten aluminum were fully studied. The surface phase compositions and the cross-sectional phase distribution of the LNC treated specimens were studied by implementable X-ray diffraction analysis. Microstructure, element distribution, microhardness, and the kinetics of the nitrocarburized case formation were fully researched. Immersion test of corrosion resistance to molten aluminum was carried out at 1023 K for 30min. It is observed that an oxide layer can be produced on the top of the nitrocarburized case during LNC treatment, which cannot be regularly produced by other nitriding methods. The nitrocarburized case consists of a compound layer, a diffusion layer, and a transition layer. The growth of the nitrocarburized case is proportional to the squared treatment time and follows the Arrhenius law for the treatment temperature. The activation energy is estimated to be 195.4 kJ mol〈sup〉−1〈/sup〉. While the nitrocarburized case provided limited resistance to molten aluminum, the oxide layer formed on the top of the nitrocarburized case conferred significantly improved molten aluminum corrosion resistance, especially a duplex oxide layer produced at 743 K.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Z. Mroczek, A. Morawski, T. Czujko, F. Karaboğa, M. Akdoğan, A.J. Zaleski, M. Małecka, T. Cetner, H. Yetiş, D. Gajda, I. Belenli〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this article, the significant impact of a lamellar (layered) structure and a high isostatic pressure on the normal state resistance (〈em〉R〈/em〉〈sub〉n〈/sub〉), critical temperature (〈em〉T〈/em〉〈sub〉c〈/sub〉), irreversible magnetic field (〈em〉B〈/em〉〈sub〉irr〈/sub〉), upper magnetic field (〈em〉B〈/em〉〈sub〉c2〈/sub〉) and critical current densities (〈em〉J〈/em〉〈sub〉c〈/sub〉) at 4.2 K and 20 K was presented. Our research showed that annealing at temperatures in the range of 630 °C–680 °C (above the melting point of Mg) at atmospheric pressure (0.1 MPa) did not create a lamellar (layered) structure. This led to low 〈em〉T〈/em〉〈sub〉c〈/sub〉, 〈em〉J〈/em〉〈sub〉c〈/sub〉 and 〈em〉B〈/em〉〈sub〉irr〈/sub〉 and high 〈em〉R〈/em〉〈sub〉n〈/sub〉. The analysis, made by using scanning electron microscopy (SEM), showed that the annealing temperature increased up to 700 °C under a pressure of 0.1 MPa, which created a lamellar structure. This led to significant growth of 〈em〉T〈/em〉〈sub〉c〈/sub〉, 〈em〉J〈/em〉〈sub〉c〈/sub〉 and 〈em〉B〈/em〉〈sub〉irr〈/sub〉 and a slight increase of 〈em〉R〈/em〉〈sub〉n〈/sub〉. Moreover, the measurements showed that annealing at temperatures from 630 °C to 700 °C did not change the 〈em〉B〈/em〉〈sub〉c2〈/sub〉 value. In comparison to pressureless heat treatment, annealing under the high isostatic pressure of 1.1 GPa obtained a lamellar structure with layers of lower thickness and higher density. This led to significant increases in 〈em〉J〈/em〉〈sub〉c〈/sub〉 and 〈em〉B〈/em〉〈sub〉irr〈/sub〉 and a visible reduction of 〈em〉R〈/em〉〈sub〉n〈/sub〉. SEM analysis showed that the increase of isostatic pressure up to 0.3 GPa created a lamellar structure with thicker layers and lower density. This microstructure led to lower 〈em〉J〈/em〉〈sub〉c〈/sub〉 and 〈em〉B〈/em〉〈sub〉irr〈/sub〉 and significantly higher 〈em〉R〈/em〉〈sub〉n〈/sub〉. On the other hand, the SEM analysis showed that annealing under 0.8 GPa did not cause the formation of a layered structure, and as a result, it led to significant reductions in 〈em〉B〈/em〉〈sub〉irr〈/sub〉 and 〈em〉J〈/em〉〈sub〉c〈/sub〉 (4.2 K and 20 K) and higher 〈em〉R〈/em〉〈sub〉n〈/sub〉. The increase of the isostatic pressure from 0.1 MPa to 1.1 GPa did not affect 〈em〉T〈/em〉〈sub〉c〈/sub〉 (〈em〉B〈/em〉 = 0 T) and 〈em〉B〈/em〉〈sub〉c2〈/sub〉. The results indicated that the layered structure obtained a high density of pinning centers, which were particularly effective at higher magnetic fields. 〈em〉J〈/em〉〈sub〉c〈/sub〉 of 100 A/mm〈sup〉2〈/sup〉 in 8 T at 4.2 K was obtained in 〈em〉in situ〈/em〉 undoped MgB〈sub〉2〈/sub〉 wires after annealing at 700 °C for 40 min under an isostatic pressure of 1.1 GPa.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818339434-fx1.jpg" width="267" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Si-Ming Zeng, Xin-Gui Tang, Qiu-Xiang Liu, Yan-Ping Jiang, Ming-Ding Li, Wen-Hua Li, Zhen-Hua Tang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉BaCe〈sub〉x〈/sub〉Ti〈sub〉1−x〈/sub〉O〈sub〉3〈/sub〉 (BCT) ceramics at x = 0.025, 0.05, 0.075 and 0.1 were prepared by the traditional solid state reaction route and sintered at 1540 °C for 6 h. The microstructural, dielectric, electrocaloric, and pyroelectric performances of BCT were systematically explored. Hysteresis loops were measured under various temperatures, and the electrocaloric effect (ECE) was calculated for all samples. The results showed that BaCe〈sub〉0.075〈/sub〉T〈sub〉0.925〈/sub〉O〈sub〉3〈/sub〉 had the best ECE which exhibited a large adiabatic temperature change of 0.81 K, an isothermal entropy change of 0.82 JK〈sup〉−1〈/sup〉kg〈sup〉−1〈/sup〉 and an electrocaloric strength of ∼0.28 Km/MV. Further, the pyroelectric figure of merits (FOMs) were analyzed and the results indicated that BaCe〈sub〉0.1〈/sub〉T〈sub〉0.9〈/sub〉O〈sub〉3〈/sub〉 would be a better candidate for pyroelectric devices which exhibited high pyroelectric coefficient (p) of 7.82 × 10〈sup〉−4〈/sup〉〈em〉Cm〈/em〉〈sup〉−2〈/sup〉K〈sup〉−1〈/sup〉 and FOM of high detectivity (F〈sub〉d〈/sub〉) of 10.39 μPa〈sup〉−1/2〈/sup〉. These results in this work would facilitated the development of the electrocaloric and pyroelectric performance of Ce-doped BaTiO〈sub〉3〈/sub〉 ceramics.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Baishun Li, Kai Guan, Qiang Yang, Xiaodong Niu, Dongdong Zhang, Shuhui Lv, Fanzhi Meng, Yuanding Huang, Norbert Hort, Jian Meng〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Microstructures and mechanical properties of a Mg−8Gd−3Yb−1.2Zn−0.5Zr (wt%) alloy have been investigated. The dominant intermetallic phases in the as-cast sample are Mg〈sub〉5〈/sub〉RE (RE = Gd,Yb) phase, 14H-type long-period stacking ordered (LPSO) phase, and Mg〈sub〉2〈/sub〉Zn〈sub〉2〈/sub〉RE (W) phase and ordered Mg〈sub〉12〈/sub〉RE phase. Furthermore, the ordered Mg〈sub〉12〈/sub〉RE phase generally coexists with the W phase following an orientation relationship as [0〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.gif" overflow="scroll"〉〈mrow〉〈mover accent="true"〉〈mn〉1〈/mn〉〈mo〉¯〈/mo〉〈/mover〉〈/mrow〉〈/math〉1]〈sub〉w〈/sub〉//[〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si2.gif" overflow="scroll"〉〈mrow〉〈mover accent="true"〉〈mn〉2〈/mn〉〈mo〉¯〈/mo〉〈/mover〉〈/mrow〉〈/math〉30]〈sub〉Mg12RE〈/sub〉, and (〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.gif" overflow="scroll"〉〈mrow〉〈mover accent="true"〉〈mn〉1〈/mn〉〈mo〉¯〈/mo〉〈/mover〉〈/mrow〉〈/math〉11)〈sub〉w〈/sub〉//(001)〈sub〉Mg12RE〈/sub〉. After extrusion, the microstructure is consisted of un-recrystallized regions along with a small part of fine dynamically recrystallized (DRXed) regions. Simultaneously, the coarse Mg〈sub〉5〈/sub〉RE, W and Mg〈sub〉12〈/sub〉RE particles were disintegrated and mainly distribute at extrusion stringers while the fine LPSO plates mainly distribute in un-recrystallized regions. Moreover, amounts of nanoscale Mg〈sub〉5〈/sub〉RE particles were dynamically precipitated in DXRed regions. Then, the as-extruded Mg−8Gd−3Yb−1.2Zn−0.5Zr alloy exhibits clearly higher strength than the classic rare-earth-containing magnesium alloys with comparative or even much higher rare earth content at both room temperature and high temperatures. The dominant strengthening mechanism was finally revealed as precipitation/dispersion strengthening.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): An-Nan Chen, Meng Li, Jia-Min Wu, Li-Jin Cheng, Rong-Zhen Liu, Yu-Sheng Shi, Chen-Hui Li〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Highly porous mullite ceramics with bimodal pore structures were fabricated by selective laser sintering (SLS), in which the closed pores were provided by core-shell structure of fly ash hollow spheres (FAHSs) and the open pore channels were created by spherical polyamides (PA12). With increasing sintering temperature, the total porosity of mullite ceramics decreased, in which the average closed pore size reduced and the average open pore size distribution kept constant, however, the compressive strength of ceramic foams increased. This strength enhancement was mainly attributed to the reinforced sintering necks between FAHSs when sintered below 1350 °C, which resulted from the liquid phase diffusion of K, Ca and Ti, while the densification and thickening of sphere shell walls played a key role when above 1350 °C. Our findings illustrate that understanding pore structure characteristics and strength enhancement mechanism changes will be helpful for designing highly porous mullite ceramics with high mechanical performance.