Stabilizing zinc anode using zeolite imidazole framework functionalized separator for durable aqueous zinc-ion batteries

Aqueous zinc-ion batteries(AZIBs) hold great promise as a viable alternative to lithium-ion batteries owing to their high energy density and environmental friendliness.However,AZIBs are consistently plagued by the formation of zinc dendrites and concurrent side reactions,which significantly diminish their overall service life,In this study,the glass fiber separator(GF) is modified using zeolite imidazole salt framework-8(ZIF-8),enabling the development of efficient AZIBs.ZIF-8,which is abundant in nitrogen content,efficiently regulates the desolvation of [Zn(H_(2)O)_(6)]^(2+) to inhibit hydrogen production.Moreover,it possesses abundant nanochannels that facilitate the uniform deposition of Zn~(2+) via a localized action,thereby hindering the formation of dendrites.The insulating properties of ZIF-8 help prevent Zn^(2+) and water from trapping electron reduction at the layer surface,which reduces corrosion of the zinc anode.Consequently,ZIF-8-GF achieves the even transport of Zn^(2+) and regulates the homogeneous deposition along the Zn(002) crystal surface,thus significantly enhancing the electrochemical performance of the AZIBs,In particular,the Zn|Zn symmetric cell with the ZIF-8-GF separator delivers a stable cycle life at0.5 mA cm^(-2) of 2300 h.The Zn|ZIF-8-GF|MnO_(2) cell exhibits reduced voltage polarization while maintaining a capacity retention rate(93.4%) after 1200 cycles at 1.2 A g^(-1) The unique design of the modified diaphragm provides a new approach to realizing high-performance AZIBs.

水系锌离子电池隔膜设计

Aqueous zinc-ion batteries(AZIBs)are attracting worldwide attention due to their multiple merits such as extreme safety,low cost,feasible assembly,and environmentally friendly enabled by water-based electrolytes.At present,AZIBs have experienced systematic advances in battery components including cathode,anode,and electrolyte,whereas research involving separators is insufficient.The separator is the crucial component of AZIBs through providing ion transport,forming contact with electrodes,serving as a container for electrolyte,and ensuring the efficient battery operation.Considering this great yet ignored significance,it is timely to present the latest advances in design strategies,the systematic classification and summary of separators.We summarize the separator optimization strategies mainly along two approaches including the modification of the frequently used glass fiber and the exploitation of new separators.The advantages and disadvantages of the two strategies are analyzed from the material types and the characteristics of different strategies.The effects and mechanisms of various materials on regulating the uniform migration and deposition of Zn2+,balancing the excessively concentrated nucleation points,inhibiting the growth of dendrites,and the occurrence of side reactions were discussed using confinement,electric field regulation,ion interaction force,desolvation,etc.Finally,potential directions for further improvement and development of AZIBs separators are proposed,aiming at providing helpful guidance for this booming field.