ALBERT

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Zhi-Hu Wang, Hong-Wei He, Guo-Sai Liu, Xu Yan, Xin Ning, Yun-Ze Long〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In conventional electrospinning (e-spinning) process, the curing mechanism can be attributed to the volatilization of solvent or the melt cooling of the jets, which were merely physical processes. To develop novel e-spinning curing mechanism, we propose a conjugate e-spinning one, in which the e-spinning precursors, solution A containing some active monomers, oxidant and solution B containing reductant, are loaded into two different syringes connected with opposite high voltage supplier, respectively. The opposite charged jets attract each other and then meet when flying from spinneret tip to collector. The redox reaction occurs when two jets meet and radicals are produced in situ which can initiate polymerization of active monomers. Then the conjugate jets solidify into fibers under reaction curing mechanism. The new method may give a new approach to produce composite functional fibers.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉 〈p〉Two solutions containing oxidant and reductant, respectively are electrospun into fibers via a conjugate electrospinning process under a reaction curing mechanism.〈/p〉 〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19309954-ga1.jpg" width="271" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 253〈/p〉 〈p〉Author(s): Ji Soo Yu, Sung Hun Kim, Minh Tan Man, Hong Seok Lee〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We have successfully demonstrated the colloidal hot-injection process to easily obtain the Mn-doped ZnSe quantum dots (QDs) with a size of about 4–5 nm, and 〈em〉d〈/em〉-spacing is 0.31 nm, corresponding to the (1 1 1) lattice plane of ZnSe. Experimental results show that UV–vis absorption and fluorescence spectra were recorded to elucidate the role of Mn〈sup〉2+〈/sup〉 ions substituted into ZnSe, which resulted in the carrier transfer of luminescent sites by a small amount of Mn〈sup〉2+〈/sup〉 dopant. The small size of the Mn-doped ZnSe QDs offers intriguing opportunities for their application in photonic, bioimaging, and spintronics devices.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19309905-ga1.jpg" width="298" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Mohamad Fahrul Radzi Hanifah, Juhana Jaafar, M.H.D. Othman, A.F. Ismail, M.A. Rahman, Norhaniza Yusof, Farhana Aziz〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Nanocluster-like Pt nanoparticles/reduced graphene oxide nanocomposite catalyst (NC-PtNPs/RGO) was synthesized through a novel one-step process of chemical reduction-assisted hydrothermal reaction by using formic acid as reducing agent. The crystallinity, morphology and composition of the NC-PtNPs/RGO catalysts were extensively characterized. The as-prepared NC-PtNPs/RGO catalysts exhibited higher electro-catalytic activity towards methanol oxidation than carbon black (CB)/PtNPs catalyst and could be ascribed to the high dispersion of NC-Pt NPs with large electrochemical surface area, release more exposure of active sites by NC-PtNPs structure and synergy effect of RGO.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 253〈/p〉 〈p〉Author(s): Zhenhua Wang, Yi Liu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Σ3 boundaries improve the intergranular corrosion resistance of high nitrogen austenitic stainless steels. However, the regeneration of these boundaries is, unfortunately, accompanied by significant grain coarsening. 18Mn18Cr0.5N and 18Mn18Cr0.6N steels were thermo-mechanically processed and the corresponding microstructures were evaluated. Formation mechanisms were proposed for Σ1 boundaries in different R-Σ3-Σ1-type junctions. These boundaries formed during grain growth accompanying Σ3 formation and reaction. After 30% cold tension and cyclic heating between 500 °C and 1100 °C, numerous Σ1 boundaries were formed and disrupted the high angle grain boundary network efficiently. Moreover, a small grain size was maintained. Σ1 boundaries have significant application potential in grain boundary engineering.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Rui Wang, Dongdong Gu, Lixia Xi, Kaijie Lin, Meng Guo, Hongmei Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Selective laser melting (SLM), as a rapidly developed layer-by-layer 3D printing technology, has been demonstrated that it can be used for additive manufacturing of multi-materials. In this work, TiB〈sub〉2〈/sub〉/Ti6Al4V multi-materials were manufactured by SLM. The results showed that interfacial microstructures consisting of un-melted TiB〈sub〉2〈/sub〉 powders, columnar TiB crystals, and acicular TiB crystals were formed in the molten pool. Meanwhile, a variation nanohardness was developed with chemical compositions at the interfacial regions, owing to an in-situ reaction of Ti and TiB〈sub〉2〈/sub〉. The first-principle calculations were used to reveal the axial growth of TiB crystals as well as the different hardness of this system.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19310006-ga1.jpg" width="346" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 253〈/p〉 〈p〉Author(s): Siyao Xie, Ruidi Li, Linjun Tang, Tiechui Yuan〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The diffusion behavior of Al in FeCoCrNiMo〈sub〉x〈/sub〉 high-entropy alloys (HEAs) at temperatures ranging from 773 to 873 K with and without pulse current was studied in this paper. The diffusion coefficients 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si2.svg"〉〈mi〉D〈/mi〉〈/math〉 was determined based on the Fick’s law and corresponding pre-exponential factor 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si3.svg"〉〈msub〉〈mi〉D〈/mi〉〈mn〉0〈/mn〉〈/msub〉〈/math〉, as well as activation energy 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si4.svg"〉〈msub〉〈mi〉Q〈/mi〉〈mi〉D〈/mi〉〈/msub〉〈/math〉. It was found that the 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si2.svg"〉〈mi〉D〈/mi〉〈/math〉 under pulse current dramatically increased about hundreds of times in contrast with that without current. In addition, the 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si3.svg"〉〈msub〉〈mi〉D〈/mi〉〈mn〉0〈/mn〉〈/msub〉〈/math〉 and 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si4.svg"〉〈msub〉〈mi〉Q〈/mi〉〈mi〉D〈/mi〉〈/msub〉〈/math〉 were determined to reduce from 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si5.svg"〉〈mrow〉〈msubsup〉〈mrow〉〈mn〉1.369〈/mn〉〈/mrow〉〈mrow〉〈mo〉-〈/mo〉〈mn〉0.324〈/mn〉〈/mrow〉〈mrow〉〈mo〉+〈/mo〉〈mn〉0.424〈/mn〉〈/mrow〉〈/msubsup〉〈mo〉×〈/mo〉〈msup〉〈mrow〉〈mn〉10〈/mn〉〈/mrow〉〈mrow〉〈mo〉-〈/mo〉〈mn〉13〈/mn〉〈/mrow〉〈/msup〉〈/mrow〉〈/math〉 to 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si17.svg"〉〈mrow〉〈msubsup〉〈mrow〉〈mn〉5.016〈/mn〉〈/mrow〉〈mrow〉〈mo〉-〈/mo〉〈mn〉1.984〈/mn〉〈/mrow〉〈mrow〉〈mo〉+〈/mo〉〈mn〉3.284〈/mn〉〈/mrow〉〈/msubsup〉〈mo〉×〈/mo〉〈msup〉〈mrow〉〈mn〉10〈/mn〉〈/mrow〉〈mrow〉〈mo〉-〈/mo〉〈mn〉15〈/mn〉〈/mrow〉〈/msup〉〈/mrow〉〈/math〉 m〈sup〉2〈/sup〉/s, and from 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si6.svg"〉〈mrow〉〈mn〉39.7〈/mn〉〈mo〉±〈/mo〉〈mn〉1.8〈/mn〉〈/mrow〉〈/math〉 to 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si18.svg"〉〈mrow〉〈mn〉21.6〈/mn〉〈mo〉±〈/mo〉〈mn〉3.4〈/mn〉〈/mrow〉〈/math〉 kJ/mol respectively with the Mo contents increasing from Mo〈sub〉0〈/sub〉 to Mo〈sub〉0.2〈/sub〉 without pulse current. The introduction of pulse current into the diffusion couples dramatically promoted the 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si3.svg"〉〈msub〉〈mi〉D〈/mi〉〈mn〉0〈/mn〉〈/msub〉〈/math〉 at all the diffusion couples. However, the pulse current was ascertained to obviously increase the 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si4.svg"〉〈msub〉〈mi〉Q〈/mi〉〈mi〉D〈/mi〉〈/msub〉〈/math〉 in contrast to that of diffusion couples without pulse current.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19309899-ga1.jpg" width="271" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): C.Q. Zhang, W. Liu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The Al〈sub〉3〈/sub〉Ti intermetallic compound (IMC) layer growth kinetics at Al-Ti interface was investigated. Surprisingly an abnormal effect of temperature was observed with a thicker IMC layer formed at lower annealing temperature due to the much faster Al〈sub〉3〈/sub〉Ti grain coarsening at a higher temperature, the IMC layer growth at 630 °C became slower than that at 600 °C after a certain annealing time. The quantitative influence of grain size on effective diffusion coefficient was analysed. Calculations showed that the lattice diffusion makes little contribution to the effective diffusion coefficient. Grain boundary diffusion, therefore, dominates for all the annealing conditions studied.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 253〈/p〉 〈p〉Author(s): Camila Machado de Oliveira, Thuani Gesser Müller, Rafael Alves André, Elen Machado de Oliveira, Elis Machado de Oliveira, Michael Peterson, Fabiano Raupp-Pereira〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Pyrite is part of the tailings from coal mining and presents a great valorization potential technological, economic and environmental in the production of nanoparticles. In this work, pyrite from coal mining was subjected to high-energy milling and the particle size reduction, electrical and optical properties were evaluated. With the milling parameters used, the apparent size of the crystallites was reduced from 34.7 nm to 23.8 nm, resulting in highly unstable particles and charge carriers with low mobility. Due to this instability, submicron particles were observed, in the range of 300–500 nm, with a hydrodynamic diameter of 1257 ± 36 nm. The processed pyrite showed good visible light absorption and an indirect band gap of 1.51 eV.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 253〈/p〉 〈p〉Author(s): Zunyu Ke, Changbo Yi, Lei Zhang, ZhengYuan He, Jun Tan, YeHua Jiang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The Ti-13Nb-13Zr-10Cu alloy as new biomedical material was prepared by Ar-arc melting. The microstructure characteristics, mechanical properties and antibacterial properties of Ti-13Nb-13Zr-10Cu alloy after heat treatment were studied. Results show that the Ti-13Nb-13Zr-10Cu alloy is mainly composed of 〈em〉β〈/em〉-Ti, 〈em〉α〈/em〉-Ti, and some Cu-containing phases, 〈em〉e.g.〈/em〉 CuZr, Ti〈sub〉2〈/sub〉Cu, and Cu〈sub〉10〈/sub〉Zr〈sub〉7〈/sub〉. With the addition of Cu, the 〈em〉α〈/em〉-Ti phase significantly decreased, and some Cu-containing phases appeared in the form of reticular structure, which was mainly consisted of Cu, Zr and Ti elements. The CuZr and Ti〈sub〉2〈/sub〉Cu phases in the reticular structure were identified by TEM. Compared with CP-Ti and Ti-13Nb-13Zr alloy, the elastic modulus of Ti-13Nb-13Zr-10Cu alloy was significantly reduced to 66 GPa, but its yield strength and compressive strength still retained at high levels. The Ti-13Nb-13Zr-10Cu alloy after 24 h of culture with 〈em〉S. aureus〈/em〉 exhibits an enhanced antibacterial activity.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 253〈/p〉 〈p〉Author(s): Liman Zhao, Zechuan Yang, Yanchun Li, Tongfei Shi, Danfeng Pei, Fan Li〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Biomimetic glycopolymers poly(dopamine methacrylamide-〈em〉co〈/em〉-lactobionamidoethyl methacrylate) (PDMA〈em〉-co-〈/em〉PLAMA) based ligand was synthesized, used to effectively reduce the gold ions and anchored on the surface of gold nanoparticles to prepare the glycopolymers modified gold nanoparticles (Gly@AuNPs). The Gly@AuNPs were prepared and stabilized in one step, which did not require classical thiol-containing polymer to stabilize AuNPs. The Gly@AuNPs were found to be highly stable at high salt concentrations (500 mM NaCl) and different pH conditions over a long time. These stable Gly@AuNPs could provide useful information in applications of targeted cancer imaging and photothermal therapy.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X1930970X-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 253〈/p〉 〈p〉Author(s): Yuhua Chen, Huaibo Deng, Hao Liu, Timing Zhang, Shuhan Li, Shanlin Wang, Chao Chen〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This study used an unconventional friction melt-bonded spot welding (FMSW) to improve the mechanical performance of dissimilar Ti/Al joints. The temperature, microstructure, and mechanical properties were investigated. Results showed that FMSW was a suitable method to form nanoscale Al〈sub〉3〈/sub〉Ti at Ti/Al interface. The maximum tensile shear load of joints reached 18.2 kN.