首页期刊导航|Journal of Alloys and Compounds
期刊信息/Journal information
Journal of Alloys and Compounds
Elsevier Science S.A.
Journal of Alloys and Compounds

Elsevier Science S.A.

0925-8388

Journal of Alloys and Compounds/Journal Journal of Alloys and CompoundsSCIISTPEI
正式出版
收录年代

    (162857)Synergistic effect of Cu-doped NiO for enhancing urea electrooxidation:Comparative electrochemical and DFT studies

    Mahmoud A. HefnawySahar A. FadlallahRabab M. El-Sherif
    14页
    查看更多>>摘要：In the present work, Cu-doped NiO is fabricated and synthesized using a microwave-assisted sol-gel method using different Ni and Cu precursors ratios supported on commercial graphite rod (G) and examined as an efficient electrocatalyst toward urea electrochemical oxidation (UEO). The morphology and chemical structure of the prepared electrocatalysts is confirmed by XRD, XPS, and SEM techniques. The catalytic activity of the prepared materials is measured and examined toward UEO as a function of current density and compared with different Ni-based catalysts in NaOH solution using cyclic voltammetry, chronoamperometry, and electrochemical impedance spectroscopy (EIS). The oxidation current density of G/Ni_(0.9)Cu_(0.1) reached 32 mA cm~(-2) and its onset potential of urea oxidation peak is shifted from 0.43 V (vs. Ag/ AgCl) in NiO catalyst to 0.40 V (vs. Ag/AgCl) for G/Ni_(0.9)Cu_(0.1). The charge transfer resistance for different modified surfaces at various conditions (e.g., urea concentration, electrolyte concentration, and oxidation potential) is measured using the electrochemical impedance spectroscopy (EIS). The CO tolerance is studied using the DFT method to prove the stability of the electrodes and the performance efficiency due to Cu atoms dopping into NiO crystal. The adsorption of CO is studied upon Cu-doped NiO and compared with pristine NiO alloy at different adsorption sites- top and hallow.
      原文链接:
    • NSTL
    • Elsevier

    (162799)Microstructure and residual stress evolution in nanocrystalline Cu-Zr thin films

    J. ChakrabortyT. OellersR. Raghavan
    14页
    查看更多>>摘要：Grazing incidence X-ray diffraction (GIXRD) and scanning transmission electron microscopy (STEM) combined with energy dispersive X-ray spectroscopy (EDS) were employed to study the microstructure evolution and stress development in the nanocrystalline Cu_(100-x)-Zr_x (2.5 at% ≤ x ≤ 5.5 at%) alloy thin films. Small Zr additions to Cu led to significant lattice parameter anisotropy in the as-deposited Cu-Zr thin films both due to macroscopic lattice strain and stacking faults in the Cu matrix. Strain free lattice parameters obtained after the XRD stress analysis of Cu-Zr thin films confirmed formation of a supersaturated substitutional Cu-Zr solid solution. For the first time, the study of film microstructure by XRD line profile analysis (XLPA) confirmed progressive generation of dislocations and planar faults with increasing Zr composition in Cu-Zr alloy films. These microstructural changes led to the generation of tensile stresses in the thin films along with considerable stress gradients across the films thicknesses which are quantified by the traditional d_ψ~(hkl) - Sin~2 ψ and GIXRD stress measurement methods. The origin of tensile stresses and stress gradients in the Cu-Zr film are discussed on the basis of film growth and heterogeneous micro-structure with changing Zr composition.
      原文链接:
    • NSTL
    • Elsevier

    (163102)Achieving high strength and superior ductility in Al-Si alloy by cold rolling and friction stir processing

    Mehdi SoleymanpourHamed Jamshidi AvalRoohollah Jamaati
    15页
    查看更多>>摘要：In the current work, the influence of heat treatment, rolling, and friction stir processing (FSP) on the microstructure, hardness, tensile behavior, and fracture mechanism of hypoeutectic Al-Si alloy were investigated. The FSP led to a reduction in the aspect ratio and increased the size and sphericity of particles. Also, fine silicon and Fe-rich particles were uniformly distributed in the matrix. With increasing the rotational speed, the size and aspect ratio of particles was decreased, and their sphericity was increased. The best morphology of Si particles (size of 2.23 urn, aspect ratio of 1.91, and sphericity of 0.682) had been obtained at the rotational speed of 800 rpm. The microhardness profiles of the FSPed samples were roughly homogeneous. After the cold rolling, the yield strength (YS), ultimate tensile strength (UTS), and energy absorption (EA) were enhanced to 288.7 MPa, 296.0 MPa, and 18.5 J/cm~3, however, the total elongation (TE) was reduced to 6%. Interestingly, the YS, UTS, TE, and EA of all FSPed samples were much higher than that of the initial material. The 800-120 sample had the best tensile properties with YS, UTS, TE, and EA of 116.7 MPa, 235 MPa, 27.2%, and 57.9 J/cm~3, representing 162%, 43%, 263%, and 395% improvement, respectively. The results of the fractography exhibited that the preferential cracks propagated perpendicularly to the loading direction along the Al/Si and Al/Fe-rich interfaces in the initial and heat-treated samples. In contrast, the crack planes of the rolled and FSPed samples were oriented around 45° with respect to the loading direction. The fracture of the initial, heat-treated, and rolled samples was dominated by cleavage mode. In contrast, the FSPed samples revealed a full ductile fracture.
      原文链接:
    • NSTL
    • Elsevier

