Structure–Performance Relationships of Covalent Organic Framework Electrode Materials in Metal-Ion Batteries

Abstract

Covalent organic frameworks (COFs) have shown great potential as high-performance electrode materials for metal-ion batteries in view of their relatively high capacity, flexibly designable structure, ordered porous structure, and limited solubility in electrolyte. To develop more attractive COF electrode materials, it is necessary to understand their structure–performance relationships. This Perspective focuses on discussing the relationships between structure (molecular structure, micro structure, and electrode structure) and performance (voltage, capacity, cycling stability, and rate performance) of COF electrode materials in metal-ion batteries. Among the reported COF electrode materials, those with all linkages being redox active based on CO and CN groups would be the most promising cathode materials because of their high capacity (∼500 mAh g–1), moderate working voltage (∼2 V vs Li+/Li), and good cycling stability. To accelerate practical application of COF electrode materials in metal-ion batteries, future work should pay more attention to function-oriented molecular structure design via theoretical simulations, as well as full-cell fabrication and evaluation. This Perspective will stimulate high-quality research that might lead to future commercialization.

Calix[8]quinone: A new promising macrocyclic molecule as an efficient organic cathode in lithium ion batteries with a highly‐concentrated electrolyte

“…Organic electrode materials (e.g., conducting polymers, organosulfurs, concerning radicals, and carbonyl compounds) are emerging as key elements in secondary batteries due to their high specific capacity, design flexibility, abundant raw materials, environmental friendliness, and renewability 1–7 . Among all organic materials, conjugated carbonyl compounds with various merits such as high capacity and fast kinetics have become the most widely studied organic cathode materials 8–11 . However, the dissolution of organic materials in organic secondary batteries still frustrates many scientists.…”

“…[1][2][3][4][5][6][7] Among all organic materials, conjugated carbonyl compounds with various merits such as high capacity and fast kinetics have become the most widely studied organic cathode materials. [8][9][10][11] However, the dissolution of organic materials in organic secondary batteries still frustrates many scientists. Particularly, small carbonyl compounds are readily soluble, leading to poor cycling stability.…”

Conducting polymers with redox active pendant groups: their application progress as organic electrode materials for rechargeable batteries

“…With these features, rational design of targeted functionalities can be realized, such as facilitating the penetration of electrolytes and enhancing the ion transport. [40][41][42] Thus, some of the COFs with a well-defined porous structure and good conductivity have attracted increasing interest in the field of electrochemical energy storage.…”

Storing Mg Ions in Polymers: A Perspective

“…COFs are promising in RMBs as mentioned above. [ 51 ] Noted that the stability of COFs is affected by the type of self‐connecting bonds. The cyclic stability of azo‐based COF material of thiazole‐fused ring has been proved to be significantly higher than that of imine ring in LIBs.…”