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818340362-fx1.jpg" width="281" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Ting Zhang, Lehua Qi, Jiawei Fu, Jiming Zhou, Xujiang Chao〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In the present study, carbon fibers grafted with SiC nanowires (C〈sub〉f〈/sub〉-SiCNWs) reinforced AZ91D composite (C〈sub〉f〈/sub〉-SiCNWs/AZ91D) was prepared by liquid-solid extrusion following vacuum infiltration (LSEVI) process. The effect of SiC nanowires (SiCNWs) on the interfacial microstructure, tensile properties and fracture behavior of the C〈sub〉f〈/sub〉-SiCNWs/AZ91D composite were investigated. First, the microstructure and fracture surface of the composite were characterized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The results showed that after introducing SiCNWs, the antioxidation of carbon fiber could be reasonably improved, which provided a better interface of the C〈sub〉f〈/sub〉-SiCNWs/AZ91D composite by preventing the detrimental interfacial reaction product of Al〈sub〉4〈/sub〉C〈sub〉3〈/sub〉. Then, the average ultimate tensile strength of SiCNWs-C〈sub〉f〈/sub〉/AZ91D composite was compared with that of C〈sub〉f〈/sub〉/AZ91D composite. It was found that after grafting SiCNWs on the surface of carbon fibers, the strength increased from 269.7 MPa to 358.8 MPa, corresponding to an improvement of 33%. This increase was attributed to the improved interface that took advantages of the superior mechanical properties of SiCNWs.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Viney Dixit, Jacques Huot〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉In this paper we report the effect of Ti-proportion and addition of Zr-Ni on the crystal structure, morphology and hydrogen storage kinetics of Ti-V-Cr alloy. For this study, five alloys of compositions Ti〈sub〉x〈/sub〉V〈sub〉70-x〈/sub〉Cr〈sub〉30〈/sub〉 (x = 10, 20, 30, 40, 50) added with 4 wt% of 7Zr+10Ni were synthesized. Scanning electron microscopy revealed that all alloys were multiphase. X-ray powder diffraction confirmed that all the as-cast alloys have the body-centred cubic (bcc) phase as the main phase. The same amount of (7Zr+10Ni) was added in all of the alloys, but each alloy has shown a different elemental concentration in their secondary phases. For alloys x = 10 and 20, a Zr rich secondary phase was formed but for alloys x = 30, 40 and 50, the secondary phase has relatively high concentration of all elements.〈/p〉 〈p〉Upon hydrogenation, the bcc phase transformed into a face-centred cubic (fcc) phase. For x = 20, 30 and 40 a body-centred tetragonal (bct) phase was also observed along with fcc phase. Hydrogenation kinetics of all of these alloys was measured and it was found that absorption capacity increased with Ti-content. The maximum absorption capacity of 3.6 wt% was achieved for x = 50.〈/p〉 〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818339574-fx1.jpg" width="256" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Alloys and Compounds, Volume 776〈/p〉 〈p〉Author(s): Yu-Hua Wen, Li-Hong Zhang, Jin-Bo Wang, Rao Huang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Pt〈sub〉3〈/sub〉Co nanoparticles are promising catalyst candidates for fuel-cell applications because their catalytic performances are superior to pure Pt nanoparticles. Fundamental insights into the thermostability of Pt〈sub〉3〈/sub〉Co nanoparticles are critical for their syntheses, post-treatments, and ultimate applications. In this article, the thermal stability of Pt〈sub〉3〈/sub〉Co nanoparticles has been investigated by molecular dynamics simulations. Two types of structures, chemically disordered alloy and ordered intermetallic compound, are considered. Besides, two-atomic-layered Pt and Co have been introduced to coat the Pt〈sub〉3〈/sub〉Co nanoparticles to form Pt〈sub〉3〈/sub〉Co-Pt and Pt〈sub〉3〈/sub〉Co-Co core-shell nanoparticles. The simulated results reveal that the ordered intermetallic Pt〈sub〉3〈/sub〉Co nanoparticles exhibit better thermal stability than the disordered alloy ones. Pt coating is greatly superior to Co coating for improving both structural and thermal stability of Pt〈sub〉3〈/sub〉Co nanoparticles. For Pt〈sub〉3〈/sub〉Co and Pt coated Pt〈sub〉3〈/sub〉Co nanoparticles, the overall melting simultaneously happens in both Pt and Co. However, Co-coated surface induces the two-stage melting of Pt〈sub〉3〈/sub〉Co nanoparticles at large sizes; it markedly decreases the thermal stability of the nanoparticles at small sizes, resulting in the melting point even lower than pure Co ones. The remarkably lowered melting temperature is associated with the order-to-disorder transformation in the Co-coated shell and the appreciable change of particle shape before surface premelting.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0925838818339495-fx1.jpg" width="257" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 20 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 559〈/p〉 〈p〉Author(s): Rahul Saha, Ramgopal V.S Uppaluri, Pankaj Tiwari〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Experimental investigations targeting optimum chemical slug formulations for tertiary enhance oil recovery of heavy crude oil in carbonate reservoir were carried out. Based on interfacial tension (IFT), emulsification, wettability alteration and core flooding studies, two alkalis and eight surfactants have been screened by considering conditions similar to oil reservoirs (0–20% salinity and 30–80 °C temperature). Dynamic IFT studies interestingly affirmed oil-layer break time phenomena and hence enhanced emulsification extent. Alkali, thermally stable surfactant mixture and alkali-surfactant mixture systems reduced IFT to 10〈sup〉−1〈/sup〉, 10〈sup〉−2〈/sup〉 and 10〈sup〉−3〈/sup〉 mN/m respectively. Flooding studied confirmed an additional oil recovery of 12.79% and 14.46% for alkali and alkali-surfactant mixture systems respectively. On the other hand, due to optimal emulsion stability, maximal residual oil recovery of 24.58% being achieved for a slug formulation of 0.1 wt% surfactant mixture. Surfactant concentration above 0.1 wt% enabled stronger emulsion formation that detriments displacement efficiency and oil recovery factor.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718311178-ga1.jpg" width="341" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 20 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 559〈/p〉 〈p〉Author(s): Mi Zhang, Jilai Gong, Guangming Zeng, Peng Zhang, Biao Song, Weicheng Cao, Hongyu Liu, Shuangyan Huan〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉As a photocatalyst, bismuth vanadate coupled with reduced oxide graphene (BiVO〈sub〉4〈/sub〉-rGO) has been reported for dye degradation. However, this catalyst faced the disadvantages of low catalytic efficiency and long catalytic time. In this paper, BiVO〈sub〉4〈/sub〉-rGO composites were synthesized by a modified hydrothermal method, and characterization results showed the monoclinic BiVO〈sub〉4〈/sub〉 surface successfully coupled with a layer of rGO. The dye removal performance of BiVO〈sub〉4〈/sub〉-rGO composites were evaluated by the degradation of malachite green and rhodamine B under visible light irradiation and photocatalytic results showed that the BiVO〈sub〉4〈/sub〉 with rGO modification could effectively enhance the dyes removal performance. In a specific photocatalytic experiment, BiVO〈sub〉4〈/sub〉-rGO-300 could remove 99.5% MG in two hours and 99.84% RhB in four hours, which was superior to previous studies. Furthermore, application of catalyst in practical wastewater was also taken into account. MG and RhB were degraded by BiVO〈sub〉4〈/sub〉-rGO in several kinds of actual wastewater and experimental results showed that this catalyst could efficiently remove dye in actual environment. This improvement could be ascribed to the increase of special surface area, efficient charge transfer and reduction of electron-hole pair recombination with the incorporation of rGO. The influences of pH, supporting electrolyte and mechanism of the dye degradation were also investigated in details.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉 〈p〉The dyes removal performance for MG and RhB was effectively enhanced and the catalyst has a good potential in dye wastewater treatment.〈/p〉 〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S092777571831135X-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉 〈/div〉

