Different surface modification methods and coating materials of zinc metal anode

Rechargeable aqueous Zn-ion batteries(AZIBs)are one of the most promising energy storage devices for large-scale energy storage owing to their high specific capacity,eco-friendliness,low cost and high safety.Nevertheless,zinc metal anodes suffer from severe dendrite growth and side reactions,resulting in the inferior electrochemical performance of AZIBs.To address these problems,surface modification of zinc metal anodes is a facile and effective method to regulate the interaction between the zinc anode and an electrolyte.In this review,the current challenges and strategies for zinc metal anodes are presented.Furthermore,recent advances in surface modification strategies to improve their electrochemical performance are concluded and discussed.Finally,challenges and prospects for future development of zinc metal anodes are proposed.We hope this review will be useful for designing and fabricating highperformance AZIBs and boosting their practical applications.

In-situ polymerized PEO-based solid electrolytes contribute better Li metal batteries:Challenges,strategies,and perspectives

Polyethylene oxide(PEO)-based solid polymer electrolytes(SPEs)with good electrochemical stability and excellent Li salt solubility are considered as one of the most promising SPEs for solid-state lithium metal batteries(SSLMBs).However,PEO-based SPEs suffer from low ionic conductivity at room temperature and high interfacial resistance with the electrodes due to poor interfacial contact,seriously hindering their practical applications.As an emerging technology,in-situ polymerization process has been widely used in PEO-based SPEs because it can effectively increase Li-ion transport at the interface and improve the interfacial contact between the electrolyte and electrodes.Herein,we review recent advances in design and fabrication of in-situ polymerized PEO-based SPEs to realize enhanced performance in LMBs.The merits and current challenges of various SPEs,as well as their stabilizing strategies are presented.Furthermore,various in-situ polymerization methods(such as free radical polymerization,cationic polymerization,anionic polymerization)for the preparation of PEO-based SPEs are summarized.In addition,the application of in-situ polymerization technology in PEO-based SPEs for adjustment of the functional units and addition of different functional filler materials was systematically discussed to explore the design concepts,methods and working mechanisms.Finally,the challenges and future prospects of in-situ polymerized PEO-based SPEs for SSLMBs are also proposed.

Structural and magnetic properties of micropolycrystalline cobalt thin films fabricated by direct current magnetron sputtering

Pure cobalt(Co)thin films were fabricated by direct current magnetron sputtering,and the effects of sputtering power and pres-sure on the microstructure and electromagnetic properties of the films were investigated.As the sputtering power increases from 15 to 60 W,the Co thin films transition from an amorphous to a polycrystalline state,accompanied by an increase in the intercrystal pore width.Simultaneously,the resistivity decreases from 276 to 99μΩ·cm,coercivity increases from 162 to 293 Oe,and in-plane magnetic aniso-tropy disappears.As the sputtering pressure decreases from 1.6 to 0.2 Pa,grain size significantly increases,resistivity significantly de-creases,and the coercivity significantly increases(from 67 to 280 Oe),which can be attributed to the increase in defect width.Corres-pondingly,a quantitative model for the coercivity of Co thin films was formulated.The polycrystalline films sputtered under pressures of 0.2 and 0.4 Pa exhibit significant in-plane magnetic anisotropy,which is primarily attributable to increased microstress.

Recent advances and perspective in metal coordination materialsbased electrode materials for potassium-ion batteries

Recently,to ameliorate the forthcoming energy crisis,sustainable energy conversion and storage devices have been extensively investigated.Potassium-ion batteries(KIBs)have aroused widespread attention in these very active research applications due to their earth abundance and similar low redox potential compared to Li-ion batteries(LIBs).It is critical to develop electrode materials with large ion diffusion channels and robust structures for long cycling performance in KIBs.Metal coordination materials,including metal-organic frameworks,Prussian blue,and Prussian blue analogue,as well as their composites and derivatives,are known as promising materials for high-performance KIBs due to their open frameworks,large interstitial voids,functionality and tailorability.In this review,we give an overview of the recent advances on the application of metal coordination materials in KIBs.In addition,the methods to enhance their K-ion storage properties are summarized and discussed,such as morphology engineering,doping,as well as compositing with other materials.Ultimately,some prospects for future research of metal coordination materials for KIBs are also proposed.