    (163111)Understanding the effect of Ni content on microstructure and mechanical properties of A384 HPDC alloy

    Nadendla Hari BabuHiiseyin DemirtasErdem Karakulak
    8页
    查看更多>>摘要：Investigations have been carried out to understand the correlation between Ni content and properties of HPDC cast A384 aluminium alloy in as-cast and heat-treated conditions. Depending on Ni content in the alloy, different Ni-bearing intermetallics were formed. Suitable heat treatment conditions were selected after a series of experiments to obtain optimal mechanical properties. Most of the Ni containing intermetallics found to be stable at solutionizing temperatures which have a dramatic effect on the mechanical properties of alloys after natural and artificial aging. The results showed that, after heat treatment, to achieve higher strength values lower Ni additions are favourable.
      原文链接:
    • NSTL
    • Elsevier

    (162902)Elastic and plastic anisotropy in a refractory high entropy alloy utilizing combinatorial instrumented indentation and electron backscatter diffraction

    Abheepsit RaturiKrishanu BiswasN.P. Gurao
    13页
    查看更多>>摘要：A comprehensive study was carried out to predict the elastic and plastic anisotropy of the non-equiatomic Mo_(15)Nb_(35)Ta_(35)V_5W_(10) Refractory High Entropy alloy (RHEA) using a high throughput combinatorial approach employing instrumented micro-indentation with electron backscatter diffraction (EBSD). The Levenberg-Marquardt optimization algorithm was utilized to determine elastic stiffness constant (C_(11) =267, Q2 = 115 and C44 = 52 ) for accessing elastic anisotropy. The anisotropy in plastic deformation of <001>, <011> and <111> orientated grains can be attributed to the activation of the different {112} < 111> slip system along with cross slip and the conservative movement of jogs on the screw dislocation. The spatial distribution of misorientation on <001>, <011> and <111> orientated grains as well as slip plane trace analysis, indicates that symmetry in misorientation pattern results from the flow of material along < 111 > slip direction on the indented surface. The results of the present investigation clearly indicate that the anisotropy in the elastoplastic behavior of novel RHEA is distinct from its constituent elements and that simple rule of mixtures is not sufficient to determine elastic modulus and lattice friction stress of RHEAs. Thus, high throughput experimental techniques are necessary to establish the structure-property linkages in novel multicomponent multi-principal RHEA compositions.
      原文链接:
    • NSTL
    • Elsevier

    (163071)Facile hydrothermal synthesis of V_2O_5 nanofibers as cathode material for aqueous zinc-ion batteries

    Xiaodong LiuChunyang LiuZhiqiang Wang
    9页
    查看更多>>摘要：Aqueous zinc-ion batteries (AZIBs) are now vigorously explored as a class of novel and competitive candidates for large-scale energy storage in terms of high safety, eco-friendliness and low cost. In order to realize efficient Zn-storage with desirable cycling stability and rate capability, constructing suitable cathode materials that possess reliable host structure and fast Zn~(2+) diffusion kinetics makes a lot of sense. Herein, novel V_2O_5 nanofibers were facilely synthesized via a hydrothermal method and employed as a cathode material for AZIBs. By matching with aqueous Zn(CF_3SO_3)_2 electrolyte, the cathode is able to achieve a specific capacity as high as 264.5 mAh g~(-1) at 200 mA g~(-1). Even conducted at a large current density of 2000 mA g~(-1) a considerable rate capability of 132.6 mAh g~(-1) can also be delivered. In addition, electrochemical reaction kinetics and ion diffusion mechanism were initially conducted to uncover the insights for efficient Zn-storage. This work is anticipated to offer feasible strategy for the design and fabrication of promising vanadium-based cathode materials for rechargeable AZIBs.
      原文链接:
    • NSTL
    • Elsevier

    (163069)Dual-layer carbon protected coaxial cable-like Si-based composites as high-performance anodes for lithium-ion batteries