Description: 〈p〉Publication date: 20 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 559〈/p〉 〈p〉Author(s): Min Jae Shin, Young Jae Shin, Jae Sup Shin〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this study, the molecular imprinting technique and self-assembled monolayer technique were combined to increase the recognition ability of cholesterol. A self-assembled monolayer with 4-mercaptophenol and benzenethiol was formed on a gold plate, and the reaction of cholesteryl chloroformate with the phenol group in the 4-mercaptophenol was followed. This layer was then coated with poly(methyl methacrylate) (PMMA). In order to expose the cholesterol buried under the coating, the partial upper part of the coated PMMA was then removed by stroking the coated plate in acetone solvent. The molecular imprinted site was prepared by hydrolysis of the carbonate bond and extraction of the hydrolyzed cholesterol. This gold plate was used as a working electrode to test the recognition ability for cholesterol. The result showed that the plate obtained good recognition ability for cholesterol compared with cholic acid. The ratio of 4-mercaptophenol to benzenethiol was a very important factor in the ability to recognize cholesterol. Regulating the thickness of the coated PMMA was also one of the important factors to increase the ability to recognize cholesterol.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S092777571831238X-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 560〈/p〉 〈p〉Author(s): Nichaphat Thongsai, Nattapong Tanawannapong, Janjira Praneerad, Sumana Kladsomboon, Panichakorn Jaiyong, Peerasak Paoprasert〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Rice husk, an agricultural waste that currently finds few uses, is rich in cellulose-based materials and silica. In this work, a simple one-pot method for preparing carbon dots and mesoporous silica from rice husk was developed, using hydrothermal and calcination methods. The carbon dots exhibited blue emission with excellent photostability, and had a diameter of 4–5 nm and a quantum yield of 3%. They were demonstrated to be capable of detecting alcohol vapors at room temperature, and of distinguishing between methanol, ethanol, and several volatile organic compounds when used as the sensing layer in an optical electronic nose system. The alcohol content of a commercial beverage was successfully determined using the carbon dot-integrated electronic nose. The solvation effect of the alcohol vapors on the electronic absorption spectra of model carbon dot structures was illustrated using time-dependent density functional theory with the dielectric polarizable continuum model. The UV–vis and computational results confirmed that the sensing mechanism of carbon dots is through the modulation of their optical absorbance governed by polar-polar interfacial interactions. This was experimental and computational demonstration of carbon dot sensing of vapors. Their excellent biocompatibility suggests biomedical applications, in addition to sensing. The production of two functional materials from a single low-value waste source was demonstrated.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718312378-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 560〈/p〉 〈p〉Author(s): Chenhao Zhao, Zhibiao Hu, Jiangshui Luo〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Porous carbon box or nanoplate has been prepared by synchronous carbonization/activation of potassium citrate, and the corresponding porous carbon nanoplate/Se composite can be obtained using a melting-diffusion method. The influence of structure parameters including specific surface area and porous structure of porous carbon and resultant carbon/Se composite on electrochemical properties are studied. It is found a moderate micropore size of carbon substrate and low specific surface area of carbon/Se composite are benefit to electrochemical performances. At an optimal temperature of 700 °C, the porous carbon composed of micro- and small meso-porous (2–4 nm) structure has a BET specific surface area of 695.4 m〈sup〉2〈/sup〉 g〈sup〉−1〈/sup〉, and the amorphous Se is uniformly encapsulated into its porous structure. As the cathode material of Li ion battery, the porous carbon nanoplate/Se composite delivers an initial discharge capacity of 589.2 mAh g〈sup〉−1〈/sup〉 with Coulombic efficiency of 72.6% at 0.2C, and capacity retention of 78.3% can be obtained after 500 cycles at 2C. Even at a high rate of 4C, a discharge capacity of 415.2 mAh g〈sup〉−1〈/sup〉 can be reached.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718312950-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 560〈/p〉 〈p〉Author(s): Ting Zou, You Han, Xinxue Li, Wei Li, Jinli Zhang, Yan Fu〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Controlled synthesis of noble metal nanocatalysts with desirable catalytic activities remains a great challenge. Inspired by electron-rich functional groups and supramolecular assembly properties of natural nucleotides, herein we propose a versatile approach to construct Pd nanocatalysts through employing seven nucleotides as both electron donors and stabilizers. The catalytic performance of nucleotide-Pd complexes are greatly associated with the chemical structures of nucleobases as well as the number of phosphate groups. Guanosine 5′-triphosphate-Pd complexes possess high activities in the hydrogenation reduction of 4-nitrophenol assisted by NaBH〈sub〉4〈/sub〉, with the relative rate constant of 7770 min〈sup〉−1〈/sup〉 mM〈sup〉−1〈/sup〉 at 25 °C. Pd(II)-coordinated nucleotides are also promising in NaBH〈sub〉4〈/sub〉-mediated degradation of organic dyes. This work demonstrates a green and facile process to construct Pd nanocatalysts containing abundant active sites under the assistance by natural nucleotides.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718314377-ga1.jpg" width="471" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 20 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 559〈/p〉 〈p〉Author(s): Mirela Teodorescu, Maria Bercea, Simona Morariu〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The present study has been focused on investigation of some polymer mixtures of interest for biomedical applications. Three pairs of polymers, namely: poly(vinyl alcohol) (PVA)/poly(vinylpyrrolidone) (PVP), PVA/hydroxypropyl cellulose (HPC), Pluronic F127 (PL)/HPC were subjected to viscometic study in dilute solution. The intrinsic viscosity, the Huggins constant and 〈em〉B〈/em〉 parameter, as well as the miscibility parameters were discussed. The hydrodynamic properties of these polymer mixtures were analyzed as compared with the corresponding single polymer solutions at two reference temperatures, 〈em〉i.e.〈/em〉 the storage (25 °C) and physiological (37 °C) temperature. Each mixture has shown distinct behavior: PVA/PVP system is fully miscible regardless composition or temperature; the miscibility of PVA/HPC or PL/HPC mixtures is influenced in a specific manner by the ratio between the two polymers and by the temperature. The main interest is a better understanding of the polymer-polymer interactions and to identify the synergistic behavior in order to design multicomponent biomaterials with targeted properties. The compatibility of these polymers was attributed to the favorable hydrogen-bonding interactions between the hydroxyl groups of PVA and carbonyl groups of PVP, hydroxyl groups of PVA and HPC, and ether groups of PL and hydroxyl groups of HPC. On the other hand, hydrophobic interactions influence the polymer/polymer miscibility.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718311749-ga1.jpg" width="225" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 20 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 559〈/p〉 〈p〉Author(s): Xiaopeng Xue, Zhonghao Xu, Israel Pedruzzi, Ping Li, Jianguo Yu〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Interface phenomena between low molecular weight (LMW) carboxylic acids and muscovite was investigated through molecular dynamic simulation and experiment, where the typical monocarboxylic acids including formic acid (C〈sub〉1〈/sub〉), acetic acid (C〈sub〉2〈/sub〉), propionic acid (C〈sub〉3〈/sub〉) and butyric acid (C〈sub〉4〈/sub〉) were used as models. Density distribution, adsorption energy, root mean square dynamic (RMSD) of carboxylic acids on water-muscovite interface were calculated through molecular dynamic simulation, and the advanced characterization methods, such as ATR-FTIR spectra, AFM images and contact angle were performed to test and verify the relative simulation findings. The molecular simulation showed that carboxylic acids adsorbed on surface of muscovite through hydrogen bond between H atom of 〈img src="https://sdfestaticassets-us-east-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉COOH functional group of carboxylic acid and O atom of muscovite, belong to outer sphere adsorption, and ATR-FTIR spectra and AFM images confirmed this finding. Adsorption energy for long carbon chain carboxylic acid (C〈sub〉4〈/sub〉) was higher than that for short carbon chain carboxylic acid (C〈sub〉1〈/sub〉, C〈sub〉2〈/sub〉 and C〈sub〉3〈/sub〉) due to the effect of carboxylic acid diffusion on water-muscovite interface. The hydrophilic functional group 〈img src="https://sdfestaticassets-us-east-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉COOH of carboxylic acids preferably adsorbed on muscovite surface, while the hydrophobic functional groups 〈img src="https://sdfestaticassets-us-east-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉CH〈sub〉3〈/sub〉 and 〈img src="https://sdfestaticassets-us-east-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉CH〈sub〉2〈/sub〉 of carboxylic acids were far from the muscovite surface. So, the hydrophobicity on muscovite surface increased due to the adsorption of carboxylic acids, which resulted in the increase of contact angle of water on muscovite surface.