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 253〈/p〉 〈p〉Author(s): Ting Zhang, Qing Fan, Xiaoli Ma, Wen Wang, Kuaishe Wang, Pingquan Shen, Junlin Yang, Liqiang Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The strengthening effect of laser remelting on Ti-35Nb-2Ta-3Zr alloy was studied in this study. The surface of the material changed from an equiaxed crystal to a needle-like structure after laser remelting. Dislocations and ω phases were observed during the process, and the orientation relationship between ω phase and β matrix was identified as [11 0]β//〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.svg"〉〈mrow〉〈mo stretchy="false"〉[〈/mo〉〈mn〉11〈/mn〉〈mover〉〈mn〉2〈/mn〉〈mo〉-〈/mo〉〈/mover〉〈mn〉0〈/mn〉〈mo stretchy="false"〉]〈/mo〉〈mi mathvariant="normal"〉ω〈/mi〉〈/mrow〉〈/math〉. The microhardness of the laser-remelted alloy increased significantly.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Hang Yin, Dafeng Hu, Xuemin Geng, Hu Liu, Yanfen Wan, Zhanhu Guo, Peng Yang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We demonstrate heterogeneous integration of 2D self-assembled films of Au nanoparticles (NPs) and 2D MoS〈sub〉2〈/sub〉 monolayer. The Au NPs film has a compact, long-range-ordered structure, with its particles exhibiting a narrow size distribution. In addition, large-area coverage was achieved between the two components. Photoluminescence (PL) quenching was observed after the attachment of Au NPs film onto MoS〈sub〉2〈/sub〉 monolayer, which was attributed to electron transfer and shielding of light by Au NPs film. This work broadens our understanding of PL properties in such 2D hybrids.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Haijuan Zhan, Na Zhang, Dan Wu, Zhiqiang Wu, Shuxian Bi, Baojun Ma, Wanyi Liu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉β-SiC was synthesized with coal and sodium silicate as the raw materials via a novel microwave sintering method. The uniform heating and short production cycle makes the microwave sintering process more energy efficient. The structure and property of the prepared samples were characterized using XRD, FT-IR, XPS, TEM and HRTEM techniques. The size of nano-scaled β-SiC range from 70 to 300 nm in diameter and can be achieved 75.7% in the silicon carbide products under the condition of 1600 °C × 60 min with microwave controlling.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Tao Tao, Guangyao Li, Yanli He, Pengzheng Duan〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Carbon nanotubes/graphene/nickel (CNT-G-Ni) fluffy spheres were synthesized using renewable carbon sources. Carbon-encapsulated nickel nanoparticles (CENNs) were prepared by hydrothermal carbonization (HTC) of potato starch and nickel nitrate, and then followed by catalytic graphitization at 900 °C. The prepared GENNs were cracked at 700 °C in biogas, during which graphene shells over GENNs were peeled off and formed graphene nanoplatelets, and simultaneously multiwall carbon nanotubes (MWCNTs) were formed over nickel particles and in-situ integrated into graphene nanoplatelets to obtain CNT-G-Ni fluffy spheres. The prepared 3D nanocomposite was investigated for the removal of organic solvent from water and its adsorption capacity above 110 g/g.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Fuxiang Wei, Wei Liu, Xuping Zhang, Xin Liu, Yanwei Sui, Jiqiu Qi〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this study, due to the large cavity structure of the metal-organic frameworks (MOFs), Au@ZIF-67 was synthesized by loading nanoscale Au nanoparticles (NPs) into Co based zeolite imidazole framework (ZIF-67). Subsequently, Au@ZIF-67 was calcined to produce Au NPs loading Co〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 hollow nanocages (Au@Co〈sub〉3〈/sub〉O〈sub〉4〈/sub〉). The small size Au NPs were distributed on the wall of Co〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 hollow nanocages. The final product in a polyhedral morphology formed hollow nanocages. The unique structure could provide a high specific surface area. As an electrode material of supercapacitors, the Au@Co〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 electrode with polyhedral morphology showed a specific capacity of 763 F·g〈sup〉−1〈/sup〉 at a current density of 1 A g〈sup〉−1〈/sup〉 in 2.0 M KOH electrolyte. In addition, the specific capacitance retention rate was 83.7% at a current density of 10 A g〈sup〉−1〈/sup〉 after 5000 cycles. These results indicate that Au@Co〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 electrodes with polyhedral morphology have very wide application prospects in supercapacitors.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Baoe Li, Zhenghao Sun, Yan Zhao, Zisheng Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Lithium-sulfur batteries were considered as a new generation of high energy density batteries, but their commercialization was limited by volume expansion, the low conductivity of sulfur and shuttle effect. To overcome these issues, we developed a three-dimensional carbon nanotube/Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 microspheres via spray drying and calcination as sulfur host materials (S/CNT/Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉). In this three-dimensional microsphere structure, interwoven CNT backbone offers a robust conductive network with sufficient space for loading sulfur, and the polar Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 nanoparticles can enhance chemical adsorption of polysulfide. Benefiting from these advantages, the S/CNT/Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 cathode exhibit high initial discharge capacity (1270 mAh g〈sup〉−1〈/sup〉 at 0.2 C), superior rate performance (602 mAh g〈sup〉−1〈/sup〉 at 3 C), and long cyclic stability (only 0.084% capacity decay per cycle for 300 cycles at 1 C).〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Quande Che, Yujie He, Qian Ma, Junpeng Wang, Gang Wang, Yuanna Zhu, Ruixia Shi, Ping Yang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This paper reports a nanoflakes-assembled 3D flower-like nickel hydroxidenitrate (NiNH) and its application in water oxidation. It is demonstrated for the first time that the NiNH is an efficient oxygen evolution reaction (OER) electrocatalyst in alkaline solution. Specifically, it can drive a current density of 10 mA cm〈sup〉−2〈/sup〉 at a fairly low overpotential of 280 mV and a correspondent small Tafel slope of 39.6 mV dec〈sup〉−1〈/sup〉. The impressive OER catalytic activity of the as-prepared NiNH can be ascribed to its favorable 3D hierachical microstructure. The present research not only provide us a prospective and cost-effective electrocatalyst for water splitting but also affords us an inspiration for designing effective transition-metal based electocatalysts through microstructure regulation.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Jia Zhou, Qingan Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this work, the hydrogen absorption and desorption properties of a melt-spun Mg〈sub〉86〈/sub〉Pr〈sub〉3〈/sub〉Al〈sub〉11〈/sub〉 alloy were studied using a Sieverts-type apparatus. It was found that the melt-spun Mg〈sub〉86〈/sub〉Pr〈sub〉3〈/sub〉Al〈sub〉11〈/sub〉 alloy exhibits an enhanced cycle durability of hydrogen absorption and desorption. After fifty hydrogen absorption and desorption cycles at 300 °C, the capacity retention rate is about 97% and the hydrogen sorption kinetics undertakes only a slight degradation, which is related to the existence of PrAl〈sub〉2〈/sub〉 and Pr〈sub〉3〈/sub〉Al〈sub〉11〈/sub〉 phases in the melt-spun Mg〈sub〉86〈/sub〉Pr〈sub〉3〈/sub〉Al〈sub〉11〈/sub〉 alloy.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Meihua Fang, Jinpeng Lv〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Passive thermal control coatings (TCCS) have been widely used to tune the thermal equilibrium of spacecraft. However, the performance of such coatings undergoes serious degradation due to the intensive UV absorption and the radiation damage of the pigments. We developed a Zn〈sub〉2〈/sub〉SiO〈sub〉4〈/sub〉 pigment with a solar absorptance (α〈sub〉s〈/sub〉) as low as 0.078, which shows a distinctly high reflectance in the whole solar-radiation spectrum, especially in the high energy UV wavebands. Furthermore, after performing proton irradiation, the α〈sub〉s〈/sub〉 of ZnO, ZnTiO〈sub〉3〈/sub〉 pigments increase from 0.153 and 0.101 to 0.277 and 0.521, respectively, while Zn〈sub〉2〈/sub〉SiO〈sub〉4〈/sub〉 rises to 0.212, which exhibits remarkable radiation resistance. We evidenced that Zn〈sub〉2〈/sub〉SiO〈sub〉4〈/sub〉 pigments will not only significantly boost the performance of thermal control coatings but also be beneficial for UV shielding applications.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉 〈p〉The as-developed Zn〈sub〉2〈/sub〉SiO〈sub〉4〈/sub〉 pigments show ∼95% reflectivity in solar UV wavebands. The α〈sub〉s〈/sub〉 of ZnSi〈sub〉2〈/sub〉O〈sub〉4〈/sub〉 only degrades to 0.212 after performing proton irradiation with a 10-year GEO dose.〈/p〉 〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X1931153X-ga1.jpg" width="272" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Ye Tian, Xiangchao Pang, Bin Tang, Xing Cheng〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Nanoimprint, an important nanofabrication technology, is widely adopted to produce the microstructure. In this study, nanoindentation was employed to quantitatively characterize the elastic modulus of nanoimprinted poly(methyl methacrylate) (PMMA) under different conditions, with the purpose to investigate the mechanical property of the nanoimprinted microstructure suffered the ultra-high local stress and temperature. It is indicated that the elastic modulus of samples increases with the increasing the residual stress and the nanoimprint temperature. Moreover, the optical birefringence method was performed to investigate the distribution of residual stress on the microstructure. It was shown that high elastic modulus region also exhibited high residual stress. Therefore, we suggested that the temperature during the embossing process should be rigorously considered in nanoimprint process to obtain a mechanical homogeneity of imprinted structures.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Hairui Huang, Zhijie Zhang, Shaoke Guo, Kun Cheng, Jiayue Xu, Na Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Graphitic carbon nitride (g-C〈sub〉3〈/sub〉N〈sub〉4〈/sub〉) photocatalyst has a promising application prospect in solving environment problems and energy crisis. In order to improve the photocatalytic activity of g-C〈sub〉3〈/sub〉N〈sub〉4〈/sub〉, a novel TCNAQ/g-C〈sub〉3〈/sub〉N〈sub〉4〈/sub〉 organic hybrid photocatalyst was designed by introducing 11,11,12,12-tetracyanonaphtho-1,4-quinodimethane (TCNAQ) as an electron acceptor. Due to the interfacial charge-transfer transitions between g-C〈sub〉3〈/sub〉N〈sub〉4〈/sub〉 donor and TCNAQ acceptor, separation and migration of photo-induced charge carriers were promoted, while their recombination was prohibited, which led to enhanced photocatalytic performance in pollutant degradation. This work provides a strategy to produce efficient hybrid photocatalysts with high light-to-current conversions due to the interfacial charge-transfer transitions, which have potential applications in light-to-energy conversions.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Hangshuai Jin, Liwei Zhang, Yongxiu Song, Lei Liu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The modulation of peptide based nanostructure and the mechanical property is of significance in various areas, such as in biomaterial science, tissue engineering, etc. However, how to regulate the peptide based nanostructure from 1D to 2D and the mechanical property is rarely to explore. Herein, we constructed amphiphilic-like peptide (KFAK) to form nanostructure from 1D fibril to 2D sheet, and the nanomechanical properties changed during the modulation. The peptide based fibril was much stiffer than the peptide based nanosheet.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Weiteng Kong, Ke Zhao, Chunxia Gao, Peizhi Zhu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Layered carbonated hydroxyapatite (LCHA) was prepared by hydrothermal method under high concentration of carbonate ions. The crystallinity and chemical structure of synthesized LCHA with novel layer by layer structure was studied by Fourier transform infrared spectroscopy, X-ray diffraction, X-ray Photoelectron Spectroscopy and scanning electron microscopy. The biocompatibility and bioactivity of synthesized LCHA were determined by CCK-8 and Live/Dead staining assay. The experimental results show that synthesized LCHA with layer by layer structure has good biocompatibility and can promote cell growth.