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.

Oxidation behavior of Mo-Si-B alloys at medium-to-high temperatures

Continuous exploration of high-temperature structural materials is being driven by the needs of gasturbine engines capable of withstanding the high-temperature environment.Relatively low melting points of currently applied superalloys restrain the further improvement of service tempe ratures.With higher melting tempe ratures above 2000℃,Mo-Si-B alloys are regarded as a new generation of ultrahightemperature structural materials.However,oxidation is a concern for the industrial application of Mo-Si-B alloys.Therefore,an in-depth understanding of the oxidation mechanisms may contribute to solving this issue,whereas relevant reviews about their recent advances are lacking.In the current work,a comprehensively systematic review about the oxidation behaviors of Mo-Si-B alloys is described for this purpose.

Generalized stability criterion for controlling solidification segregation upon twin-roll casting

Macro-and micro-segregation formed upon twin-roll casting(TRC)can be inherited from sub-rapid solid-ification to solid-state transformation,even to plastic deformation,thus deteriorating drastically mechan-ical properties of as-produced thin sheets.Although many works focusing mainly on controlling fields of thermal,concentration and convection have been reported,how to control artificially and quantitatively the segregation using a theoretical connection between processing parameters and solidification models,has not been realized,yet.Regarding it,a systematical framework integrating non-equilibrium dendritic growth and overall solidification kinetics with the TRC parameters,was constructed applying a general-ized stability(GS)conception deduced from transient thermodynamic driving force△G^(t)and transient ki-netic energy barrier Q_(eff)^(t)evolving upon solidification.Departing from this framework considering synergy of thermodynamics and kinetics(i.e.,thermo-kinetic synergy),a criterion of high△G^(t)-high GS guaranteed that the macro(i.e.,the centerline)and the micro(i.e.,the edge)segregation can be suppressed by in-creasing△G^(t)and GS at the beginning and the ending stage of sub-rapid solidification,respectively.This typical thermo-kinetic combination producing the microstructure can be inherited into the plastic de-formation,as reflected by corresponding strength-ductility combinations.This work realized quantitative controlling of TRC by a theoretical connection between processing parameters and solidification models,where,an optimization for sub-rapid solidification segregation using the GS conception including△G^(t)and Q_(eff)^(t)has been performed.

Shining light on transition metal tungstate-based nanomaterials for electrochemical applications:Structures,progress,and perspectives

Transition metal tungstate-based nanomaterials have become one of the research hotspots in electrochemistry due to their abundant natural resources,low costs,and environmental friendliness.Extensive studies have demonstrated their significant potentials for electrochemical applications,such as supercapacitors,Li-ion batteries,Na-ion batteries,electrochemical sensing,and electrocatalysis.Considering the rapidly growing research enthusiasm for this topic over the last several years,herein,a critical review of recent progress on the application of transition metal tungstates and their composites for electrochemical applications is summarized.The relationships between synthetic methods,nano/micro structures and electrochemical properties are systematically discussed.Finally,their promising prospects for future development are also proposed.It is anticipated that this review will inspire ongoing interest in rational designing and fabricating novel transition metal tungstate-based nanomaterials for high-performance electrochemical devices.

Preparation and wear properties of high-vanadium alloy composite layer

A high-vanadium alloy composite layer was prepared on the surface of a carbon steel using cast composite technology,and the wear properties of the composite layer were investigated.The results showed that the microstructure of the composite layer was composed of primary vanadium carbides(VC),flake martensite,residual austenite,and fine VC.The hardness of the cast alloy layer was 63 HRC.The abrasive wear resistance and impact wear resistance were increased by 60%and 26%,respectively,compared with those of high-chromium cast iron.The excellent wear resistance of the cast alloy layer is attributed to the high-hardness primary vanadium carbide and the large number of fine secondary vanadium carbides precipitated out of the cast alloy layer.