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718310823-ga1.jpg" width="242" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 560〈/p〉 〈p〉Author(s): Guowen Chen, Yuying Fu, Fuge Niu, Hao Zhang, Xiaomeng Li, Xin Li〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉To evaluate the performance of biopolymer fabricated nanoparticle under commercial processing conditions, the stability of gum Arabic (GA)-zein-cur (curcumin) colloidal system was recorded and analyzed. The results showed that GA-zein-cur system is colloidal stable in the pH range of 5–8, however, encapsulated curcumin degraded rapidly as long as the pH changes. As for processing temperature, more than 70 °C will affect the spatial structure of zein and leading to the leak or exposure of encapsulated curcumin which result in the degradation of curcumin. Na〈sup〉+〈/sup〉 has no significant effect on colloidal and chemical performance of nanoparticles while Fe〈sup〉3+〈/sup〉 could penetrate the zein nanosphere and compromise curcumin. Results of our work imply that the protein-based core-shell delivery system has advantages in solubilizing the hydrophobic compounds and has certain ability to protect the encapsulated material against the unfavorable environment.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718308707-ga1.jpg" width="313" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 560〈/p〉 〈p〉Author(s): Haiqin Wu, Liang Yan, Liyang Fu, Lan Jin〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The interaction of alizarin with aminophenylboronic acid (ARS-PBA) was used through a new strategy for electrochemical sensors of glucose. In the present work, ARS-PBA complex and the layered double hydroxide nanosheets (LDH nanosheets) were successfully assembled on indium tin oxide (ITO) electrodes via layer by layer technology method. The resulted electrode was characterized by UV–vis, X-ray diffraction (XRD), atomic force microscope (AFM) and scanning electron microscope (SEM) to achieve the morphological, structural and compositional information. Cyclic voltammetry and differential pulse voltammetry were conducted to investigate electrochemical properties of the modified electrode. Moreover, the modified electrode was used as a non-enzymatic sensor for glucose determination, exhibiting good electrochemical properties, fast response time and long-term stability. At the optimum conditions, the constructed electrode sensor shows a linear range of 0∼1.00 μmol/L and a low detection limit of 4.0 nmol/L (S/N = 3) for glucose. On the basis of affinity between glucose and ARS-PBA complex, the functionalized electrode showed a high selectivity toward glucose over other concomitant biomolecues (dopamine, uric acid and ascorbic acid). Therefore, a simple and effective electrochemical method was developed and offers a complementary tool for the detection of glucose.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718313219-ga1.jpg" width="358" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 20 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 559〈/p〉 〈p〉Author(s): Priyadharsan A., Shanavas S., Vasanthakumar V., Balamuralikrishnan B., Anbarasan P.M.〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The sunlight driven photocatalytic activity of semiconductor based nanocomposites has attracted extensive attention in recent years for environmental remediation and energy applications. Here, we report an effective strategy to synthesis ternary MoS〈sub〉2〈/sub〉-ZnO-reduced graphene oxide (MZG) nanocomposite as a photocatalyst by a facile hydrothermal method. The prepared nanoparticles were characterized by various analytical tools. The basic photocatalytic mechanism of the composite material was exhibited the photoexcited electrons of ZnO can be readily transported to MoS〈sub〉2〈/sub〉 through rGO backbone, reducing the electron-hole pair recombination. The photocatalytic performance was optimized using methylene blue as a model organic dye under natural sunlight irradiation. The results were compared with pure and binary, MZG ternary nanocomposites exhibit superior photocatalytic activity. In a continuation of environmental remediation studies, MZG ternary nanocomposites revealed high antibacterial activity towards 〈em〉Escherichia coli (E.coli)〈/em〉 and 〈em〉Staphylococcus aureus (S.aureus)〈/em〉, highlighting its potential photocatalytic and antibacterial properties at different industrial and medical applications. This study may afford some inspiration for the rational design and facile synthesis of composite catalysts with a high and tunable catalytic property through a green, efficient pathway.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718310835-ga1.jpg" width="233" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 560〈/p〉 〈p〉Author(s): Anusha Chandra, Bhuvanesh E, Sujay Chattopadhyay〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Permselectivity and water uptake behaviors of anion exchange membrane (AEM) were investigated with organic acids. Contribution of the number of carboxyl group (acetic acid: AA, malic acid: MA, citric acid: CA) and hydrocarbon chain lengths (formic acid: FA, AA, propionic acid: PA and n-butyric acid: BA) in water uptake and permselectivity values were separately investigated with five different concentrations 0.025, 0.05, 0.075, 0.1 and 0.125 mol·L〈sup〉−1〈/sup〉 of each acid at two different pH 2.0 and 7.5 conditions. Microstructural changes occurring due to interaction of carboxylate anion and NR〈sub〉4〈/sub〉〈sup〉+〈/sup〉 groups of AEM resulted in permselectivity behavior. Permselectivity trend: CA 〈 MA 〈 AA could be explained by counter-ion condensation resulting out of strong counter-ion interactions with AEM fixed charges. Co-ion mobility values could explain variation in permselectivity at pH 2.0 and 7.5. While, water uptake and ionic size were dominant factors to explain the permselectivity trend: FA 〉 AA 〉 PA 〉 BA. Complex nature of interactions due to properties (size, charge, ionic charge density, mobility, diffusivity, stokes radius etc.) of carboxylate anions were explained using diffusivity ratio (counter/co-ion, 〈em〉D〈sub〉2〈/sub〉/D〈sub〉1〈/sub〉〈/em〉), adsorption equilibrium and fraction of dissociated species.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718313906-ga1.jpg" width="276" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 20 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 559〈/p〉 〈p〉Author(s): Svetlana Fedorenko, Alexey Stepanov, Rustem Zairov, Ondrej Kaman, Rustem Amirov, Irek Nizameev, Kirill Kholin, Ildus Ismaev, Alexandra Voloshina, Anastasiya Sapunova, Marsil Kadirov, Asiya Mustafina〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The present work introduces one-pot synthetic route to join ultra-small iron oxides (6 nm) with Gd(III) complexes in small (∼30 nm) silica nanoparticles with high longitudinal and transverse relaxivity values (r〈sub〉1〈/sub〉 = 34.7 mM〈sup〉−1〈/sup〉 s〈sup〉−1〈/sup〉 and r〈sub〉2〈/sub〉 = 64.7 mM〈sup〉−1〈/sup〉 s〈sup〉−1〈/sup〉 at 0.47 T). The design of the nanoparticles is based on the core-shell morphology, where the Gd(III) complexes were doped into the exterior silica layer. The doping mode is the reason for an efficient interfacial hydration and the small suppressing of r〈sub〉1〈/sub〉 by iron oxides. The measurements on the whole body scanner at 1.5 T confirm the high contrasting abilities of T〈sub〉1〈/sub〉 (Gd) and T〈sub〉2〈/sub〉 (iron oxide) components in the nanoparticles. Poor aggregation behavior of the nanoparticles in water is due to high electrokinetic potential value (−78 mV). Greater aggregation of the nanoparticles in the buffer solutions of bovine serum albumin enhances the disturbing effect of iron oxides on the longitudinal relaxation and facilitates the transverse relaxation. The higher surface activity of the nanoparticles results in their greater cytotoxicity versus the silica coated iron oxides, although the cytotoxicity is low in the concentration range which is within the region of interest for MRI technique.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718311166-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 560〈/p〉 〈p〉Author(s): Jiwei Lu, Mingjun Sun, Zhitao Yuan, Shengliang Qi, Zhongyun Tong, Lixia Li, Qingyou Meng〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Serpentine, as a common magnesium silicate mineral found in many ores around the world, is usually dispersed/depressed with the dispersants/depressants by adsorbing on the surface of serpentine. Therefore, in this work, the interaction mechanism of the dispersant of sodium hexametaphosphate (SHMP) was investigated in detail though solution chemistry calculations, Fourier transform infrared spectroscopy (FTIR) analyses, zeta potential measurements, adsorption and ion release tests, and molecular dynamics (MD) simulations. Results indicated that anionic components of H〈sub〉2〈/sub〉PO〈sup〉−〈/sup〉〈sub〉4〈/sub〉 and HPO〈sup〉2−〈/sup〉〈sub〉4〈/sub〉 in SHMP, as the predominant and effective species, adsorbed on the Mg and Si sites of the serpentine surfaces, which occurred on the Si site through the electrostatic interaction and on the Mg site through the chemical adsorption. As a result, the surface charge of serpentine was reversed from positive to negative at all pH region examined. In addition, ion release tests confirmed that SHMP dissolved some Mg ions for forming soluble complexes from the serpentine surface into the solution. Thus, the negative charge of it was further enhanced, which would lead to much stronger repulsion between negatively charge valuable minerals (e.g., pentlandite) and serpentine. Thus, the serpentine would be well dispersed with the valuable minerals.