Designing Advanced Aqueous Zinc-Ion Batteries:Principles,Strategies,and Perspectives

Aqueous zinc-ion batteries(AZIBs)are an appealing battery system due to their low cost,intrinsic safety,and environmental-friendliness,while their application is plagued by the obstacles from the cathode,electrolyte,and zinc anode.Summarizing the design principles and strategies toward the optimization of cathode,electrolyte,and zinc anode is crucial for the development of AZIBs.Herein,we present a comprehensive analysis of the design principles and promising strategies toward the improvement of AZIBs.Firstly,the various reaction mechanisms are summarized and the existing issues associated with the cathode,electrolyte,and zinc anode are discussed to guide the rational design of AZIBs.Subsequently,we provide an in-depth and comprehensive discussion on the design principles and strategies for the electrodes/electrolyte/separator optimization,and analyze the advantages and disadvantages of various strategies.Importantly,the design principles and strategies of the newly appeared conversion-type AZIBs,such as Zn-S battery and Zn-Se battery,are also discussed and analyzed.The effect of design strategies on the electrochemical performance and the relationship between the current issues and strategies are also unveiled in detail.Finally,some research trends and perspectives are provided for designing better AZIBs.

Boosting Sodium Storage of Fe1?xS/MoS2 Composite via Heterointerface Engineering

Improving the cycling stability of metal sulfide-based anode materials at high rate is of great significance for advanced sodium ion batteries.However,the sluggish reaction kinetics is a big obstacle for the development of high-performance sodium storage electrodes.Herein,we have rationally engineered the heterointerface by designing the Fe1?xS/MoS2 heterostructure with abundant“ion reservoir”to endow the electrode with excellent cycling stability and rate capability,which is proved by a series of in and ex situ electrochemical investigations.Density functional theory calculations further reveal that the heterointerface greatly decreases sodium ion diffusion barrier and facilitates charge-transfer kinetics.Our present findings not only provide a deep analysis on the correlation between the structure and performance,but also draw inspiration for rational heterointerface engineering toward the next-generation high-performance energy storage devices.

Bismuth Oxide Selenium/Graphene Oxide Composites:Toward High-Performance Electrodes for Aqueous Alkaline Battery

Aqueous alkaline battery represents a promising energy storage technology with both high energy density and high power density as rechargeable batteries.However,the low theoretical capacities,kinetics and stability of anode materials have limited their developments and commercializations.In this study,we propose a novel method to produce two-dimensional layered bismuth oxide selenium(Bi_(2)O_(2)Se)and reduced graphene oxide(r GO)composites via a one-step hydrothermal method.The volume change caused by phase change during rapid charging and discharging is significantly reduced and the capacity reaches 263.83 m Ah g^(-1)at a current density of 0.5 A g^(-1).The Bi_(2)O_(2)Se/r GO electrode exhibits excellent cycling stability in which the capacity retention rate is 81.04%after 5000 cycles.More importantly,the Bi_(2)O_(2)Se/r GO nanosheet composite is used as the anode electrode material with MnCo_(2)O_(4.5)@Ni(OH)_(2)as the cathode electrode material in aqueous alkaline battery.When the energy density is 76.16 W h kg^(-1),the power density reaches 308.65 W kg^(-1).At a power density of 10.21 k W kg^(-1),the energy density remains as high as 33.86 W h kg^(-1).The results presented here may advance the understanding of the issues facing the development of aqueous battery anode materials.