Influence of quench transfer time on microstructure and mechanical properties of 7055 aluminum alloy

The influence of quench transfer time on the microstructure and mechanical properties of 7055 aluminum alloy with and without zirconium was investigated by tensile properties test,optical microscopy,scanning electron microscopy and transmission electron microscopy.For the Zr-free alloy,the strength increases to the highest value at 20 s with transfer time,and then decreases slightly.The elongation decreases slowly with transfer time within 20 s,and more rapidly after 20 s.For the Zr-containing alloy,prolonging transfer time within 20 s results in slight decrease in the strength and elongation,and rapid drop of which is observed after 20 s.For the Zr-free alloy,prolonging transfer time can increase the percentage of intergranular fracture,which is mainly caused by wide grain boundary precipitate free zone.The failure mode of the Zr-containing alloy is modified from the predominant transgranular void growth and intergranular fracture to transgranular shear and intergranular fracture with increase in the transfer time,which is attributed to the wider grain boundary precipitate free zone and coarse equilibrium η phases in the matrix.

Formation mechanism of gradient-distributed particles and their effects on grain structure in 01420 Al-Li alloy

Fine-grained 01420 Al-Li alloy sheets were produced by thermo-mechanical processing based on the mechanism of particle stimulated nucleation of recrystallization.The thermo-mechanically processed sheets were observed to contain layers of different microstructures along the thickness.The precipitate behavior of the second phase particles and their effects on the distribution of dislocations and layered recrystallized grain structure were analyzed by optical microscopy(OM),scanning electron microscopy(SEM),transmission electron microscopy(TEM) and X-ray diffractometry(XRD).The formation mechanism of the gradient particles was discussed.The results show that after aging,a gradient distribution of large particles along the thickness is observed,the particles in the surface layer(SL) are distributed homogeneously,whereas those in the center layer(CL) are mainly distributed parallel to the rolling direction,and the volume fraction of the particles in the SL is higher than that in the CL.Subsequent rolling in the presence of layer-distributed particles results in a corresponding homogeneous distribution of highly strained regions in the SL and a banded distribution of them in CL,which is the main reason for the formation of layered grain structure along the thickness in the sheets.

Continuous dynamic recrystallization and discontinuous dynamic recrystallization in (99.99%) polycrystalline aluminum during hot compression

The dynamic restoration behavior of 99.99% polycrystalline aluminum was investigated. The deformation was carried out by compression test at 533773 K and initial strain rate of 0.0022 s-1 to a true strain of （1.0） followed by water quench. Polarized optical microscopy and transmission electron microscopy were applied to observe the deformation microstructure. It’s found that discontinuous dynamic recrystallization, which is commonly observed in lower stacking fault energy metals or ultra-high purity aluminum（≥99.999%）, occurs when Zenner-Hollomon parameter（Z parameter） is low, but the true stress—strain curve doesn’t accompany stress oscillation. Continuous dynamic recrystallization occurs when Z parameter is intermediate, and only dynamic recovery takes place if Z parameter is high.