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718312329-ga1.jpg" width="398" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 560〈/p〉 〈p〉Author(s): Konstantin Popov, Maxim Oshchepkov, Elena Afanas’eva, Elena Koltinova, Yulia Dikareva, Hannu Rönkkömäki〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Scaling in reverse osmosis facilities, boilers, heat exchangers, evaporation plants, and oilfield applications is a serious problem worldwide. A widely used solution for controlling scale deposition is an application of chemical inhibitors. However, irrespective of the broad and a long-term antiscalant application, the mechanisms of scale inhibition are still the matter of discussions.〈/p〉 〈p〉In order to provide a new insight into the mechanism of the scale inhibition, a novel dynamic light scattering (DLS) special technique is used to study the bulk supersaturated gypsum aqueous solutions during the induction period. It is based on the standard Ag nanoparticles (ARGOVIT) injection into the supersaturated gypsum solution. These nanoparticles act as an internal indifferent light scattering intensity reference, and provide a semiquantitative measurement of a relative gypsum particles content in a blank solution and in the system treated with phosphonates: amino-tris(methylenephosphonic acid), ATMP; 1-hydroxyethane-1,1-bis(phosphonic acid), HEDP; 2-phosphonobutane-1,2,4-tricarboxylic acid, PBTC. It is found that ATMP sufficiently reduces the number of gypsum nuclei, spontaneously formed in the supersaturated solutions. The less effective inhibitors of gypsum scaling HEDP and PBTC also reduce the gypsum nuclei number, but to a less extent. A tentative nonconventional mechanism of scale inhibition in the bulk supersaturated aqueous solutions of gypsum is proposed.〈/p〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718307192-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 560〈/p〉 〈p〉Author(s): Hong-Liu Jiang, Jie-Ci Lin, Wei Hai, Hong-Wei Tan, Yu-Wei Luo, Xiao-Lin Xie, Yao Cao, Fu-An He〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this work, a novel crosslinked porous β-cyclodextrin-based polymer containing carboxylic acid groups (CT-β-CD) was synthesized successfully and characterized by SEM, FTIR, 〈sup〉13〈/sup〉C solid-state NMR, water-contact-angle measurement, and TGA. The resultant CT-β-CD with triple absorption effects including inclusion complextion, porous network capture, and electrostatic interaction was employed as an adsorbent for removing methylene blue dye from aqueous solution, which exhibited several advantages such as high absorption capacity (q〈sub〉max〈/sub〉 = 672 mg/g), rapid absorption rate, good recyclable ability, and selective adsorption for cationic dyes. The influences of initial MB concentration, absorption time, and pH value on the absorption behavior of CT-β-CD for MB were also investigated. In addition, it was found that the pseudo-second-order kinetic and the Langmuir model for adsorption isotherm could be used to describe the MB absorption behavior of CT-β-CD.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718313050-ga1.jpg" width="437" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 20 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 559〈/p〉 〈p〉Author(s): Qing Fan, Dali Zhou, Lei Yang, Jiabei Zhou, Shuang Yang, Yongqiang Yang〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Glass lubricants have great potential in industrial metal forming processes such as hot extrusion of titanium and titanium alloys. In this work, based on the extrusion process of commercial-purity titanium (TA2) at 800 °C, glass lubricants with low melting points are designed. The thermal properties, high-temperature oxidation resistance and friction properties of uncoated and glass-coated TA2 samples are systemically studied, which reveals the good lubricating and anti-oxidation properties of the samples. The glass lubricant melts into a viscoelastic film at 800 °C to insulate TA2 from oxygen and reduce friction, and automatically peel off during cooling due to the significantly mismatched thermal expansion between the glass coating and TA2 substrate. This work provides a guidance for designing glass-based lubricants used in hot extrusion of metals.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S092777571831152X-ga1.jpg" width="322" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 560〈/p〉 〈p〉Author(s): T. Rijnaarts, J. Moreno, M. Saakes, W.M. de Vos, K. Nijmeijer〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Reverse electrodialysis (RED) is a process to harvest renewable energy from salinity gradients. Under lab conditions with artificial salt solutions, promising results have been achieved in recent years. However, in large scale industrial applications, natural waters are used and that poses challenges such as fouling. Fouling of anion exchange membranes (AEMs) by organic matter (e.g. humic acids) has been identified as a possible cause that lowers RED performance with natural waters. In this work, natural river and seawater at the Afsluitdijk (The Netherlands) are used to study the RED performance of six different AEMs. These AEMs are characterized before and after RED experiments with natural waters. The effect of natural fouling is found to be specific for each AEM and highly dependent on their respective chemistries and associated membrane properties. Firstly, aromatic AEMs with a low swelling degree showed a permselectivity decrease as well as membrane resistance increase. Secondly, aliphatic AEMs with a medium swelling degree experienced only a membrane resistance increase. Finally, only a decrease in permselectivity was observed for aliphatic AEMs with large swelling degrees. Subsequently, the effect of AEM fouling is compared to the observed decrease in RED performance and this shows that AEM fouling can only explain a minor part of the losses in open circuit voltage (OCV). The RED power densities dropped by 15–20% over 12 days, independent of the AEMs selected, while the reduced AEM performance could only explain 2–4% of this reduction in power density. This demonstrates that next to AEM fouling, also other factors, such as spacer fouling, are expected to be the dominant fouling mechanism, reducing the performance to a much larger extent.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718313505-ga1.jpg" width="481" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 20 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 559〈/p〉 〈p〉Author(s): Yibo Ouyang, Jin Zhao, Ri Qiu, Shugang Hu, Yan Zhang, Peng Wang〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Bioinspired superhydrophobic and oil-infused surfaces have been recognized as interesting and promising materials for a wide range of applications correlated with water environment, such as corrosion and biofouling inhibition. Which material is the better choice still waits to reveal. In this study, taking stainless steel as the substrate, superhydrophobic and oil-infused surface based on Cu(OH)〈sub〉2〈/sub〉 matrix with prickly chestnut husk morphology is respectively obtained via successive steps. During the preparation of superhydrophobic surface, firstly, discrete Cu particles are electrodeposited onto stainless steel. After that, oxidation of the as-deposited Cu particles leads to the prickly Cu(OH)〈sub〉2〈/sub〉 following a dissolution-crystallization mechanism. Under a mild condition, dodecanethiol vapor modifies prickly matrix to achieve superhydrophobicity by anchoring the long-chain organic moiety onto Cu(OH)〈sub〉2〈/sub〉 surface. Since superhydrophobic matrix is intrinsically superoleophilic, oil-infused surface is finally constructed onto stainless steel. Taking typical marine fouling organisms including sulfate-reducing bacteria (SRB) and diatoms as the representatives, oil-infused surface can steadily prevent the biofouling on stainless steel, showing the better performance than superhydrophobic surface for biofouling inhibition. Using epoxy resin as the artificial fouling agent, the pulling force to remove the glued solid on oil infused surface is much lower than that on bare stainless steel, illustrating oil layer acting as the separation cushion between fouling agent and underneath substrate.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉 〈p〉Superhydrophobic and oil-infused surface based on prickly chestnut husk morphology Cu(OH)〈sub〉2〈/sub〉 are used as the representatives to illustrate which is the better choice to prevent marine biofouling.〈/p〉 〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718307477-ga1.jpg" width="295" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉 〈/div〉