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Jun Liao, Keding Li, Yong Zhang, Lin Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The pure praseodymium oxide aerogel with ultra-low density (about 10.7 mg/cm〈sup〉3〈/sup〉) was prepared by using solution-freeze-drying-calcination method for the first time. The results of BET, SEM and TEM indicated that the pure praseodymium oxide aerogel belonged to the mesoporous material, which showed a typical three-dimensional porous structure. The results of TG/DSC showed that the praseodymium oxide aerogel could decrease the ammonium perchlorate decomposition temperature by 54.7 °C and enhance the heat production from 121.3 J/g to 838.5 J/g. The maximum adsorption amounts of praseodymium oxide aerogel reached 251.1 mg/g for uranium. This method provides a new strategy for preparation of low density metal oxide aerogels.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19310948-ga1.jpg" width="239" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Juyun Kim, Byoungnam Park〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We, for the first time, report fabrication of additive-free black phosphorous (BP) Li-ion battery without conductive agents and binders in which BP nanoflakes in solution are deposited using electrophoretic deposition (EPD). Addition of NaOH in pure 1-methyl-2-pyrrolidinone (NMP) solution containing BP nanoflakes facilitates the formation of smaller BP nanoflakes from bulk crystals allowing for the use as a battery anode. A remarkable increase in the initial discharging capacity from 91 to 954 mAh/g through simple treatments including the addition of NaOH followed by thermal annealing results from initiation of the multistep reactions associated with the formation of LiP, Li〈sub〉2〈/sub〉P, and Li〈sub〉3〈/sub〉P.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Mostafa M. Sayed, Hamouda M. Mousa, M.R. El-Aassar, Nehal M. El-Deeb, Nouby M Ghazaly, Montasser M. Dewidar, Abdalla Abdal-hay〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A biodegradable polyvinyl alcohol/silk fibroin (PVA/SF) nanofibrous heart patch with unique tensile properties was fabricated by an electrospinning technique based on a water-solvent system. The fabricated heart patches were exposed to 2% Glutaraldehyde vapor to provide a cross-linkage and tune the degradation behavior. Numerous characterizations of the modified PVA/SF patches such as surface morphology, chemical bonding, mechanical behavior, biodegradation, and biological assessment of the crosslinked PVA/SF patches were performed. It was found that pronounced and interconnected PVA/SF composite fibrous patches had an average nanofiber diameter of 228 ± 49 nm. In addition, incorporation of SF into PVA nanofibers enhanced the mechanical properties (i.e. tensile strength and tensile modulus) and tuning the degradation rate of the PVA/SF patch. Human cardiac fibroblast cells (HCFC) were cultured on the cross-linked composite patches and the results showed good cell proliferation and attachment on the patches bio-interface.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19311255-ga1.jpg" width="406" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Violetta Andreyachshenko〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The evolution of the aluminum alloy of the A3xx Al-Si-Mn-Fe series in the equal-channel angular pressing with back pressure with the strain of 0.75 per cycle has been carried out. After preliminary annealing dispersed inclusions of three types have been observed in the alloy: rod-like particles, planar-shaped rounded forms, and silicon particles. Two parallel grain refining schemes have been detected that ensure grinding the grains to the size of about 1 μm and smaller than 150 nm after the 1.5 degree of deformation. Three cycles of deformation lead to the appearance of small cracks in the sample, the destruction of the sample occurs at the total strain of 3.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19311140-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Sunjay Murali, Sreejith P. Madhusudanan, Amit K. Pathak, P.M. Jayasankar, Sudip K. Batabyal〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Organometallic halide perovskite as Methyl Ammonium Lead iodide (MAPbI〈sub〉3〈/sub〉) is the basis of current focus of solar energy materials research. Here we report acetophenone assisted pure phase MAPbI〈sub〉3〈/sub〉 powder crystals synthesis for fabrication of inexpensive self-powered photodetector. The as fabricated photodetector ascertain, response time of 200 ms with detectivity ∼8.2 × 10〈sup〉11〈/sup〉 jones at zero bias voltage and the SNR ∼4 × 10〈sup〉3〈/sup〉 under white light illumination intensity (19 mW/cm〈sup〉2〈/sup〉). Wt% variation of MAPbI〈sub〉3〈/sub〉 reveals that 20 wt% of the perovskite crystals in carbon matrix is better candidate for a compatible photodetector.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): YiDi Gao, JianPing Zhou, Yan Zhang, DaQian Sun, HongMei Li〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this work, TA2/Q235 was used as an composite interlayer to prevent the formation of these brittle Ti-Fe intermetallics when joining TC4 Ti alloy to 304 stainless steel (SS). The TA2/Q235 composite interlayer was prepared by explosive welding. The laser was focused on the TC4-TA2 interface, which joined the TC4 and TA2 by fusion welding. At TC4-TA2 interface, a weld zone was formed due to the mixing of molten TC4 and TA2. The laser was focused on the Q235-304 SS interface, a weld zone was formed due to the mixing of molten Q235 and 304 SS. Composite interlayer TA2/Q235 was used to prevent the formation of Ti-Fe intermetallics during welding and improve microstructure and properties of the Ti alloy-SS joint. The joint fractured at the TA2/Q235 explosive welding interface with the maximum tensile strength of 548 MPa.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Jing Li, Jianzhong Zhou, Aixin Feng, Xuliang Tian, Yu Huang, Shu Huang, Xiankai Meng〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this study, the effects of cryogenic laser peening (CLP) on mechanical properties and damping capacity of pure titanium (Ti) were explored. The experimental results showed that CLP improved the tensile properties and in-depth microhardness of pure Ti, while the compressive residual stress was introduced in the surface layer. Meanwhile, the damping ratio was also increased after CLP process. The synergistic strengthening effect of CLP could effectively accelerate the formation of deformation twin, which contributed to the simultaneous improvement in mechanical properties and damping capacity of pure Ti.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Junming Luo, Yuhai Chen, Linwei Zhang, Deping Lu, Jilin Xu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The modified layers were prepared on the GR2 titanium by plasma-pulsed detonation technology (PPD) in the compressed air (Air), argon (Ar) and nitrogen (N2) atmospheres, respectively. We observed that the modified layer was composed of TiN, TiN〈sub〉0.3〈/sub〉, Ti〈sub〉x〈/sub〉O〈sub〉y〈/sub〉 and Ti phases. The second phase strengthening, the fine grain strengthening and the dislocations strengthening are the main reasons for the improvement of wear resistance. Compared with the substrate, all modified layers have lower friction coefficient and better wear resistance. The wear volumes of three kinds of modified layers decrease by about 97%, 72% and 95%, respectively.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19311334-ga1.jpg" width="364" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): R. Senthil Kumar, T. Sarathi, K.K. Venkataraman, Amitava Bhattacharyya〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this study, for the first time we report the combined impact of electrospinning, carbon nanofiber (CNF) addition and electrical poling in the polyvinylidene fluoride (PVDF) polymer on its beta phase transition and enhancement of piezoelectric effect. CNF (0.25%, 0.5%, 0.75% and 1% (w/w)) dispersed PVDF electrospun nanofibers were characterized for their morphology, functional group and electrical properties using SEM, FTIR, Raman, XRD and impedance analyzer. The developed nanofibers showed promising results in beta phase transition and 0.5% (w/w) CNF filled PVDF nanofibers were found to possess high beta phase crystals compared to other studied samples. After 30 V/μm electrical polling at 30 °C for 6 h, piezoelectric property of 0.5% (w/w) CNF based nanocomposite nanofiber showed highest open circuit voltage and short circuit current (5.8 ± 0.17 V and 1.2 ± 0.1 µA, respectively, at 35 µm compression). In future, these matrices can be used for development of affordable and nontoxic energy converters in biomedical wearable sensors.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19311309-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): J. Wang, J. Zheng, S.T. Wang, J. Sun, Y.M. Guo, H. Wang, S.G. Huang, Y.D. Li, C.C. Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Organic dye contaminants are becoming a worldwide challenge for water resources due to their non-natural degradation, highly toxic and carcinogenic. In this work, the molecular ferroelectric material (MV)[BiI〈sub〉3〈/sub〉Cl〈sub〉2〈/sub〉] synthesized by the solvothermal method was first applied to the adsorption of organic dye contaminants. Interestingly, the adsorption capacity of the (MV)[BiI〈sub〉3〈/sub〉Cl〈sub〉2〈/sub〉] powder was found to reach a high value of 793 and 10,476 mg g〈sup〉−1〈/sup〉 for fluorescein sodium and Congo red, respectively. The adsorption process can be well described by the Langmuir model. It was argued that the electrostatic attraction, hydrogen bonding and π-π interaction might play a major role in the adsorption process.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Jingxuan Wang, Qu Zhou, Zhaorui Lu, Zhijie Wei, Wen Zeng〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Herein, we successfully prepared the Nickel oxide (NiO) nanomaterials with the structure of two-dimensional (2D) honeycomb-like nanoplates assembled by nanosheet arrays through the hydrothermal synthesis. In addition, the growth mechanism of this unusual nanostructure was proposed. Surprisingly, such NiO nanoplates exhibits superior gas-sensing properties to CO, which is mainly attributed to the hollow structure produced by the arrangement of nanosheets, contributing not only enough gases diffusion pathways but sufficient reaction sites during the gas sensing processes.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉 〈p〉The two-dimensional (2D) honeycomb-like nanoplates assembled by nanosheet arrays were synthesized using one-step hydrothermal method and the growth mechanism of this nanostructure was proposed. The sensor based on as-prepared NiO exhibits superior gas-sensing properties to CO. The results verified that the hollow structure of 2D nanoplates could enhance the gas sensing performance by providing sufficient gas diffusion pathways and reaction sites in the gas-sensitive process.〈/p〉 〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19311383-ga1.jpg" width="302" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): S.F. Chen, H.W. Song, S.H. Zhang, M. Cheng, M.G. Lee〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A novel severe plastic deformation process (SPD), namely an equal channel angular bending (ECAB), was proposed and successfully applied to thin Mg-3Al-1Zn sheets. Results of microstructure characterization indicate that simultaneous activation of multiple types of twins can be introduced by ECAB, which can refine the grain and efficiently weaken the basal texture. Moreover, the dominant twin types in ECAB are found to be closely related to the imposed deformation paths of ECAB, and profuse extension twinning can be activated under cross shear deformation. After appropriate annealing, the tensile ductility under cross shear deformation is improved with a relative increase of 60.5% to original sheets.