拥有超高强度的时效态Cu-20Ni-20Mn合金的力学性能和腐蚀行为

通过真空熔炼制备了拥有超高强度的Cu-20Ni-20Mn合金,并研究了其力学性能和腐蚀行为。结果表明:经过一系列变形和热处理工艺后,该合金表现出1204MPa的超高拉伸强度,且伸长率高达6.2%。随着合金在3.5%NaCl溶液中暴露腐蚀时间的延长,合金样品的腐蚀电流降低,而腐蚀表面的极化电阻和电荷转移电阻增加。腐蚀产物在暴露1 d时已在合金表面上形成,并进一步腐蚀,使得腐蚀产物层变得致密。腐蚀产物层增强了合金的耐腐蚀性能,保护合金免受进一步的腐蚀。

Octa-membered Water Ring Chain Based on Sulfonic Group in Ni(II) Complex with 2-[(E)-(2-Oxidophenyl)methyleneamino] Ethanesulfonato and 2,2′-Bipyridinyl

The title compound, [Ni（tssb）（2,2-bipy）2].5（H2O） 1 （tssbH2 =2-[（E）-（2-oxido- phenyl）methyleneamino]ethanesulfonato, 2,2-bipy = 2,2＇-bipyridinyl）, belongs to orthorhombic, space group Pbcn with a = 20.3983（18）, b = 17.6929（15）, c = 17.0897（15） nm, V= 6167.8（9） nm^3, Mr= 688.38, Z = 8, De = 1.481 g.cm^-3, F（000） = 2880,μ = 0.758 mm-1 and S =1.099. Each NiIr atom is six-coordinated by one N and one O atoms from one tssb^2- anion and four N atoms from two 2,2-bipy ligands to give a distorted octahedral geometry. Noticeably, there exists a rare octa-mem- bered water ring which presents a 1D chain by sulfonic group.

Erratum to: New high-strength Ti–Al–V–Mo alloy: from high-throughput composition design to mechanical properties

Erratum to:International Journal of Minerals, Metallurgy and Materials Volume 26, Number 9, September 2019, Page 1151https://doi.org/10.1007/s12613-019-1854-1The original version of this article unfortunately contained a mistake. The presentation of Fig. 11 was incorrect. The correct version is given below:

New high-strength Ti–Al–V–Mo alloy: from high-throughput composition design to mechanical properties

The high-throughput diffusion-multiple technique and thermodynamics databases were used to design new high-strength Ti alloys. The composition–microstructure–property relationships of the Ti64–xMo alloys were obtained. The phase fraction and composition of the α and β phases of the Ti64–xMo alloys were calculated using the Thermo-Calc software. After aging at 600℃, the Ti64–6 Mo alloy precipitated ultrafine α phases. This phenomenon was explained on the basis of the pseudo-spinodal mechanism by calculating the Gibbs energy curves of the α and β phases of the Ti64–xMo alloys at 600℃. Bulk forged Ti64–6 Mo alloy exhibited high strength and moderate plasticity after α/β-phase-field solution treatment plus aging. The tensile properties of the alloy were determined by the size and morphology of the primary and secondary α phases and by the β grain size.

Phase relationships in the Yb-Fe-Sb system at 530 ℃

Phase relationships in the Yb-Fe-Sb ternary system at 530 °C were investigated mainly by powder metallurgy and X-ray powder diffraction.Nine binary compounds（Yb6Fe23, Yb2Fe17, FeSb, FeSb2, YbSb2, YbSb, Yb11Sb10, Yb4Sb3, and αYb5Sb3） and one ternary compound（Fe4YbSb12） were confirmed in this system at 530 °C.The homogeneity range of FeSb phase extended from approximately 43at.%Sb to 45at.%Sb, the maximum solid solubility of Sb in Fe phase and Yb in FeSb phase was approximately 3at.%Sb and 1at.%Yb at 530 °C, respectively.Isothermal section of the phase diagram of the Yb-Fe-Sb ternary system at 530 °C consisted of thirteen single-phase regions, twenty-four two-phase regions, and twelve three-phase regions.

Study on stability of RECo_5 phases(RE=Dy,Gd)

The eutectoid decomposition reaction that occurred in RECo5 phases（RE=Dy and Gd ） at low temperature was discussed and confirmed by X-ray powder diffraction（XRD）, differential thermal analysis, and scanning electron microscopy.The decomposition temperature of the GdCo5 and DyCo5 were identified as 805.8 and 900 °C, respectively.The GdCo5 and DyCo5 phases could not be found in the isothermal section of Gd-Dy-Co ternary system at 800 K.Reasons for the absence of the RE2Co7 phase in the XRD patterns were discussed in detail.