Description: 〈p〉Publication date: 20 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 559〈/p〉 〈p〉Author(s): Chengyi Wang, Lin Chen, Shanshan Liu, Liang Zhu〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this study, nitrite desorption from activated carbon fiber (ACF) in capacitive deionization (CDI) and membrane capacitive deionization (MCDI) was examined and the effects of the operation parameters (pH, voltage, temperature and flow rate) and co-existing matters were deeply investigated. Desorption mechanisms were analyzed via Brunauer–Emmett–Teller (BET) and Fourier transform infrared spectroscopy (FTIR). Results showed that the final desorption ratio increased from 0 to 100% in MCDI and the enhancement was also observed in CDI that the ratio increased from 18.7 to 83.5% when solution pH increased from 2 to 10. Increasing the voltage and solution temperature also contributed to the ion desorption both in CDI and MCDI, while the effect of flow rate was negligible. Generally, MCDI showed greater desorption performance than CDI due to the elimination of co-ions effect. However, it was interesting to find that when the voltage was in the range of 0.4-0.6 V, the desorption ratio increased from 38.4% to 50.8% in MCDI which was lower than that in CDI (45.4% to 55.8%). One possible explanation was that the presence of membranes would inevitably introduce additional resistance into the system and decrease effective voltage especially at lower voltage. Compared to the desorption performance in MCDI when the solution pH was 2, the greater desorption performance was observed in CDI which was mainly attributed to the site competition. As for the influence of coexisting matters, the presence of bovine serum albumin (BSA) posed an adverse effect for the ion desorption both in CDI and MCDI. The inhibition effect was more serious in CDI, and pore blockage caused by BSA attachment onto ACF was the main mechanism. Therefore, this study would provide some referential advice for the investigation of ion desorption in CDI and MCDI.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718312275-ga1.jpg" width="255" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: Available online 28 June 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects〈/p〉 〈p〉Author(s): Anwesha Sarkar, Brent S. Murray〈/p〉

Description: 〈p〉Publication date: 5 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 560〈/p〉 〈p〉Author(s): Anh-Tu Ngo, Salvatore Costanzo, Pierre-Antoine Albouy, Vincent Russier, Sawako Nakamae, Johannes Richardi, Isabelle Lisiecki〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Novel colloidal crystals made of maghemite nanocrystals are fabricated by a co-evaporation method with a mixture of ethanol/hexane. Through a series of comprehensive characterization performed by grazing incidence small-angle X-ray scattering (GISAXS) and field emission gun scanning electron microscope (FEG-SEM), we show the first example of well-defined face-centered cubic (fcc) colloidal crystals. In order to obtain a clear picture of the crystal formation, the amount of ethanol in the solution is monitored using gas chromatography. In parallel, the interactions between the nanocrystals are calculated by statistical mechanics theory using solubility parameters. Theory predicts the formation of colloidal crystals at quite high amounts of ethanol around 15%, in perfect agreement with experimental results. We show that the theory can further be applied to predict the optimal experimental conditions for the formation of colloidal crystals using other solvent mixtures.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S092777571830788X-ga1.jpg" width="446" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 20 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 559〈/p〉 〈p〉Author(s): Xiaoyu Gao, Gang Wen, Zhiguang Guo〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Based on controlling ZnO nanoarrays morphology and employing fluorine-free modification agent, superhydrophobicity in air and superoleophobicity under water were successfully achieved on the prepared cotton fabric surfaces via a two-step hydrothermal reaction. To increase adhesion between ZnO crystal layer and substrate surface, two kinds of silane coupling agents (hydrophobic TTOP-12 and hydrophilic KH550) were added selectively in the pretreatment process. The as-prepared fabric exhibited great tolerance and durableness towards external harsh environments, such as mechanical abrasion, UV radiation, immersion of acid or alkali, and high temperature. In comparison, superhydrophobic fabrics showed superior separation effect for heavy oil and water mixture, while underwater superoleophobic fabric can also show efficient separation of water and light oil with high separation efficiency and flux. In a word, heavy/light oil and water mixtures can be separated efficiently as need by choosing cotton fabrics with various wettabilities.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉 〈p〉The cotton fabrics with superhydrophobic and superolephobic underwater were fabricated in this paper via controlling ZnO crystal morphology and choosing various modification agents, and the results showed that they possessed efficient separations as need for oil/ water mixtures with both an efficiency and a high flux.〈/p〉 〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718311129-ga1.jpg" width="386" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉 〈/div〉

Description: 〈p〉Publication date: 5 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 560〈/p〉 〈p〉Author(s): Zane A. Grady, Alexandria Z. Arthur, Christopher J. Wohl〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Controllable surface morphology is requisite across a gamut of processes, industries, and applications. The surface morphology of silica-coated polystyrene microspheres was controllably modified to enable generation of both smooth and bumpy, or raspberry-like, surfaces. Although smooth and raspberry-like silica shells on polystyrene templates have been demonstrated extensively, the method described here used readily available materials to produce radical changes in surface morphology from a single polystyrene template coated in silica through a facile sol-gel reaction processes. Silica shells were deposited via a sol-gel process (using tetraethyl orthosilicate as the silica precursor) onto 1 to 2 μm diameter anionic polystyrene spheres, fabricated by emulsifier-free polymerization. By varying the concentration of silica precursor and ammonium hydroxide catalyst and altering the electrostatic surface interactions via addition of a cationic polymeric brush, an array of surface topologies was generated. Incremented addition of the ammonium hydroxide base catalyst and sol-gel precursors generated smooth silica shells, whereas identical one-pot reactions led to raspberry-like shells. This modification of sol-gel deposition on large polystyrene cores via means of reactant addition offers additional control over sol-gel shell morphologies.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718313414-ga1.jpg" width="264" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 560〈/p〉 〈p〉Author(s): Mahsa Baghban Salehi, Mina Soleimanian, Asefe Mousavi Moghadam〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this paper, the overall performance of a disproportionate permeability reduction mechanism for a sulfonated polyacrylamide copolymer and the chromium triacetate crosslinker was investigated. A home-built gel filtration system was used for visual inspections and evaluations of the hydrogel performance. The experiments were conducted based on rheological test plans, energy-dispersive X-ray spectroscopy, and scanning electron microscope. Accordingly, quadratic equations based on the polymer and crosslinker concentrations were presented predicting the rupture pressure gradient of the hydrogel and the hydrogel output due to the oil and water injection through the hydrogel. It was indicated that the polymer concentration was the main effect on the rupture pressure gradient of the hydrogel and hydrogel output. Moreover, under constant concentration of crosslinker, increasing polymer concentration showed an increase in rupture pressure gradient and output of the hydrogel due to the increase of elastic modulus of hydrogel network and its strength as a viscoelastic material. As the hydrogel structure illustrated no rupture during the gel filtration experiments, a mechanism presented justifying the disproportionate permeability reduction phenomenon which in that under constant condition, the oil permeability through hydrogel was greater than the water permeability.