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19311292-ga1.jpg" width="343" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Vini Singh〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Array based strategies on disposable screen printed electrodes (SPE) for detecting disease-specific biomarkers with high specificity and sensitivity are being explored as potential clinical diagnostic tools. Herein, we report the design of an electrochemical array with quantum dot (QD) decorated multi-walled carbon nanotube (MWNT) framework to perform the direct detection of multiple picomolar concentrations of insulin, an important biomarker for diagnosing diabetes, in physiological buffer.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Feng Mei Bai, Xin Ye, Hong Yan Zhang, Hong Wei Zhou, Meng Song, Ya Xin Sun, Yi Zhu He〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this work, a nanotwinned structure of a two-phase titanium (TC21) alloy was prepared via the martensitic phase transformation method. The TC21 alloy forms initially a single phase β when the temperature reaches 1050 °C. Then, it transitions into an orthorhombic martensite (α″) material when quenched in water. After tempering at 500 °C, the martensite transforms into a high-density nanotwinned α phase material. The hardness of the nanotwinned alloy is 25% higher than that of the TC21 raw material.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X1931122X-ga1.jpg" width="421" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Xiaofeng Liao, Hongqiang Li, Xuejun Lai, Wanjuan Chen, Xingrong Zeng〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Superhydrophobic materials with special functions such as electrical conductivity, magnetism and self-repairing have attracted considerable attention. Herein, a superhydrophobic conductive polydimethylsiloxane@silver nanowires (PDMS@AgNWs) cotton fabric was fabricated via a simple dipping-thermal curing method. Owing to the combination of rough structure constructed by AgNWs and the covered low-surface-energy PDMS, the as-fabricated cotton fabric exhibited superhydrophobicity with a high water contact angle (WCA) of 156°, and the separation efficiency for oil-water mixture reached 95.6%. Importantly, taking advantage of the excellent conductivity and electrothermal conversion performance, the functional cotton fabric was successfully applied in the fields of quick deicing under low temperature and piezoresistive sensing for human motion. Our findings stand out as a new tool to prepare functional superhydrophobic materials with electrical conductivity and electrothermal effect for various potential applications.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19311267-ga1.jpg" width="368" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): S. Huang, B.B. Wu, Z.Q. Wang, Y.S. Yu, C.S. Wang, L. Yan, X.C. Li, C.J. Shang, R.D.K. Misra〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Two high strength low alloy steels with different carbon content were studied to elucidate the effect of carbon content on hardenability in terms of crystallography. The hardness reduction from 2 to 50 mm distance from the surface in end-quenched steels of 0.09C and 0.12C was 8.0 and 3.2 HRC, respectively, which implied higher hardenability of 0.12C steel than 0.09C. At low cooling rate, the microstructure of 0.09C and 0.12C steel was granular and lath bainite, respectively, and the density of high angle grain boundaries (HAGBs) of 0.12C steel was significantly greater than 0.09C. Carbon improved the hardenability by optimizing the variant selection to increase the density of high angle grain boundary (HAGB).〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): S.M. Naga, H.F. El-Maghraby, M. Awaad, F. Kern, R. Gadow, A.M. Hassan〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The present study aims to prepare cerium hexaaluminate (CeAl〈sub〉11〈/sub〉O〈sub〉18〈/sub〉) via a sol-gel technique and to study the effect of the phase composition and microstructure on its mechanical properties. The samples were hot pressed at 1550 °C under a pressure of 40 MPa for 2 h. The apparent porosity and the relative density of the sintered samples were evaluated as well as their phase composition and microstructure. The results indicated that the only phase present in the densified bodies was the pure CeAl〈sub〉11〈/sub〉O〈sub〉18〈/sub〉 phase. The microstructure investigations indicated the presence of both cerium hexaaluminate and cerium monoaluminate (CeAlO〈sub〉3〈/sub〉) remnants. Both the Vickers hardness and bending strength of the sintered bodies were lower than those of pure alumina; however, the fracture toughness of the sintered bodies was high.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Rhushikesh Godbole, Sadia Ameen, Umesh T. Nakate, M. Shaheer Akhtar, Hyung-Shik Shin〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A quick and efficient approach was employed for the growth of nanocrystalline tungsten oxide (WO〈sub〉3〈/sub〉) thin films using one-step hot filament chemical vapor deposition (HFCVD) method at low temperature. In a typical experiment, the parent material tungsten (W) was subjected to oxidation, gasification and its subsequent condensation to obtain the uniform deposition of WO〈sub〉3〈/sub〉 thin film on silicon substrate at significantly low temperature of ∼200 °C. Prepared WO〈sub〉3〈/sub〉 thin film possessed the cauliflower nanostructure (WCNs) with typical monoclinic WO〈sub〉3〈/sub〉 crystal structure. Prepared WCNs thin films were applied for the detection of hydrogen (H〈sub〉2〈/sub〉) gas at 100 ppm. H〈sub〉2〈/sub〉 response increased with rise in temperature and the maximum response of ∼87% was obtained at the optimized temperature of ∼250 °C with response time 180 s.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Meng Guan, Yuhua Wang, Yongxian Huang, Xin Liu, Xiangchen Meng, Yuming Xie, Junchen Li〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Weld thinning has been an inherent issue of friction stir welding, which is detrimental to the joint integrity and mechanical properties especially for thin structures. In this paper, a novel method named non-weld-thinning friction stir welding was proposed. The welding tool contained an inner shoulder and an outer shoulder, and it was adjustable to control the protrusion of inner shoulder relative to outer shoulder. The outer shoulder could accumulate and refill the overflowing materials to eliminate weld thinning. The ultimate tensile strength reached 91% of base metal, which indicated that non-weld-thinning friction stir welding had the feasible and potential to realize high quality joint without weld thinning.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Elena V. Bobruk, Zarema A. Safargalina, Oleg V. Golubev, Danil Baykov, Vil U. Kazykhanov〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this study the ultrafine-grained aluminum alloy 6061 of the Al-Mg-Si system with a grain size of 350 nm and a regulated distribution of the secondary hardening phase Mg〈sub〉2〈/sub〉Si, processed by equal-channel angular pressing in parallel channels (ECAP-PC), was investigated. Under tensile stress at 160⋯250 °C, this ultrafine-grained structure gives rise to signs of superplastic behavior at lower temperature with a total elongation of 240%, the parameter of strain rate sensitivity (〈em〉m〈/em〉) equals to 0.31. The forming behavior of ultrafine-grained alloy 6061 at room temperature was studied by Eriksen test method, which is a simulation of cold sheet stamping.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Qinghua Yang, Limei Xu, Shiting Luo, Meifeng Chen, Xiaolang Wang, Lin Ma〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A one-pot hydrothermal followed by annealing route has been developed to prepare ZnS/C microspheres which are comprised of ZnS nanoparticles incorporated with 〈em〉in-situ〈/em〉 gluconate-derived carbon. The robust hybrid structure greatly enhances the stability and conductivity of composites. As a result, the great enhancement in electrochemical Li-storage of ZnS/C can be achieved due to the desirable structural features as well as capacitive contribution.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉 〈p〉SEM image and cycling performance of ZnS/C microspheres.〈/p〉 〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X1931081X-ga1.jpg" width="251" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Anas Lataifeh, Heinz-Bernhard Kraatz〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We report a facile method to modify the surface of silver nanoparticles (AgNPs) by peptide dendrimers terminated with carboxylic acid (COOH) groups. This conjugate displays a tendency to self-assemble along the path of cationic poly-〈em〉L〈/em〉-lysine (PLL) supramolecule. The resulting “neckless” superstructure is confirmed by transmission electron microscopy (TEM).〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19310808-ga1.jpg" width="266" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Quang Duc Truong, Thanh Son Le, Thu H. Hoa〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Crystalline ultrathin TiO〈sub〉2〈/sub〉 nanowires with oriented configurations are promising for high-performance energy storage and conversion devices. In this work, we use hierarchical microspheres constructed from radially oriented single-crystalline TiO〈sub〉2〈/sub〉 nanowires as electrode materials for reversible Mg-ion intercalation. The obtained mesoporous TiO〈sub〉2〈/sub〉 nanowires deliver a capacity of 118 mA h g〈sup〉−1〈/sup〉 at 20 mA/g current rate. The ultra small size of TiO〈sub〉2〈/sub〉 nanocrystalline is beneficial for reaction kinetics, enhance the bulk intercalation of Mg ions, which remarkably increases storage capacity of TiO〈sub〉2〈/sub〉. The discharge capacity over 100 cycles remains 105.2 mA h g〈sup〉−1〈/sup〉, demonstrating the superiority of this material structure and its potential in magnesium ion batteries.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X1931095X-ga1.jpg" width="267" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Lu Qi, An Xie, Tianjiang Chen, Jie Han, Lei Yu, Ming Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A novel emulsion polymerization-extraction method was developed to synthesize polyanilines (PANIs). Compared with reported works, this method could prepare the xylene solution of PANIs directly with significantly enhanced concentration (24.08–64.50 g/L in this work vs. 3.83 g/L in reference), facilitating the preparation of uniform PANIs/poly(styrene-ethylene-butadienestyrene) (SEBS) mixtures to make the PANIs/SEBS conductive films. The as-prepared PANIs/SEBS films possessed as good conductivities as the reference reports (4.9 × 10〈sup〉−5〈/sup〉–9.3 × 10〈sup〉−2〈/sup〉 S/cm in this work vs. 10〈sup〉−5〈/sup〉–10〈sup〉−4〈/sup〉 S/cm in reference), and might be widely applied as flexible conductive materials in fabrication of some critical components (e.g. wearable devices) in electronic industry.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19310985-ga1.jpg" width="433" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Yu Wang, Fangyu Gan, Kanghua Chen〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The use of rare metals as current collectors in aluminum-ion batteries is an urgent problem to be solved, so there are significant interests in the development of light-weight and high-efficiency materials as current collector. Herein, we report a polyvinyl-alcohol/graphene composite film as current collector in aluminum-ion batteries which synthesized by a simple solution method. The film containing 20 wt% graphene demonstrates high electrical conductivity up to 164S·cm〈sup〉−1〈/sup〉 with ∼30 μm in thicknesses and 2.8 mg cm〈sup〉−2〈/sup〉 in areal density. According to the electrochemical measurements, a reversible capacity of 89 mAh g〈sup〉−1〈/sup〉 is obtained at a rate of 1C in aluminum-graphite battery.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19309528-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Xuehua Zhang, Yongqing Zhao, Weidong Zeng〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The hot deformation behavior of Ti-6Al-4V alloy was investigated by isothermal compression tests carried out in the 1083–1173 K temperature range and 0.01–10 s〈sup〉−1〈/sup〉 strain rate regime. The effect of temperature and strain rate on the flow stress of this alloy was evaluated, and, the constitutive equation was obtained, which could well predict the flow stress. Furthermore, the microstructure evolution was investigated, it was also found that the elongated primary α and secondary α grains became equiaxed through suitable treatment, where the deformation mechanism was dynamic recrystallization.