Covalent Organic Framework with Multiple Redox Active Sites for High-Performance Aqueous Calcium Ion Batteries

Siqi Zhang; You-Liang Zhu; Siyuan Ren; Chunguang Li; Xiao-Bo Chen; Zhenjiang Li; Yu Han; Zhan Shi; Shouhua Feng

doi:10.1021/jacs.3c04657

Covalent Organic Framework with Multiple Redox Active Sites for High-Performance Aqueous Calcium Ion Batteries

J Am Chem Soc. 2023 Aug 9;145(31):17309-17320. doi: 10.1021/jacs.3c04657. Epub 2023 Jul 31.

Authors

Siqi Zhang¹, You-Liang Zhu², Siyuan Ren¹, Chunguang Li¹, Xiao-Bo Chen³, Zhenjiang Li⁴, Yu Han⁵, Zhan Shi¹, Shouhua Feng¹

Affiliations

¹ State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun 130012, People's Republic of China.
² State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, People's Republic of China.
³ School of Engineering, RMIT University, Carlton VIC 3053, Australia.
⁴ College of Materials Science and Engineering, Qingdao University, Qingdao 266042, People's Republic of China.
⁵ Advanced Membranes and Porous Materials Center, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.

PMID: 37525440
DOI: 10.1021/jacs.3c04657

Abstract

Organic materials are promising for cation storage in calcium ion batteries (CIBs). However, the high solubility of organic materials in an electrolyte and low electronic conductivity remain the key challenges for high-performance CIBs. Herein, a nitrogen-rich covalent organic framework with multiple carbonyls (TB-COF) is designed as an aqueous anode to address those obstacles. TB-COF demonstrates a high reversible capacity of 253 mAh g^-1 at 1.0 A g^-1 and long cycle life (0.01% capacity decay per cycle at 5 A g^-1 after 3000 cycles). The redox mechanism of Ca²⁺/H⁺ co-intercalated in COF and chelating with C═O and C═N active sites is validated. In addition, a novel C═C active site was identified for Ca²⁺ ion storage. Both computational and empirical results reveal that per TB-COF repetitive unit, up to nine Ca²⁺ ions are stored after three staggered intercalation steps, involving three distinct Ca²⁺ ion storage sites. Finally, the evolution process of radical intermediates further elucidates the C═C reaction mechanism.