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718312561-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 560〈/p〉 〈p〉Author(s): Tanara Sartori, Gabriela Feltre, Paulo Jose do Amaral Sobral, Rosiane Lopes da Cunha, Florencia Cecilia Menegalli〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This work aimed at evaluating the influence of glycerol concentration and storage relative humidity (RH) on gluten-based adhesive properties. Adhesive aging and adhesive application over different food substrates were also evaluated. For such purpose, three adhesive formulations were developed from different gluten:glycerol ratios (1:0.6, 1:1, and 1:1.4), which were applied over a pectin-based film as support material. The adhesives presented better adhesion and cohesion properties when stored at 58% RH. The formulation with the best adhesive properties was the 1:1 gluten:glycerol ratio. The degradation of the adhesives during aging was considered small in the first thirty days. The adhesives presented potential to be applied on food grade materials with low hydrophilicity.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718312032-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 560〈/p〉 〈p〉Author(s): Xuemei Zheng, Shiyu Fu〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Nanocellulose, a nano blocks extracted from plant biomass, is a potential candidate for fabricating superhydrophobic materials by reconstructing roughness surface and modifying with low-surface-energy chemicals. In this work, a facile spray drying was used to prepare the nanocellulose-based micro-particles with hierarchical surface structure. The surface structure of particles can be regulated by changing the size of nanocellulose. The prepared particles were modified with methyltrimethoxysilane (MTMS) by chemical vapor deposition (CVD), and then the modified particles mixed with polydimethylsiloxane (PDMS) proportionally are formulated a new coating, which can be sprayed on filter papers or glass to obtain superhydrophobic surface. The new finding is that the length of nanofiber had great influence on surface structure of formed particles from spray, and the shorter nano-fiber was easier to derive micro-particles with more compact, more even rough surface structure and better superhydrophobicity of final coated materials compared with the longer nanofiber. The superhydrophobic property of the coating can be controlled simply by changing the cellulose nano-fiber length, which is of great significance on hierarchical structure design of the nanocellulose-based superhydrophobic materials.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718307751-ga1.jpg" width="302" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 20 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 559〈/p〉 〈p〉Author(s): Erica Pensini, Abdallah Elsayed, Braulio Macias Rodriguez, Alejandro G. Marangoni, Ashutosh Singh, Brent Sleep, Gordon Hayward, Kristine Lamont, Christopher M. Collier〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Trapping and treating Cr(VI) is of great importance to environmental applications. In this work, the natural polymer scleroglucan and the reducing agent sodium thiosulfate were used to produce a water-based polymeric fluid to simultaneously trap and treat Cr(VI) in the subsurface. The thiosulfate reduced toxic Cr(VI) to less toxic Cr(III), as was apparent from fluid discoloration from bright orange to dark brown. Additionally, the viscosity of scleroglucan fluids containing sodium thiosulfate was low before mixing with Cr(VI) (150 mPa·s with 1 wt% scleroglucan in water at 23 °C), suggesting that the fluids can be effectively pumped in the subsurface. As sorption of scleroglucan onto geological substrates can affect its transport in geological media, sorption was measured using a Quartz-Crystal Microbalance with Dissipation Monitoring (QCM-D). Sorption of scleroglucan onto silica (used as a model geological substrate) was promoted in 100 mM CaCl〈sub〉2〈/sub〉 at pH = 7 and in deionised water at pH = 4, whereas it was hindered by humic acids (HA), which are usually naturally present in groundwater. Upon contact with Cr(VI) and sodium thiosulfate, scleroglucan chains crosslinked and the fluids gelled, acquiring high viscosity (approximately 2000 mPa·s) in water, in salt solutions (100 mM KCl or 100 mM CaCl〈sub〉2〈/sub〉) and in the presence of HA. Gelled scleroglucan was also characterized by high shear viscoelastic moduli and became plastic at high compressional loads (70 N to 100 N, depending on the water chemistry). Gelation is due to the crosslinking of scleroglucan by Cr(III), following the reduction of Cr(VI) by sodium thiosulfate. Scleroglucan fluids containing sodium thiosulfate may potentially form a barrier around the Cr(VI) contaminated zone, preventing its migration during treatment.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718311373-ga1.jpg" width="309" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 20 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 559〈/p〉 〈p〉Author(s): Patricio Serafini, Marcos Fernández Leyes, Jhon F. Sánchez M., Romina B. Pereyra, Erica P. Schulz, Guillermo A. Durand, Pablo C. Schulz, Hernán A. Ritacco〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The micellization process of the aqueous mixed system triton X-100 (TX100) – dodecyltrimethylammonium bromide (DTAB) has been studied with a battery of techniques: surface tension, static and dynamic light scattering and ion-selective electrodes. Results have been also analysed with two thermodynamic procedures: the Regular Solution Theory or Rubingh’s model and the recently developed Equation Oriented Mixed Micellization Model (EOMMM). For α〈sub〉DTAB〈/sub〉 ≤ 0.40 (α〈sub〉DTAB〈/sub〉: total molar fraction of the system without considering the water), the micelles are predominantly TX100 with scarce solubilized DTA〈sup〉+〈/sup〉 ions, with TX100 acting as a nearly ideal solvent. In the range 0.50 ≤ α〈sub〉DTAB〈/sub〉 ≤ 0.75, it seems that none of the components acts as a solvent. Above α〈sub〉DTAB〈/sub〉 ≈ 0.75 there are noticeable changes in the size and electrophoretic mobility of the micelles. These phenomena have been interpreted in the light of the thermodynamic results and literature on some TX100-ionic surfactant mixtures. The case under study is an almost ideal but very asymmetric mixed surfactants system, what is very interesting in view of the very different nature and structures of the components.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718310574-ga1.jpg" width="235" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: Available online 27 May 2017〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects〈/p〉 〈p〉Author(s): Johanna Milsmann, Kathleen Oehlke, Katrin Schrader, Ralf Greiner, Anja Steffen-Heins〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Edible solid lipid nanoparticles (SLN) stabilized by a mixture of food grade emulsifiers (soy bean lecithin, Tween 20, sucrose stearate) were added to o/w emulsions previously stabilized by anionic SDS, non-ionic Tween 20 or cationic CTAB. The aim of the study was to understand the fate of both SLN and oil droplets in these mixtures focusing on the impact of the surfactant used to stabilize the emulsion. The presence of SLN in emulsions led to increased emulsion stability as reflected by droplet size measurements and accelerated creaming experiments. This could be attributed to an increase in the viscosity of the sample, but also to changed properties of the o/w interface. Zeta potential measurements revealed that the surfactant composition at the o/w interface had changed in SDS and CTAB stabilized but not in Tween 20 stabilized emulsions. SLN remained detectable in the continuous phase of each emulsion system over three weeks of storage but were not detected at the o/w interface of oil droplets. The particle size of the SLN remained unchanged whereas their zeta potential increased in SDS and CTAB stabilized emulsions to a similar magnitude (+/− 68 mV) but opposite signs. The melting temperature and melting enthalpy of SLN decreased in emulsions indicating that part of the lipid matrix was dissolved by oil from the emulsion. Accordingly, a time-dependent transfer of crystalline triglycerides originating from the SLN into the oil phase of separated model emulsion systems was verified.