    Shuling LiuQiuting WangRui Wang
    10页
    查看更多>>摘要：The Si-based composites (NC@Si@CNTs) are synthesized successfully by a facile route. Using tetra-ethylorthosilicate as Si-source, carbon nanotubes (CNTs) and polydopamine as C-source, a dual-layer carbon protected coaxial cable-like structure is achieved. As an anode for Li-ion battery, the dual-layer carbon protection to Si layer gives a initial specific discharge and reversible specific discharge capacity of 2804 and 1752 mAh g~(-1) at 200 mA g~(-1) after 150 cycles. Even at 2 A g~(-1) the NC@Si@CNTs electrode can still display an initial and reversible specific capacities of 2297 mAh g~(-1) and 910 mAh g~(-1). The dual-layer carbon protected coaxial cable-like structure also improves the rate performance and cycling stability greatly compared to Si. This might be ascribed mainly to high conductivity and buffer effect of two carbon layers during cycling, which provide more effective transmission paths for electrons and promote fast diffusion for Li ions. In addition, the N-doping of carbon layer for extra Li ions and more stable structure of the as-prepared coaxial cable also contribute to the enhanced specific capacity and cycle stability during the charging/discharging process.
      原文链接:
    • NSTL
    • Elsevier

    (162921)NH_4Sb_2(C_2O_4)F_5: A novel UV nonlinear optical material synthesized in deep eutectic solvents

    Die ZhangQiang WangTing Zheng
    6页
    查看更多>>摘要：The deep eutectic solvents was first employed to solve the hydrolysis of Sb~(3+) cations in Sb(III)-oxyacid system to explore new nonlinear optical materials, producing a novel antimony(III) fluoride oxalate named NH_4Sb_2(C_2O_4)F_5. The title compound featured a 3D noncentrosymmetric structure composed of [Sb_2(C_2O_4) F_5]~- anionic clusters and NH~4~+ cations. The cooperative effect of the planar n-conjugated [C_2O_4]~(2-) anionic groups and the Sb~(3+) cations with stereochemicaly active lone pairs induce a relatively strong SHG response (l.l×KH_2PO_4) and a large birefringence (0.111@546nm), which was confirmed by detailed theoretical calculations. The overall performances indicate that NH_4Sb_2(C_2O_4)F_5 is a potential ultraviolet nonlinear optical material. The successful application of deep eutectic solvents in the synthesis for easy hydrolytic materials system opens the door to exploring new inorganic solid functional materials.
      原文链接:
    • NSTL
    • Elsevier

    (162894)VO_2 nanobelts decorated with a secondary hydrothermal chemical lithiation method for long-life and high-rate Li-ion batteries

    Jianying MengZhengguang ZouXin Liu
    8页
    查看更多>>摘要：In this work, pre-lithiated VO_2(B) nanobelts are synthesized by a two-step hydrothermal method. After pre-lithiation, the VO_2(B) nanobelts exhibit a uniformly dispersed morphology with a large specific surface area. Compared to pure VO_2(B) nanobelts, the pre-lithiated VO_2(B) nanobelts show much better electrochemical performance in terms of cycling stability and high-rate capability. The lithium-ion diffusivity in the pre-lithiated VO_2(B) nanobelts is enhanced due to enlargement of the crystal lattice after pre-lithiation. The pre-lithiated VO_2(B) nanobelt cathode delivers an initial specific capacity of 264 mA h g~(-1 at 0.1 A g~(-1 with a capacity retention of 81.6% after 100 cycles, which is superior to that obtained for pure VO_2(B) under the same conditions (initial capacity of 221.5 mA h g~(-1 and capacity retention of 63.3%). Moreover, the pre-lithiated VO_2(B) nanobelt electrode exhibits outstanding long-term cycling stability (capacity retention of 87.2% after 800 cycles at 1000 mA g~(-1)). These results indicate that pre-lithiated VO_2(B) nanobelts have great potential to be applied as an advanced cathode material for next-generation lithium-ion batteries.
      原文链接:
    • NSTL
    • Elsevier

    (162864)Holistically modulating charge recombination via trisiloxane surface treatment for efficient dye-sensitized solar cells

    Shenghua HeLuwen ShangYueyue Gao
    8页
    查看更多>>摘要：Dye-sensitized solar cells (DSSCs) with TiO_2 as electron transport layer (ETL) demonstrate great potential in the field of photoelectric devices featuring low cost and high power conversion efficiency (PCE). However, the photovoltaic performance of DSSCs based on TiO_2 ETL is still confined by the undesirable charge recombination occurring in TiO_2 layer (intrinsic defects), dye layer (self-quenching) and at the interface between TiO_2 and electrolyte (back electron transfer). Herein, we firstly adopted a trisiloxane molecule (denoted as TSi) to holistically reduce the abovementioned charge recombination of DSSCs via passivating surface defects of TiO_2, fine-tuning dye molecules arrangement and forming interfacial energy barrier. As a result, the Z907-based DSSCs with TiO_2/TSi ETL deliver a high PCE of 9.43%, increasing over 16% than that of DSSCs without TSi treatment. Meanwhile, the DSSCs based on TiO_2/TSi ETL present stronger endurance to high humidity and better long-term stability versus that of the DSSCs without TSi treatment. Our work provides a simple yet effective strategy to holistically reduce charge recombination of devices for improving the photovoltaic performance and stability of DSSCs.
      原文链接:
    • NSTL
    • Elsevier