Chemical design of covalent organic frameworks for aqueous zinc batteries

Abstract

Rechargeable aqueous zinc batteries (AZBs) emerge as one of the promising candidates for grid-scale energy storage battery systems. However, its practical application is hindered by unsatisfactory specific energy, cycling stability, and shelf life, which are generally caused by the degradation of cathode materials and dendrites/corrosion of Zn anodes, etc. Covalent organic frameworks (COFs) have already addressed the AZBs’ inherent issues during the past few years owing to their designable molecular structure, special inner channels, and adjustable functions. COFs can solve the problems of cathode materials due to the feasible incorporation of active components and the high stability of the covalent-based structure. The issues of the Zn anode can be well retarded by building a COF-based interfacial layer to homogenize the ion flux, provide more nucleation seeds and inhibit the corrosion reaction. Furthermore, COFs can also be utilized as organic anode instead of the Zn metal to avoid the dendrites issues. However, how to design COFs for a particular component in AZBs is still unclear due to the lack of understanding of the chemical structure-property relationship. Here, we present an analysis of the chemistry of these COFs and the specific chemistry designs on the components of AZBs will be explored. We believe this review would grab the attention of pertinent researchers and provide some inspiration for future studies.