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775717305046-fx1.jpg" width="450" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 20 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 559〈/p〉 〈p〉Author(s): S. Nazari, S.Z. Shafaei, B. Shahbazi, S. Chehreh Chelgani〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Recent investigations indicated that using nanobubbles (NBs) in flotation separation of fine particles (〈25 μm) has several advantages; however, a detail study on performances of various flotation parameters (such as hydrodynamic variables and particle properties) and their impacts on recovery of coarse particles (〉100 μm) in the presence of NBs have not been fully understood. This work was explored how NBs can change impacts of Reynolds number, conventional flotation bubbles (CBs), air flow rate and particle sizes on flotation recovery of coarse particles (−425 + 106 μm). Several flotation experiments were carried out by using pure quartz in the presence and absence of NBs. Kendall’s tau (τ) as an accurate statistical method was introduced and applied through the provided dataset from the experiments to assess the impacts of NBs. In the absence of NBs; τ assessments demonstrated that there are negative correlations between particle size, air flow rate, Reynold number and recovery (τ ∼ −0.81, −0.18 and −0.12, respectively), and a positive relationship between CBs and recovery (τ ∼ 0.08). In general, results indicated that recovery of coarse particles was increased by ∼14% (on average) in the presence of NBs; however, the magnitude of relationships was not changed (just correlations between Reynolds and CBs vs. recovery were changed: τ ∼ −0.17 and 0.13, respectively). Assessing the simultaneous impacts of Re and CBs on recovery showed that in the presence of NBs; the highest recovery (on average) may receive in lower Re values and higher CB sizes in comparison with in the absence of NBs. Taking all these interactions into consideration, it can be concluded that increasing the rate of bubble-particle attachment and decreasing the impact of Re can be the main reasons for the enhancement of coarse particle recovery in the presence of NBs.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718307635-ga1.jpg" width="243" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 5 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 560〈/p〉 〈p〉Author(s): Lev O. Filippov, Inna V. Filippova, Zineb Lafhaj, Daniel Fornasiero〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The adsorption mechanism of collector mixtures and the implication for mineral flotation are discussed in light of the results of a quantitative study of the flotation of fluorapatite and calcite with mixtures of fatty alcohol and oleate collectors. It was found that the recovery of fluorapatite and calcite floated with oleate improved considerably after addition of the fatty alcohol. With oleate alone, the low mineral flotation was attributed to a patchy oleate surface coverage and oleate dimers but with the collector mixture it was shown that the fatty alcohol co-adsorbs with oleate on the mineral surface and in a much larger quantity than when it was used alone. Spectroscopic analyses reveal that the amount of oleate adsorbed remains similar when added alone or in mixtures, which implies that the co-adsorption of the fatty alcohol is responsible for the improved mineral flotation. Replacement of oleate dimers with fatty alcohol-oleate complexes at the mineral surface may also explain the increase mineral hydrophobicity and flotation.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉 〈p〉Infrared spectra of fluorapatite (Fap) with fatty alcohol (PX) or oleate (Ol) alone, and with Ol+½PX, Ol + PX or Ol+2PX mixtures at pH 9.0.〈/p〉 〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718308112-ga1.jpg" width="278" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉 〈/div〉

Description: 〈p〉Publication date: 5 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 560〈/p〉 〈p〉Author(s): Xudong Wang, Zhangjun Chen, Ke Li, Xiaodong Wei, Zhenbin Chen, Juan M. Ruso, Zhenghua Tang, Zhen Liu〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this work, titanium dioxide particle was firstly modified with glutaraldehyde, and modification conditions, i.e. particle size (〈em〉d〈/em〉), active temperature (〈em〉T〈sub〉a〈/sub〉〈/em〉), modification temperature (〈em〉T〈sub〉m〈/sub〉〈/em〉), modification time (〈em〉t〈sub〉m〈/sub〉〈/em〉), pH value, aldehyde ethanol ratio (〈em〉R〈sub〉a〈/sub〉〈/em〉) and ethanol ratio (〈em〉R〈sub〉e〈/sub〉〈/em〉), were studied and optimized adopting grafting rate (〈em〉G〈sub〉r〈/sub〉〈/em〉) as the optimizing index, the ultraviolet-visible spectrophotometry as characterization method, and the obtained optimal modification conditions were 〈em〉d〈/em〉 = 3.3 μm, 〈em〉T〈sub〉a〈/sub〉〈/em〉 = 120 °C, 〈em〉T〈sub〉m〈/sub〉〈/em〉 = 45 °C, 〈em〉t〈sub〉m〈/sub〉〈/em〉 = 30 h, pH = 6.0, 〈em〉R〈sub〉a〈/sub〉〈/em〉 = 1:10 and 〈em〉R〈sub〉e〈/sub〉〈/em〉 = 100%. Under the optimal conditions, 〈em〉G〈sub〉r〈/sub〉〈/em〉 of glutaraldehyde arrived at 50%. Thereafter, a series of modified titanium dioxide with 〈em〉G〈sub〉r〈/sub〉〈/em〉 in the range of [8%, 46%] and with 〈em〉G〈sub〉r〈/sub〉〈/em〉 = 30% obtained from different modification conditions were adopted to study the immobilization of penicillin G acylase (PGA), during this process, the ultraviolet-visible spectrophotometry of 6-aminopenicillanic acid was conscripted as characterization method, the enzyme loading capacity (〈em〉ELC〈/em〉), the enzyme activity (〈em〉EA〈/em〉) and enzyme activity retaining ratio (〈em〉EAR〈/em〉) were explored, and results documented with the increase of 〈em〉G〈sub〉r〈/sub〉〈/em〉, 〈em〉ELC〈/em〉, 〈em〉EA〈/em〉 and 〈em〉EAR〈/em〉 increased. As 〈em〉G〈sub〉r〈/sub〉〈/em〉 kept as a similar level, 〈em〉ELC, EA〈/em〉 and 〈em〉EAR〈/em〉 also showed a similar value. Finally, the structure of titanium dioxide, glutaraldehyde modified titanium dioxide and PGA immobilized titanium dioxide was characterized by the flourier transform infrared spectroscopy (FTIR), and results exhibited aimed samples were obtained successfully.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718312792-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 20 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 559〈/p〉 〈p〉Author(s): Priya A., Prabhakarn Arunachalam, Selvi A., Madhavan J., Abdullah M. Al-Mayouf〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The present study demonstrates the synthesis of pure bismuth iron tungstate (BiFeWO〈sub〉6〈/sub〉) and tungsten oxide (WO〈sub〉3〈/sub〉) nanorods by simple co-precipitation and hydrothermal methods respectively. Likewise, BiFeWO〈sub〉6〈/sub〉/WO〈sub〉3〈/sub〉 nanocomposites of different compositions (1, 2 and 3 wt %) were fabricated via convenient wet-chemical route. The fabricated BiFeWO〈sub〉6〈/sub〉/WO〈sub〉3〈/sub〉 nanocomposites were investigated by numerous methods like X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDS) and photoelectrochemical (PEC) studies. Moreover, the photodegradation efficiency of the fabricated composites was demonstrated by photodegradation of Rhodamine B (RhB) under visible-light illumination. In particular, photodegradation results revealed the improved photocatalytic performance of 1% BiFeWO〈sub〉6〈/sub〉/WO〈sub〉3〈/sub〉 than the independent WO〈sub〉3〈/sub〉. This observed enhancement was credited to the restricted recombination rate of charge carriers by the composites leads to their separation. The as-synthesized BiFeWO〈sub〉6〈/sub〉/WO〈sub〉3〈/sub〉 photocatalytic materials were found to possess a reasonably good photostability, reusability and superior photocatalytic performances than the pure WO〈sub〉3〈/sub〉. Therefore, it can be used as a potential photocatalysts towards elimination of various organic pollutants present in aqueous environment. Further, a schematic charge transfer mechanism was also proposed in the present study.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718310781-ga1.jpg" width="211" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: 20 December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 559〈/p〉 〈p〉Author(s): Zahra Mohammadizadeh Tahroudi, Amir Razmjou, Mojtaba Bagherian, Mohsen Asadnia〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Over the last decade, polydopamine (PDA) has attracted significant attention due to its material-independent coating ability, process simplicity, and its powerful capabilities for ad-layer formation. However, its long coating time (24 h) has limited its application in industrial scale. To address this issue, oxidants such as (NH〈sub〉4〈/sub〉)〈sub〉2〈/sub〉S〈sub〉2〈/sub〉O〈sub〉8,〈/sub〉 CuSO〈sub〉4,〈/sub〉 and NaIO〈sub〉4〈/sub〉 were introduced to enhance the coating kinetically. Although NaIO〈sub〉4〈/sub〉, among all the oxidants, was reported as the most efficient one, its high stoichiometric ratio of 2 between the oxidant and dopamine makes it costly and less attractive. Here, KMnO〈sub〉4〈/sub〉 is introduced as a new water-soluble oxidant which can substantially reduce the PDA coating to few minutes in a single reaction process with a chance to adjust its thickness without losing PDA intrinsic modification capability. At a KMnO〈sub〉4〈/sub〉/dopamine ratio of 0.4, a coating speed of 750 nm/h was achieved, which is 25 times higher than that of NaIO〈sub〉4〈/sub〉 at similar oxidant/dopamine ratio. The KMnO〈sub〉4〈/sub〉-assisted PDA coating was utilized to introduce an efficient and inexpensive method to convert glass materials to surfaces with durable UV shielding property. Finally, the reducibility and ad-layer formation ability of PDA layer were used to develop silver, copper, and ZIF8 composite PDA layer to adjust the UV protection level.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0927775718307209-ga1.jpg" width="355" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