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Seyedeh Marjan Bararpour, Hamed Jamshidi Aval, Roohollah Jamaati〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The present study for the first time demonstrates that friction surfacing can be applied as a process of mechanical alloying. The Zn powder was added to the coating through insertion of the hole in the consumable AA5083 rod. Zn dissolution and production of a solid solution during friction surfacing confirmed by X-ray diffraction. The results showed a solid solution, which was formed during friction surfacing and decomposed due to artificial aging, resulting in the formation of AlMg〈sub〉4〈/sub〉Zn〈sub〉11〈/sub〉 precipitates. Moreover, abnormal grain growth was observed in the coating after solid solution and aging treatment.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19310997-ga1.jpg" width="296" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Peng Peng〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The influence of radial convection on the microstructure development has been investigated in directionally solidified Sn-36at.%Ni peritectic alloys at a constant growth velocity with different sample diameters. Since the rejected Sn is denser than Ni, there existed no axial convection in directionally solidified Sn-36at.%Ni peritectic alloys, however, the radial convection still influenced the microstructures. It was demonstrated through the dendrite tip radius R that the diffusive growth condition could be obtained in this alloy when the sample diameter was reduced to 1 mm. Furthermore, it was confirmed that the radial convection could obviously promote the peritectic transformation process in Sn-Ni peritectic alloy.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Xiaojing Xu, Qiang Mao, Ze Jiang, Tabie Vitus, Tianci Zhang, Weijie Jia, Chengyu Zhu, Hao Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The aluminum alloy extrusion materials were treated by multi-stage solution aging, and the microstructure and mechanical properties were characterized and tested. The results show that with the increase in solid solution temperature and time, the strength shows a trend of increasing first and then decreasing, and reaches a maximum value in G3. Under the conditions of 450 °C × 2 h + 460 °C × 2 h + 470 °C × 2 h in solid solution process and 121 °C × 5 h + 133 °C × 16 h in the aging process, the aluminum alloy has excellent comprehensive properties, with a strength of 828.0 MPa and elongation of 8.1%.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Nanthini Amirthalingam, Thenmuhil Deivarajan, Manohar Paramasivam〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Hydroxyapatite was prepared by mechano chemical method using dolomite as a calcium source for the first time, and the effect of temperature from 950 °C to 1250 °C was studied. The prepared powder was characterized by X-ray diffraction (XRD) analysis which confirmed formed of HAp by 950 °C and its decomposition to form other phases like β-TCP and monetite above 1050 °C. Thermal analysis by TGA, Morphology and composition analysis by SEM-EDX, loss on ignition and hardness were also measured.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Kai Xu, Xiaohong Chen, Honglei Zhou, Liming Bi, Shaoli Fu, Wei Li, Xinkuan Liu, Fengcang Ma, Ke Zhang, Ping Liu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉CNTs/Cu-Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 composite powders were successfully synthesized by 〈em〉in situ〈/em〉 CVD using Cu-Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 composite powders obtained by internal oxidation of Cu-Al alloy powders. The multi-walled CNTs are obtained without agglomeration and stand on the surface of the composite powders. One end of the CNTs is well bound to matrix. The Cu nanoparticle was the catalyst for the growth of CNTs on the composite powders and Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 on the surface of the Cu-Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 powder plays a key role in the growth process.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Hisham Aboulfadl, Frank Mücklich〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The microstructure properties of reactive multilayers play a key role in their chemical reactions. Ru/Al multilayers are investigated in as-deposited and annealed conditions using atom probe tomography to probe the interdiffusion and early phase formation. Performing atom probe analysis was accompanied with difficulties stemming from weak adhesion of the bi-layers and reconstruction artifacts. Nonetheless, it was possible to obtain valuable qualitative information concerning diffusion kinetics. Asymmetric interdiffusion during deposition is found. Grain boundary diffusion is shown to have a major contribution on enhancing mass-transport across the layers as well as on the nucleation and growth of the RuAl〈sub〉6〈/sub〉 intermetallic phase.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Tian Chen, Fangzhou Lu, Kai Xiang, Yanni Wang, Liwen Deng〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this study, we prepared a host-guest (H-G) complex containing graphene (Gp) by utilizing the H-G supramolecular force of cyclodextrin (Cd) and azobenzene (Ab). Then we synthesized a conductive composite (CC) by using Gp-Cd-Ab H-G complex. Fourier transform infrared spectroscopy (FT-IR) of CC confirmed the presence of H-G supramolecular assemblies. Electrochemical impedance spectroscopy (EIS) showed CC had smaller bulk resistance. The tensile curves showed CC had larger Young’s modulus. CC had the properties of conductive and mechanical self-healing. CC also showed strain sensing performance. Thus the composite showed potential application in healable soft sensor.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 254〈/p〉 〈p〉Author(s): Yang Wang, Zhihao Rong, Xincun Tang, Shan Cao, Xi Chen, Wei Dang, Liping Wu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Leaching liquid of smelting dust was used as the As(∨) source. Common octahedral-shaped scorodite and large spindle-shaped scorodite were synthesized. Through the analysis, the high concentration H〈sup〉+〈/sup〉 can inhibit the forming and growth of (1 1 1) and (2 0 0) lattice planes. The particles aggregated together and assessed during the ageing process. The large high crystallinity spindle-shaped scorodite was formed at last. TCLP tests at pH 4.93 and leaching tests were carried out in alkaline solutions with pH of 9.30. Large spindle-shaped scorodite materials have better stability than the common octahedral-shaped scorodite.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Ruiyu Han, Jing Ma, Chaoju Yang, Tong Cui, Wenjiao Liu, Shusong Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this work, nitrogen-doped carbon nanocages were prepared for uric acid detection, which exhibits three dimensional hollow nanostructures with large specific surface area of 565 m〈sup〉2〈/sup〉 g〈sup〉−1〈/sup〉 and unique heteroatomic property. The as-synthesized nitrogen-doped carbon nanocages show high selectivity and sensitivity for uric acid detection accompanied with excellent stability. The developed electrochemical analysis for facile determination of uric acid shown a wide linear range of 0–1.0 mM, with the detection limit of 2.07 × 10〈sup〉−2〈/sup〉 μM (S/N = 3). Moreover, this strategy was successfully used for uric acid detection in human serum and urine samples and demonstrated satisfied recoveries. The result in the present work suggests that nitrogen-doped carbon nanocages hold great potential to use as superior electrochemical sensors for uric acid determination.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): S.O. Rogachev, V.M. Khatkevich, S.A. Nikulin, M.V. Ignateva, A.A. Gromov〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A comparative analysis of the thermal stability of the steel/vanadium alloy hybrid material and its components (steel type AISI 439 and V–10Ti–5Cr alloy) obtained by high-pressure torsion (HPT) at 20 and 400 °C was carried out. It has been established that the steel/vanadium alloy hybrid obtained by HPT at 20 °C has a higher thermal stability up to a temperature of 700 °C compared to the hybrid obtained by HPT at 400 °C and with hybrid components (steel and vanadium alloy) after HPT at 20 and 400 °C, the thermal stability of which does not exceed 400–450 °C.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): HuJun Xu, ChaoHong He, LiangLiang Lin, Jie Shen, ShaoMing Shang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A conceptually new method based on plasma-electrochemical technique is demonstrated for the one-step synthesis of carbon supported Pt nanoparticles. Ethanol and chloroplatinic acid aqueous solution were used as the carbon and platinum sources, respectively, without involving any extra chemicals. Results showed that crystalline Pt nanoparticles as well as amorphous nanocarbons could be simultaneously generated to form Pt/C nanocomposites under the plasma impact, where the Pt content can be tuned by regulating the chloroplatinic acid concentration. Moreover, the formation mechanisms of the C and Pt/C nanocomposites in the studied system were discussed. The demonstrated simple, unique, one-pot and environmentally-benign process should bring interest in this emerging nanofabrication technique.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19311474-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Xin Li, Jin Zhang, Wanling Shen, Shutao Xu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉MIL-53(Cr) is a well-known and important metal-organic framework material. However, the long synthesis time of MIL-53(Cr) restricts its applications. Herein, we report a facile method to kinetically modulate the crystallization route and decrease the synthesis time of 72 to only 8 h by simply increasing the usage of HF.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19311346-ga1.jpg" width="423" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Francisco W.A. Bezerra, Lillian M.U.D. Fechine, Karen P.S. Lopes, Anderson F. de Sousa, Gerlan O. do Nascimento, Hilmara H. de S. Amaral, Luzia K.A.M. Leal, Maria T.S. Trevisan, Maria E.N.P. Ribeiro, Nágila M.P.S. Ricardo〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Mangiferin-loaded F127/PEG micellar systems were evaluated regarding the effect of PEG addition at different molecular weights, where the system with best mangiferin solubility response (0.5 wt% of PEG in 1 wt% F127 aqueous solution) was chosen to be a potential drug delivery system (DDS), which solubilized 7.92 mg dL〈sup〉−1〈/sup〉 of mangiferin. Subsequently, the chosen mangiferin-loaded DDS was evaluated in regard the inhibition of enzyme α-glucosidase, which showed a more effective inhibition, around 95.42%, when compared to the standard acarbose (92.59%) and to the free-form mangiferin (90.42%). The same micellar system was also evaluated for its cytotoxicity, where no significative values of LDH activity was observed. No study has been done yet with both mangiferin and DDSs regarding 〈em〉in vitro〈/em〉 α-glucosidase inhibitory activity. This work proposes a “new” alternative towards diabetes treatment.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19311371-ga1.jpg" width="294" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Gregory Gerstein, Franz Körkemeyer, Andrej Dalinger, Stefan Zaefferer, Hans Jürgen Maier〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Electroplasticity has been explained by increased glide due to electron dislocation interactions and thermal effects. However, current pulse treatment of AZ 31 at 0.7 kA mm〈sup〉−1〈/sup〉 within the elastic regime caused significant twinning, occurring in thin bands in the interior of grains. This is inconsistent with a purely dislocation based explanation of electroplasticity, which predicts a suppression of twinning as a strain accommodation mechanism. The presence of unexpected twinning offers insights on the relative contributions of dislocation mediated mechanisms and contributions from Joule heating to the overall effect.