氧化物在2519-T87铝合金搅拌摩擦焊接头孔洞缺陷形成中的作用

使用光学显微镜、扫描电子显微镜、电子背散射衍射仪和电子探针显微分析仪研究了氧化物在2519-T87铝合金搅拌摩擦焊接接头孔洞缺陷形成中的作用,并采用基于任意拉格朗日-欧拉方法的ABAQUS三维热力耦合有限元模型对材料流动进行分析。氧化物存在于接头隧道孔洞的边缘和微孔洞中。根据氧元素的分布和材料的流动行为,可知在搅拌摩擦焊接过程中,合金表面的氧化物往往沿着塑性材料的流动方向向下流动,聚集在肩部影响区和搅拌针端部影响区交汇处的材料流动薄弱区域,并因此阻碍材料的接触和扩散。由于材料流动不足,因此塑性变形较小,导致产生的压力不足以压合积累的氧化物,从而导致孔洞缺陷产生。

Emerging WS_(2)/WSe_(2)@graphene nanocomposites: synthesis and electrochemical energy storage applications

In recent years, tungsten disulfide(WS_(2)) and tungsten selenide(WSe_(2)) have emerged as favorable electrode materials because of their high theoretical capacity, large interlayer spacing, and high chemical activity;nevertheless, they have relatively low electronic conductivity and undergo large volume expansion during cycling, which greatly hinder them in practical applications. These drawbacks are addressed by combining a superior type of carbon material, graphene, with WS_(2) and WSe_(2) to form a WS_(2)/WSe_(2)@graphene nanocomposites.These materials have received considerable attention in electro-chemical energy storage applications such as lithium-ion batteries(LIBs), sodium-ion batteries(SIBs),and supercapacitors. Considering the rapidly growing research enthusiasm on this topic over the past several years, here the recent progress of WS_(2)/WSe_(2)@graphene nanocomposites in electrochemical energy storage applications is summarized. Furthermore, various methods for the synthesis of WS_(2)/WSe_(2)@graphene nanocomposites are reported and the relationships among these methods, nano/microstructures, and electrochemical performance are systematically summarized and discussed. In addition, the challenges and prospects for the future study and application of WS_(2)/WSe_(2)@graphene nanocomposites in electrochemical energy storage applications are proposed.

Synthesis and application of single-atom catalysts in sulfur cathode for high-performance lithium–sulfur batteries

Lithium–sulfur(Li-S)batteries are regarded as one of the most promising energy storage devices because of their low cost,high energy density,and environmental friendliness.However,Li-S batteries suffer from sluggish reaction kinetics and serious“shuttle effect”of lithium polysulfides(LiPSs),which causes rapid decay of battery capacity and prevent their practical application.To address these problems,introducing single-atom catalysts(SACs)is an effective method to improve the electrochemical performance of Li-S batteries,due to their high catalytic efficiency and definite active sites for LiPSs.In this paper,we summarized the latest developments in enhancing the electrochemical performance of cathode for Li-S batteries through introducing different SACs.Furthermore,we briefly introduced the catalytic mechanism of SACs and discussed the strategies of synthesizing SACs,including the spatial confinement strategy and the coordination design strategy.Finally,the challenges and prospects in this field are proposed.We believe that this review would help to design and fabricate high-performance Li-S batteries via introducing SACs and boost their practical application.

