Multifunctional Covalent Organic Frameworks for Zinc Metal Anodes

Aqueous zinc-ion batteries (AZIBs) are one promising electrochemical energy storage system attributed to their high theoretical capacity, relatively low cost as well as high safety. Nevertheless, the formation for zinc dendrites at the anode side severely impedes their electrochemical performance. Covalent organic frameworks (COFs), as promising porous materials, possess some broad application prospects in advanced energy storage and conversion systems and they have demonstrated their versatility in settling the issues for zinc metal anodes. In this current review, the multifunctionality of COFs is reviewed. The overview toward zinc metal anodes is firstly overviewed. Then, multifunctional covalent organic frameworks toward stable zinc metal anodes is summarized. By construction of nanoporous structure, introduction of negative charges and utilization of zincophilic properties, COFs could act as protective layers for ZIBs. In addition, COFs have been utilized as the anode materials, separators and electrolytes in AZIBs. Finally, some perspective of COFs toward highly stable AZIBs are presented. This review could plat a platform for the application of the porous materials in advanced high-energy-density batteries.