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19311310-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 255〈/p〉 〈p〉Author(s): Haoran Cai, Xiaolong Li, Geng Li, Hanchun Xia, Peijia Wang, Peiheng Sun, Jiajie Huang, Liang Wang, Yefeng Yang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Honeycomb-like nickel-manganese sulfide (NMS) composite nanosheets have been grown on carbon cloth. The optimized NMS composite exhibits a high specific capacity of 205 mAh g〈sup〉−1〈/sup〉 at 2 mA cm〈sup〉−2〈/sup〉 with good rate capability of 78% at 20 mA cm〈sup〉−2〈/sup〉. The hybrid supercapacitor based on NMS composite obtains a maximum energy density of 27.3 Wh kg〈sup〉−1〈/sup〉 at a power density of 505.2 W kg〈sup〉−1〈/sup〉 with excellent cycling stability of 75.3% over 6000 cycles at 8 mA cm〈sup〉−2〈/sup〉.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19311206-ga1.jpg" width="297" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): Jinyan Dai, Jiejie Li, Qunbin Zhang, Min Liao, Tao Duan, Weitang Yao〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Transition metal chalcogenides as a promising anode material with high theoretical capacity has attracted more and more attention. This thesis focuses on a facile method to synthesize hollow Co〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 encapsulated by carbon layers (Co〈sub〉3〈/sub〉O〈sub〉4〈/sub〉@C) with polydopamine as precursor, after reacting with thioacetamide and (NH〈sub〉4〈/sub〉)〈sub〉6〈/sub〉Mo〈sub〉7〈/sub〉O〈sub〉24〈/sub〉·4H〈sub〉2〈/sub〉O, hollow rhombic dodecahedral shape Co〈sub〉3〈/sub〉S〈sub〉4〈/sub〉@C@MoS〈sub〉2〈/sub〉 heterostructures are successfully fabricated and employed as the anode of lithium-ion battery. Benefiting from the typical layered structure of Co〈sub〉3〈/sub〉S〈sub〉4〈/sub〉@C@MoS〈sub〉2〈/sub〉 heterostructures, the stability and capacity have been significantly improved, with a high capacity of 672.6 mAh g〈sup〉−1〈/sup〉 after 200 cycles at the current density of 0.2 A g〈sup〉−1〈/sup〉. The excellent electrochemical properties of hollow Co〈sub〉3〈/sub〉S〈sub〉4〈/sub〉@C@MoS〈sub〉2〈/sub〉 heterostructures are ascribed to the consolidate of Co〈sub〉3〈/sub〉S〈sub〉4〈/sub〉, carbon and MoS〈sub〉2〈/sub〉, and the stability of the composite structure.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉 〈p〉Structural representation, cycling stability and corresponding Coulombic efficiency of Co〈sub〉3〈/sub〉S〈sub〉4〈/sub〉@C@MoS〈sub〉2〈/sub〉 and Co〈sub〉3〈/sub〉S〈sub〉4〈/sub〉@MoS〈sub〉2〈/sub〉 at 0.2 A/g.〈/p〉 〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X18317464-ga1.jpg" width="432" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): Deepika Divakaran, Jaya R. Lakkakula, Mukeshchand Thakur, Mukesh Kumar Kumawat, Rohit Srivastava〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Biosynthesis of gold nanoparticles from Dragon fruit extract (DF extract) can be considered as an eco-friendly alternative for synthesis of gold nanoparticles. The aim of this study was to investigate the ability of this fruit to synthesize gold nanoparticles and to study its anticancer activity. The as synthesized gold nanoparticles were characterized by UV-vis spectrophotometry, X-ray diffraction, Fourier Transform Infra-red spectroscopy and Transmission Electron microscopy. The results from XRD and TEM support the biosynthesis of DF extract capped gold nanoparticles (DF-AuNPs) in the size range of 10–20 nm. The DF extract and DF-AuNPs induced significant growth inhibition of MCF-7 breast cancer cells however, no significant toxicity effect was observed on MDA-MB-231 cells.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X18317361-ga1.jpg" width="321" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): K.M. Zhu, S.Y. Ma〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In order to improve the gas sensing performance of traditional SnO〈sub〉2〈/sub〉 semiconductor nanomaterials, Bi-doped SnO〈sub〉2〈/sub〉 hierarchical flower-shaped nanostructures had been synthesized by a one-step hydrothermal route. Diverse techniques characterization results collectively revealed that Bi ions have been successfully doped into SnO〈sub〉2〈/sub〉 lattice and samples present numerous uniform flower-shaped nanostructures composed of many layered petal-like thin nanosheets. Benefiting from such unique 3D hierarchical flower-shaped nanostructures and Bi doping, the sensors based on Bi-doped SnO〈sub〉2〈/sub〉 exhibited superior gas sensing performance concluding higher response value, faster response/recovery time, good stability and excellent selectivity to HCHO at the optimum operating temperature of 170 °C. Therefore, Bi-doped SnO〈sub〉2〈/sub〉 hierarchical flower-shaped nanostructures could be used as a candidate semiconductor gas sensing materials for manufacturing highly sensitive HCHO gas sensors in the future.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): Qian Ma, Shushu Chu, Yu Liu, Ying Chen, Junchao Song, Hui Li, Junpeng Wang, Quande Che, Gang Wang, Yuan Fang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉SnO〈sub〉2〈/sub〉-based flower-like sensitive materials derived from the self-assembled SnS〈sub〉2〈/sub〉 microstructures with more active areas and less agglomeration represent an alternative option for new generation of gas sensors. Meanwhile, the introduction of ZIF-8 for semiconductor surface functionalization is expected to get multi-functional hybrid materials with synergistic effects of individual components. In the present work, SnS〈sub〉2〈/sub〉/ZIF-8 derived porous flower-like SnO〈sub〉2〈/sub〉/ZnO heterostructures have been synthesized by a facile template method and the subsequent heat-treatment process. Beside the uniform morphology with tunable composition and size distribution, the attractive findings are focused on the enhanced triethylamine (TEA) gas-sensing properties of the obtained composites. SnO〈sub〉2〈/sub〉/ZnO heterostructures show an obvious improvement in TEA gas sensing performance at the operating temperature of 200 °C, giving a response of about 17.7–50 ppm TEA, which was about 2.2 times higher than that of the sensors based on pure SnO〈sub〉2〈/sub〉.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X18317282-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): Nikhil Shajan, Kanwer Singh Arora, Mahadev Shome〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Flash butt welds show variation in impact toughness from the fusion line (FL) to the parent material (PM). A direct correlation of the variation in toughness, (1 1 0)[0 0 1] Goss texture and grain boundary misorientation fractions were observed. PM texture transformed to Goss, rotated Goss and rotated cube components in the thermo-mechanically affected zone (TMAZ) due to the shear deformation experienced during the upsetting stage. Whereas in the heat affected zone (HAZ) adjacent to TMAZ only microstructural changes were observed〈sub〉.〈/sub〉 Formation of (1 1 0)[0 0 1] texture component, higher fraction of Low Angle Grain Boundaries (LABs) as a result of deformation close to FL resulted in deterioration of toughness.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 235〈/p〉 〈p〉Author(s): R.S. Nascimento, B.A.M. Figueira, L.N. da Silva, P. Callejas, G.C. Telles, T.C. Lavra, J.M.R. Mercury〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this work, nanopyroaurite was successfully obtained from bauxite-mining residues via co-precipitation and hydrothermal synthesis. The effect of crystallization time and temperature on the formation of layered-type material were investigated. The product was characterized by XRD, FT-IR, Raman spectroscopy and HR-TEM with EDS analysis. The results revealed that bauxite residues could be transformed into aggregate nanoparticles with nanosizes around 50–60 nm, confirming the residues as raw material for the synthesis of nanomaterial.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 235〈/p〉 〈p〉Author(s): V.A. Khomchenko, M.S. Ivanov, D.V. Karpinsky, S.V. Dubkov, M.V. Silibin, J.A. Paixão〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this paper, we report on the crystal structure, magnetic and local ferroelectric properties of the Bi〈sub〉1−x〈/sub〉Ca〈sub〉x〈/sub〉Fe〈sub〉1−x/2〈/sub〉Nb〈sub〉x/2〈/sub〉O〈sub〉3〈/sub〉 (〈em〉x〈/em〉 ≤ 0.2) compounds prepared by a solid state reaction method. The chemical substitution has been found to reduce the polar ionic displacements in the acentric 〈em〉R3c〈/em〉 structure and give rise to the formation of the non-polar 〈em〉Pnma〈/em〉 phase at 〈em〉x〈/em〉 = 0.2. The substitution-driven decrease of spontaneous polarization is accompanied by the suppression of the cycloidal antiferromagnetic order specific to the parent BiFeO〈sub〉3〈/sub〉. As a result, a weak ferromagnetic and ferroelectric state is formed at 〈em〉x〈/em〉 ≈ 0.18. Lattice defects contribute to the instability of the cycloidal structure, thus providing the antiferromagnetic + weak ferromagnetic phase coexistence observed over a wide range of Ca/Nb concentrations.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): Lilong Du, Wen Li, Zhuyan Jiang, Lianyong Wang, Deling Kong, Baoshan Xu, Meifeng Zhu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Scaffolds with hierarchical structures capable of promoting cells attachment, proliferation and guiding tissue formation have always been one of the major goals in tissue engineering. Here, a macro/micro-porous silk fibroin (SF) scaffold was fabricated by combining the paraffin sphere leaching and phase separation methods. The scaffolds possess adjustable macro/micro pores size, interconnected pores, high porosity and certain mechanical property. The scaffolds also promoted cell attachment, infiltration and proliferation, which can be an ideal candidate for cell delivery and tissue regeneration.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 235〈/p〉 〈p〉Author(s): F.B. Moreno-Luna, A. Tovar-Corona, J.L. Herrera-Perez, J. Santoyo-Salazar, E. Rubio-Rosas, O. Vázquez-Cuchillo〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Gold nanoparticles were synthetized in short time by a novel and easy method by using an aqueous extract from 〈em〉Agave potatorum〈/em〉. The UV–Vis data show a characteristic band at 540 nm, from the minute 2 of synthesis that intensifies through the reaction time advances, by X-Ray diffraction and Selected Area Electron Diffraction (SAED), it is demonstrated the polycrystallinity of the samples, exhibiting the specific features of metallic gold; the Transmission Electron Microscopy (TEM) results show pseudospherical nanoparticles with an average size of 14 nm corresponding to the synthesized samples at 10 min and 22 nm in the case of the synthesized samples at 20 min. The results suggest that the Agave extract works also as stabilizer.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X18315118-ga1.jpg" width="295" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): P. Vijaya Kumar, S. Mary Jelastin Kala, K.S. Prakash〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A simple one-pot green approach for the biosynthesis of gold nanoparticles (AuNPs) by reducing chloroauric acid (HAuCl〈sub〉4〈/sub〉) with extract of 〈em〉Croton Caudatus Geisel〈/em〉 is described. The synthesized new gold nanoparticles were extensively characterized by UV Visible spectroscopy, FT-IR, XRD, SEM-EDAX and TEM analysis. The size, shape and purity were analyzed. The biological profile such as 〈em〉In vitro〈/em〉 cytotoxicity activity, 〈em〉In vitro〈/em〉 antimicrobial activity, Free radical scavenging ability and 〈em〉In vitro〈/em〉 antifungal activity were investigated and shows the significance of their application towards biological activity.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X1831588X-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): J.L. Amorós, E. Blasco, A. Moreno, E. Zumaquero, C. Feliu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This report sets out the results obtained on studying the sintering process of glass–zircon composites, analysing the microstructural changes that developed on modifying zircon content. The sintering of composites with moderate zircon contents only developed via particle rearrangement by viscous flow. In contrast, at high zircon contents, the zircon solution–reprecipitation process was also required. A kinetic model was developed and validated that describes the effect of the heating rate and zircon volume fraction on the composite degree of non-isothermal sintering progress associated with particle rearrangement by viscous flow.