Covalent organic frameworks for high-performance rechargeable lithium metal batteries: Strategy, mechanism, and application

Lithium metal is recognized as promising anode materials for achieving high energy density lithium metal batteries (LMBs) due to it has high theoretical capacity (3860 mAh g-1) and low electrochemical potential (-3.04 V). However, the practical application of LMBs is restricted by uncontrollable Li dendrites and fragile solid electrolyte interphase (SEI). Covalent organic frameworks (COFs) provide an ideal platform for addressing the inherent problems of LMBs owing to their ordered Li+ transport channels and plentiful lithiophilic groups to promote uniform Li+ deposition, restrain Li dendrites, and eliminate side reactions. This paper comprehensively summarizes and discusses the application COF in LMBs. The design principle of COF and Li dendrites formation mechanisms are elucidated. Meanwhile, the latest developments in COF as separators, artificial SEIs and solid-state electrolytes to optimize LMBs performance are reviewed. Finally, COFs facing challenges and their future investigation prospects are discussed. We expect the review to provide theoretical guidance for the design of multifunctional COF and motivate researchers to further investigate the potential of COF in energy storage systems.