Preparation of a tantalum-based MoSi_(2)–Mo coating resistant to ultra-high-temperature thermal shock by a new two-step process

To develop an ultra-high-temperature resistant coating for a reusable thermal protection system,the preparation of a tantalum-based MoSi_(2)-Mo coating by a new two-step process of multi-arc ion plating and halide activated pack cementation is presented.The coating has a dense structure and is well compatible with the tantalum substrate,which can be thermally shocked from room temperature to 1750℃ for 360 cycles without failure.The mechanism of the coating’s excellent resistance to high-temperature thermal shocks is that a strong-binding gradient interface and a dense SiO_(2) oxide scale with good oxygen resistance are formed by the high-temperature self-diffusion of Si.

Effect of Different Aging Processes on the Microstructure and Mechanical Properties of a Novel Al–Cu–Li Alloy

The effects of different aging processes on the microstructure and mechanical properties of a novel Al-Cu-Li alloy have been investigated by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. It is found that the tensile properties of a novel Al-Cu-Li alloy are sensitive to aging processes, which correspond to different microstructures. σ（Al_5Cu_6Mg_2） and T_1（Al_2CuLi） phases are the major precipitates for the alloy in T6 aging condition（165 ℃/60 h）. After duplex aging condition（150 ℃/24 h ＋ 180 ℃/12 h）, σ, θ＇（Al_2Cu） and T_1 phases are detected. Only the T_1 phases can be found in the T8 state alloy（6% pre-strain＋135 ℃/60 h）. The failure modes of alloy in T6 and duplex aging conditions are dimple-intergranular fracture, while typical quasi-cleavage fracture in T8 condition.

Thermodynamic assessment of the Al–Dy, Dy–Zr and Al–Dy–Zr systems

Like Al3Sc,the Al30Dy7Zr3compound has an L12structure,implying that it could probably be used to improve the strength of aluminum alloys at elevated temperatures.Thus,it is extremely important to understand the phase relations of the Al–Dy–Zr system in the Al-rich corner.Firstly,the phase diagram of the Al–Dy binary system was re-assessed with the C15_Laves phase treated as a stoichiometric compound.Then,using the special quasirandom structure containing 16 atoms(SQS_16)to simulate Dy1-xZrx(x=0.25,0.5,and 0.75)hcp_A3 solid solutions,their enthalpies of mixing at 0 K were calculated by the first-principles method.Based on these results and the evaluated phase diagram in literature,the Dy–Zr binary system was optimized thermodynamically.Integrating the thermodynamic descriptions of the three constituent binary systems,the phase diagram of the Al–Dy–Zr ternary system in the Al-rich corner was optimized finally by coupling the first-principles calculation with the CALculation of PHAse Diagram method.A good agreementhas been reached between the calculated phase relations and the experimental results,which indicates that the current thermodynamic description is reasonable.

Effects of trace calcium and strontium on microstructure and properties of Cu-Cr alloys

Cu-0.57Cr-0.01Ca and Cu-0.58Cr-0.01Sr(wt.%)alloys were fabricated and processed by thermo-mechanical treatment.Their mechanical and electrical properties and microstructure were investigated in detail and compared with those of a Cu-0.57Cr(wt.%)alloy.The results showed that the softening resistance of the Cu-Cr alloy was significantly improved by the additions of Ca and Sr elements.Compared with the Cu-Cr alloy,the deformation microstructure of the Cu-Cr-Ca and Cu-Cr-Sr alloys was more difficult to recrystallize at elevated temperatures,and the Cr precipitates in the Cu-Cr-Ca and Cu-Cr-Sr alloys were smaller in size and had an FCC structure at any given aging state.The high strengths of the Cu-Cr-Ca and Cu-Cr-Sr alloys were mainly attributed to the dislocation strengthening provided by high-density dislocations and the precipitate strengthening provided by fine Cr precipitates.First-principles calculation showed that the segregations of Ca and Sr atoms at interface between Cr precipitates and copper matrix were favorable in energetics.This segregation effectively hindered the growth of Cr precipitates and significantly enhanced the pinning effect on the motion of dislocations and subgrain boundaries,eventually leading to the improvement in the softening resistance of the Cu-Cr alloy.