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): Peter Wagner, Oliver Schwarzhaupt, Michael May〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In-situ X-ray computed tomography and online stiffness monitoring were used to study damage initiation and propagation in multi-directional carbon fiber reinforced composite coupon subjected to tension-tension fatigue loading. It was found that a resolution of the CT system of 8 µm was sufficient to capture matrix crack inside the specimen. A clear correlation was found between the increasing number of matrix cracks and the observed stiffness degradation of the composite specimen.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 235〈/p〉 〈p〉Author(s): Zili Wu, Xiong Zhang, Aijie Fan, Hu Chen, Jianguo Zhao, Shuai Chen, Shuchang Wang, Yiping Cui〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The nonpolar 〈em〉a〈/em〉-plane Mg-doped p-type AlGaN/GaN distributed Bragg reflectors (DBRs) were grown for the first time with metal organic chemical vapor deposition technology. The structural, optical, and electrical properties of the nonpolar p-DBRs were characterized with various kinds of technical tools. The measurement results demonstrate that a stopband centered at 390 nm with a peak reflectivity of 55% was achieved. Meanwhile, a relatively high reflectivity (〉35%) could also be obtained within the wavelength range of 270–320 nm for the nonpolar p-DBR which was intended to be a reflector with a working wavelength at 280 nm. Additionally, a hole concentration higher than 2 × 10〈sup〉17〈/sup〉 cm〈sup〉−3〈/sup〉 was obtained with the nonpolar p-DBRs.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): Jinzhu Wu, Lixin Du, Yanbin Shao, Xiaohong Wu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Molybdenum disulfide (MoS〈sub〉2〈/sub〉) holds promise as an electrocatalyst candidate for hydrogen evolution reaction (HER). However, it is a challenge for MoS〈sub〉2〈/sub〉 electrocatalyst to owe simultaneously good electrocatalytic activity and long-term electrochemical stability. Herein, we synthesize MoS〈sub〉2〈/sub〉 by a hydrothermal method with the assistance of silicon quantum dots (SiQDs). The resultant SiQDs-MoS〈sub〉2〈/sub〉 possesses a 3D framework structure with dense mesoporous whilst contains 1T and 2H phases. Consequently, SiQDs-MoS〈sub〉2〈/sub〉 elecctrocatalyst presents good electrocatalytic activity (overpotential of 200 mV and Tafel slope of 60 mV dec〈sup〉−1〈/sup〉) and acceptable electrochemical stability (72 h). Integration of the mesoporous 3D structure and the 1T/2H multiphase can contribute to the excellent electrocatalytic performance. This work provides insights into the design and development of the high-performance electrocatalysts.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 235〈/p〉 〈p〉Author(s): Biny R. Wiston, M. Ashok〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Nickel hydroxide and nickel oxide were prepared via a facile chemical precipitation method, whose structure, morphology and electrochemical properties were compared. Nickel hydroxide demonstrated nanopetal-like morphology, pseudocapacitive nature, a superior specific capacitance of 701 F g〈sup〉−1〈/sup〉 at 1 A g〈sup〉−1〈/sup〉 and admirable capacitance retention of 84.16% even after 5000 consecutive charge–discharge cycles in 2 M KOH aqueous electrolyte. Meanwhile, nickel oxide grew into a cluster of randomly shaped nanostructures with pseudocapacitive behavior and comparatively lower specific capacitance of 171 F g〈sup〉−1〈/sup〉 at 1 A g〈sup〉−1〈/sup〉. In nickel hydroxide, the freedom of movement of electrolyte ions is responsible for its loftier charge storage capability.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 235〈/p〉 〈p〉Author(s): M. Krishnakumar, S. Karthick, G. Vinitha, K. Thirupugalmani, B. Babu, S. Brahadeeswaran〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Single crystals of 2-Amino pyridinium-4-hydroxy benzoate (2AP4HB) have been successfully grown by controlled slow evaporation technique. The title compound was synthesized and single crystals were harvested utilizing methanol as a solvent. The crystalline structure and crystal phase studies were carried out by single crystal and powder X-ray diffraction techniques respectively. UV–Vis transmission plot was traced and band gap value has been calculated for the title compound. Laser induced damage threshold (LIDT) analysis of 2AP4HB single crystal has been performed employing 1064 nm wavelength Nd:YAG laser. Third order nonlinear optical (NLO) efficiency of grown 2AP4HP single crystals was probed using Z-Scan technique. Optical limiting study of 2AP4HB was carried out using continuous wave (cw) Nd:YAG laser to reveal its saturable absorption behavior and self-defocusing effect.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): I. Batko, M. Batkova〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We argue that the ground state energy distribution function of the subsystem of localized charge carriers in valence fluctuating semiconductors is qualitatively different from that for conventional semiconductors at 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si5.gif" overflow="scroll"〉〈mrow〉〈mi〉T〈/mi〉〈mo〉=〈/mo〉〈mn〉0〈/mn〉〈/mrow〉〈/math〉 K. As follows from our analysis, both occupied and unoccupied sites can be found above as well as below the Fermi level in the ground state as a consequence of dynamical changes of impurity energies due to valence fluctuations. Such anomalous energy distribution of charge carriers sheds new light on interpretation of experimental results of valence fluctuating semiconductors, e.g. SmB〈sub〉6〈/sub〉 and YbB〈sub〉12〈/sub〉.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 235〈/p〉 〈p〉Author(s): H.L. Ge, J.D. Liu, S.J. Zheng, Y.T. Zhou, Q.Q. Jin, X.H. Shao, B. Zhang, Y.Z. Zhou, X.L. Ma〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Generally, minor elements such as carbon and boron are added in superalloys to strengthen grain boundaries. However, effects of carbon and boron on single crystal superalloys remain disputed. Here we demonstrate that M〈sub〉23〈/sub〉B〈sub〉6〈/sub〉 (where M is mixture of W, Mo, Cr and Ni) can induce dislocation channeling in a Ni-based single crystal superalloy. The M〈sub〉23〈/sub〉B〈sub〉6〈/sub〉 has a cube-on-cube orientation relationship with the matrix, forming a majority of {1 1 1} plane interfaces. Furthermore, the atomic stepped {1 1 1} interface could facilitate dislocation nucleation. Dislocations emitted from the interface glide forward and pile-up in the channel, resulting in strain localization and creep micro-crack initiation.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X18315866-ga1.jpg" width="489" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): N. Haberkorn, S. Bengio, S. Suárez, P.D. Pérez, J.A. Hofer, M. Sirena〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We report on the influence of the disorder and stoichiometry in the resulting superconducting critical temperature of γ-Mo〈sub〉2〈/sub〉N thin films. Initially, three films (with 〈em〉T〈sub〉c〈/sub〉〈/em〉 values of 7.6 K, 6.8 K and 6 K) were grown at room temperature by reactive sputtering, on Si (1 0 0) using different N〈sub〉2〈/sub〉/(Ar+N〈sub〉2〈/sub〉) mixtures. The influence of the thermal annealing up to 973 K and irradiation damage produced by 1 MeV Zr〈sup〉+〈/sup〉(fluence up 2 × 10〈sup〉14〈/sup〉 cm〈sup〉−2〈/sup〉) is analyzed. The 〈em〉T〈sub〉c〈/sub〉〈/em〉 of pristine films remains unchanged for increasing irradiation doses up 2 × 10〈sup〉14〈/sup〉 cm〈sup〉−2〈/sup〉. The 〈em〉T〈sub〉c〈/sub〉〈/em〉 for annealed films decreases close to the value expected for bulk samples (≈5 K) for increasing the annealing temperature. Successive irradiations of the annealed films tend to increase their 〈em〉T〈sub〉c〈/sub〉〈/em〉 up to its initial values (before annealing). The results indicate that the 〈em〉T〈sub〉c〈/sub〉〈/em〉 in nanometric grain size γ-Mo〈sub〉2〈/sub〉N thin films is affected by both nitrogen stoichiometry and disorder at the atomic scale.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 235〈/p〉 〈p〉Author(s): Bin Zhao, Xiaoyuan Zhang, Xianzhu Fu, Conor McCarthy〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 hollow nanospheres-carbon nanotubes (Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 HNSs-CNTs) nanocomposites were synthesized under one-pot solvothermal treatment. The crystalline structure, size and morphology of the composite products are characterized by XRD, SEM and TEM, indicating that Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 HNSs are tightly wrapped by CNTs with a good distribution. The products were dispersed in silicone oil for evaluating the dielectric heating performance under microwave irradiation. The Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 HNSs-CNTs nanocomposite (mass ratio 1:9) exhibits the best dielectric heating performance under microwave irradiation among all products, probably because an optimized proportion of Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 HNSs can improve the joint heating effect where the Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 HNSs as bridges between CNTs strengthen the interfacial polarization. The nanocomposites can be totally separated from the liquid medium by magnetic decantation.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉 〈p〉Fe〈sub〉3〈/sub〉O〈sub〉4〈/sub〉 hollow nanospheres-carbon nanotubes nanocomposites in an optimized mass ratio demonstrated enhanced dielectric heating performance and achieved magnetic separation.〈/p〉 〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X18315441-ga1.jpg" width="259" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): Xiayu Ma, Zhixin Kang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We reported a facile and easily controllable electrodeposition-and-ion exchange technique for synthesis of Ni〈sub〉3〈/sub〉S〈sub〉2〈/sub〉/carbon nanotubes (CNTs) nanocomposites on the surface of Ni foam for supercapacitor applications. When tested as electrode for a supercapacitor, a large surface area of the Ni〈sub〉3〈/sub〉S〈sub〉2〈/sub〉/CNTs hybrid nanoarchitecture was proven and it showed an excellent specific capacitance of 1643 F/g at the current density of 1 A/g, and maintains 999 F/g at 20 A/g. The Ni〈sub〉3〈/sub〉S〈sub〉2〈/sub〉/CNTs electrode also displayed good cycle stability with capacitance retention of 91.5% after 2000 cycles in 3 M KOH electrolyte. Because of these outstanding properties, the Ni〈sub〉3〈/sub〉S〈sub〉2〈/sub〉/CNTs nanocomposites are becoming promising candidates for the high performance binder-free supercapacitor electrodes.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): Binxia Yuan, Xiaobo Liu, Jianfeng Liu, Min Li, Daolei Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉CuO is an attractive p-type semiconductor due to narrow band gap, low cost, and easy availability. In this paper, we obtained CuO crystals through a simple sol-gel method at room temperature. The samples were proved to be pure CuO crystals through the X-ray diffraction and Raman measurement. The reaction time and OH〈sup〉−〈/sup〉 concentration played a critical role in the structure and morphologies of pure CuO crystals. Through adjusting of the pH value, several different morphologies, including leaf-like, featheriness structure, and flake-like, were obtained. This paper provided a very simple, low cost and environmentally friendly method to control the morphologies of CuO.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): Xing Qiao, Xiuhua Wei, Yuanqiang Hao, Yintang Zhang, Maotian Xu, Baoxian Ye〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Herein, we present the synthesis and electrochemiluminescence (ECL) sensing applications of the Au-Co/GO nanocomposite. Au-Co/GO nanocomposite was prepared for the first time by decorating graphene oxide (GO) with alloy-structured Au-Co bimetallic nanoparticles (BNPs) via one-step on site chemical reduction. The obtained nanocomposite was comprehensively characterized and the results showed that alloy-structured Au-Co nanoparticles (NPs) have an average size of 4 nm and are highly dispersed on GO layers. ECL measurement revealed that the as-synthesized Au-Co/GO nanocomposite displays a synergistic effect of the GO and the Au-Co BNPs on luminol-H〈sub〉2〈/sub〉O〈sub〉2〈/sub〉 ECL signal. Further immobilization of glucose oxidase (GOD) onto the Au-Co/GO modified electrode afforded a effective ECL glucose sensor which displayed a dynamic range of 1–100 µM with a satisfactory detection limit of 0.18 μM. Furthermore, the developed enzymatic sensors were successfully applied for monitoring glucose in real human samples.