A 2D covalent organic framework as a high-performance cathode material for lithium-ion batteries

Wu, MM (Wu, Manman)^{[ 1,2,3 ]} ; Zhao, Y (Zhao, Yang)^{[ 1,2,3 ]} ; Sun, BQ (Sun, Binqiao)^{[ 1,2,3 ]} ; Sun, ZH (Sun, Zhenhe)^{[ 1,2,3 ]} ; Li, CX (Li, Chenxi)^{[ 1,2,3 ]} ; Han, Y (Han, Yu)^{[ 1,2,3 ]} ; Xu, LQ (Xu, Lingqun)^{[ 1,2,3 ]} ; Ge, Z (Ge, Zhen)^{[ 1,2,3 ]} ; Ren, YX (Ren, Yuxin)^{[ 1,2,3 ]} ; Zhang, MT (Zhang, Mingtao)^{[ 1,2,3 ]} ; Zhang, Q (Zhang, Qiang)^{[ 4 ]} ; Lu, Y (Lu, Yan)^{[ 4 ]} ; Wang, W (Wang, Wei)^{[ 5 ]} ; Ma, YF (Ma, Yanfeng)^{[ 1,2,3 ]} ; Chen, YS (Chen, Yongsheng)^{[ 1,2,3 ]}

NANO ENERGY, 2020, 70: 文献号: 104498

DOI: 10.1016/j.nanoen.2020.104498

摘要

Organic cathode materials for lithium storage have attracted wide attention owing to their very diverse structures and largely tuned engineered molecular levels. However, it remains a great challenge to design a cathode material with simultaneously combined features of high specific capacity, cycle life and rate performance. Here, based on our proposed strategy, we design and report a BQ1-COF consisting of maximum active groups (C=O and C=N) with minimal inactive groups, which when used as cathode materials for lithium-ion batteries give a reversible capacity of 502.4 mA h g(-1) at 0.05C, so far the highest capacity among polymer-based cathode materials. More importantly, the stable framework structure delivers an excellent capacity retention (81% after 1,000 cycles at 1.54 A g(-1)), and it is noted that the rate performance (170.7 mA h g(-1) even at 7.73 A g(-1)) is far superior to previous related reports. These results indicate that maximizing the loading of redox active groups in a stable network structure is an effective strategy to design organic cathode materials simultaneously with high capacity and outstanding cycle and rate performance for next generation lithium-ion batteries.