Multiple Accessible Redox-Active Sites in a Robust Covalent Organic Framework for High-Performance Potassium Storage

Xue-Ling Chen; Mo Xie; Ze-Lin Zheng; Xiao Luo; Hongchang Jin; Yan-Fei Chen; Guo-Zhan Yang; De-Shan Bin; Dan Li

doi:10.1021/jacs.2c11264

Multiple Accessible Redox-Active Sites in a Robust Covalent Organic Framework for High-Performance Potassium Storage

J Am Chem Soc. 2023 Mar 8;145(9):5105-5113. doi: 10.1021/jacs.2c11264. Epub 2023 Feb 16.

Authors

Xue-Ling Chen¹, Mo Xie¹, Ze-Lin Zheng¹, Xiao Luo¹, Hongchang Jin², Yan-Fei Chen¹, Guo-Zhan Yang¹, De-Shan Bin¹, Dan Li¹

Affiliations

¹ College of Chemistry and Materials Science, Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and Applications, Jinan University, Guangzhou 510632, China.
² Hefei National Laboratory for Physical Sciences at the Microscale and Department of Applied Chemistry, University of Science and Technology of China, Hefei 230026, China.

PMID: 36795482
DOI: 10.1021/jacs.2c11264

Abstract

Covalent organic framework (COF) materials with porous character and robust structure have significant applied implications for K-ion battery (KIB) anodes, but they are limited by the low reversible capacity and inferior rate capability. Here, based on theoretical calculations, we identified that a porous bulk COF featuring numerous pyrazines and carbonyls in the π-conjugated periodic skeleton could provide multiple accessible redox-active sites for high-performance potassium storage. Its porous structure with a surface-dominated storage mechanism enabled the fast and stable storage of K-ions. Its insolubility in organic electrolytes and small volumetric change after potassiation ensured a robust electrode for stable cycling. As a KIB anode, this bulk COF demonstrated an unprecedentedly outstanding combination of reversible capacity (423 mAh g^-1 at 0.1 C), rate capability (185 mAh g^-1 at 10 C), and cyclability. The theoretical simulation and comprehensive characterizations confirmed the active sites are contributed by C═O, C═N, and the cation-π effect.