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): Wenyue Dong, Zhihua Ma, Peng Chen, Qian Duan〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Conjugated polymer PCz-TPE based on carbazole and tetraphenylethylene units was synthesized 〈em〉via〈/em〉 Yamamoto-type coupling under microwave heating. PCz-TPE exhibits AIE phenomenon and high photoluminescence (PL) quantum yield in solid state due to the introduction of tetraphenylethylene moieties in polymer backbone and sidechain. Considering its electronic property and packed structure in aggregated state, PL sensing experiment toward TNT analyte was carried out based on PCz-TPE aggregates dispersion in THF/90 vol% water. As expected, PCz-TPE aggregates indicate high sensitivity for TNT detection, with maximum Stern-Volmer quenching constant of 8.5 × 10〈sup〉4〈/sup〉 M〈sup〉−1〈/sup〉. Also, paper strips test demonstrates a promising potential of PCz-TPE for solid sensor application towards nitroaromatic explosives.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X18317427-ga1.jpg" width="479" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): Fumio Narita, Hiroaki Nagaoka, Zhenjin Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Wearable Internet of Things (IoT) devices for sports require an innovative design of a self-powered technology that is able to wirelessly transmit and receive the signal (force, ambient condition) forms a body wearing item, relying upon the vibration/impact energy harvesting materials that possess lightweight but excellent resistance to intense exercise. In this study, piezoelectric hybrid carbon fiber reinforced polymer (CFRP) composite laminates are developed by embedding potassium sodium niobate (KNN) nano-particle filled epoxy interlayer, and the composite samples are successfully polarized. The output voltage of the samples due to impact load is then measured. The results show that a voltage higher than 50 mV is generated. Our work represents an important step forward in the development of piezoelectric CFRP composite materials for energy harvesting applications and opens the door for further development of lightweight, robust and efficient energy harvesting sport equipment.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): Tianhao Wang, Shivakant Shukla, Mageshwari Komarasamy, Kaimiao Liu, Rajiv S. Mishra〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A heterogeneous bimodal-grained Al〈sub〉x〈/sub〉CoCrFeNi high entropy alloy was realized through friction stir processing (FSP) with the addition of Al powders. With the bimodal-grained structure and second phases, strength was increased and ductility was retained as compared with the friction stir processed base alloy. Face-centered cubic grains in the matrix were refined from ∼500 µm to ∼15 µm by FSP and subsequent recrystallization. With addition of Al powders, localized Al-rich regions facilitated the formation of body-centered cubic phase (Al, Ni-rich) and Al rich precipitates, which further refined grain size to ∼5 µm and enhanced local strength.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): Shuai Guo, Lei Yang, Bing Dai, Fangjuan Geng, Zhenhuai Yang, Peng Wang, Gang Gao, Liangge Xu, Jiecai Han, Victor Ralchenko, Jiaqi Zhu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A novel and environmentally benign two-step method has been developed to grow 2D magnesium hydroxide (Mg(OH)〈sub〉2〈/sub〉) nanoflakes. Our method relies on the deposition of Mg films by magnetron sputtering, followed by reaction with water vapor, and does not require any catalyst or harsh acid-base conditions. The 2D nanoflake surface morphology with a crystalline hexagonal structure was dominant on the Mg(OH)〈sub〉2〈/sub〉 films. The water contact angle on the film was ∼139°, which testified the good hydrophobicity of Mg(OH)〈sub〉2〈/sub〉 films due to the nanoflake surface. The self-cleaning effect of contaminant particles on hydrophobic Mg(OH)〈sub〉2〈/sub〉 films was analyzed. Compared with other preparation methods, this two-step method is more efficient, cleaner, and simpler, which make it suitable for complex or large-area substrate surfaces. In addition, this method can be applied to other metal hydroxides or oxides.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X18317233-ga1.jpg" width="431" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): Neeru Sharma, Vikas Sharma, S.K. Sharma, K. Sachdev〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In the present study synthesis of reduced graphene oxide using 〈span〉l〈/span〉-citrulline and its application for detection of 10 ppm concentration of NO and 1% Hydrogen gas at 50 and 100 °C temperature are reported. Characterization by XRD, Raman spectroscopy and FTIR provide strong evidence for reduction of GO. The reduced graphene oxide (rGO) exhibited wrinkle structure indicating its suitability for gas sensing. Further, reduced graphene oxide shows 4.1% and 9.5% response for 10 ppm concentration of NO gas at 50 and 100 °C respectively. The response was 0.87% for 1% H〈sub〉2〈/sub〉 gas at 50 °C and 2.07% at 100 °C. This investigation indicates the usefulness of green synthesized rGO for gas sensing.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X18317245-ga1.jpg" width="260" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 236〈/p〉 〈p〉Author(s): Yiming lei, Zhengjun Yao, Haiyan Lin, Azhar Ali Haidry, Jintang Zhou, Peijiang Liu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The rise of modern communication devices has seriously imperiled human health due to electromagnetic (EM) pollution. In this context, the aim of this work is to develop novel reduced graphene oxide/Co-doped ZnNi ferrite/polyaniline ternary composites that exhibit enhanced microwave absorption properties. It is observed that the ternary composite prepared by in-situ polymerization show best EM absorption. The maximum reflection loss (〈em〉R〈/em〉〈sub〉L〈/sub〉) reaches −24.2 dB and the efficient bandwidth (〈em〉R〈/em〉〈sub〉L〈/sub〉 〈 −10 dB) is more than 3 GHz with an absorbed thickness of 1.7 mm. The in-depth analysis based on complex permittivity and permeability reveals that the improved microwave absorption ability is related to the uniform sandwich-like multilayer structure and impedance compatibility of the ternary composites. The results and analysis show that these ternary composites with small thickness and wide absorption band are the potential candidates for microwave absorption applications.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 247〈/p〉 〈p〉Author(s): Go M. Russell, Hiroshi Masai, Jun Terao〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉An oxygen-sensitive gel material containing platinum-acetylide was successfully synthesized using covalent linkages between the isocyanate groups on the platinum-acetylide crosslinker and the hydroxyl groups on commodity polymers. It was shown that the elasticity of the gel could be tailored by changing the amount of the crosslinker. Under nitrogen, the gel provided a phosphorescence at 539 nm, which was noteworthy in that the gel material displayed phosphorescent emission without fluorescence. In contrast, changing the surrounding environment of the gel to air decreased the phosphorescent intensity ratio by 94.0%. Our study demonstrated that the platinum-acetylide crosslinker provided a high oxygen sensitivity to the gel materials composed of commodity polymers.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19305233-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 247〈/p〉 〈p〉Author(s): Andrey Mochugovskiy, Natalia Tabachkova, Anastasia Mikhaylovskaya〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This study analyzes the precipitation phenomenon in the Al-3%Mg-1%Mn alloy and shows that low-temperature annealing at 360 °C enables the decomposition of an as-cast Mn-enriched supersaturated solid solution and precipitation of the quasicrystalline icosahedral phase. Icosahedrons are predominantly formed heterogeneously on the dislocations and dislocation walls. Precipitates with quasicrystalline structure contain Al and Mn, free of Si, and their size varies in a range of 17–71 nm. The Ashby-Brown contrast and the ordered positions of the precipitate and matrix reflections in the SAED and in high-resolution TEM images suggest partial coherency of the quasicrystalline precipitates and aluminum matrix.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19305269-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 27 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters〈/p〉 〈p〉Author(s): TianHua Chen, ZhiLin Liu, ZhangSheng Liu, XueYu Tao, HeLiang Fan, LiTong Guo〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A novel 2D/3D NiS/Ni〈sub〉3〈/sub〉S〈sub〉4〈/sub〉 composite was fabricated by a one-pot hydrothermal process, in which 3D hierarchical microspheres were anchored in or covered by the interconnected 2D nanosheets. The composites exhibited a high specific capacitance of 1796 F g〈sup〉-1〈/sup〉 and good capacitance retention of 80.5% at a current density of 1A g〈sup〉-1〈/sup〉 after 1000 charge-discharge cycles. Our results indicate that the interconnected 2D/3D NiS/Ni〈sub〉3〈/sub〉S〈sub〉4〈/sub〉 composites can be a promising electrode material for supercapacitor.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 247〈/p〉 〈p〉Author(s): Yu Liu, Min Sun, Guowu Tang, Guoquan Qian, Wangwang Liu, Zhenguo Shi, Wenming Zhu, Qi Qian, Shanhui Xu, Zhongmin Yang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Multimaterial fibers which integrate novel materials and/or structures into fiber configuration aim at developing multiple functionalities and high performance. Here, we demonstrate a kind of multimaterial fibers with crystalline GeSe core and K9 glass cladding by the molten core drawing method. The as-drawn fibers undergo a change in electrical conductivity when externally illuminated by an 808 nm HeNe laser. Furthermore, the Seebeck coefficient of the fibers is comparable with bulk GeSe, while the resistance is 3–4 magnitude lower than that. The results show that the GeSe core fibers have promising applications in optical switch and thermoelectric conversion field.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 247〈/p〉 〈p〉Author(s): Kwangwon Seo, Ki-Ho Nam, Sangrae Lee, Haksoo Han〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Due to rise in demand for mobile devices, development of complex stacked packaging technology such as multi-chip package, capable of both small size and high volume, are in high interest. As residual stress of individual chips increases, the degree of bending rises leading to more difficulty in package assembly process and decreased reliability of the final package product. To overcome this, deeper understanding of the thermal history and thermal behavior between the polymer film and substrates are needed. In this work, residual stress-temperature profiles of thermally stable polyimide/organically-modified layered silicate (PI/OLS) nanocomposite systems on Si wafer were investigated 〈em〉in situ〈/em〉 during imidization and cooling process. This study provides systematic approach from the perspective of substrate design for multi-stacked semiconductor package.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Materials Letters, Volume 247〈/p〉 〈p〉Author(s): Xie Li, Hui Wang, Tingting Wang, Lin Wang, Xufeng Liu, Xiaodong Zhu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this paper, NaYF〈sub〉4〈/sub〉:Yb, Er nanoparticles (NPs) were coated with hydrophilic- polystyrene (HPS) by in situ polymerization. The morphologies, structures, as well as hydrophilic stabilities of the NaYF〈sub〉4〈/sub〉: Yb, Er NPs and the NaYF〈sub〉4〈/sub〉: Yb, Er /HPS NPs composite were characterized by Transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FT-IR), Thermogravimetric analysis (TGA) and up-conversion photoluminescence spectrometry. TEM results shows that the HPS-encapsulated NaYF〈sub〉4〈/sub〉:Yb, Er NPs are well dispersed and spherical in shape in water phase, the size of spherical particles was estimated to be 140 nm, FT-IR and TGA results revealed that these NPs were coated with HPS. Meanwhile, Fluorescence tests showed that after HPS coated, the fluorescent position and intensity of NPs did not changed significantly. Settlement test results revealed that HPS coated NaYF〈sub〉4〈/sub〉:Yb, Er NPs had more dispersion and stability than uncoated ones in aqueous system.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0167577X19305063-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