Pore-size dominated electrochemical properties of covalent triazine frameworks as anode materials for K-ion batteries
Pore-size dominated electrochemical properties of covalent triazine frameworks as anode materials for K-ion batteries
复制标题
共价三嗪骨架作为钾离子电池负极材料的孔径主导的电化学性能
DOI：
10.1039/c9sc02340b
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发表时间：
2019-09-07
期刊：
影响因子：
8.4
通讯作者：
Zhu, Guangshan
中科院分区：
文献类型：
--
作者：
Li, Shu-Ying;Li, Wen-Hao;Zhu, Guangshan
首次开发了两种同源共价三嗪骨架（CTFs）作为高性能钾离子电池（KIBs）的负极材料。CTF的二维片状结构和规则通道使得k离子可逆地从CTF夹层中插入/脱插。特别地，发现多孔结构的尺寸效应主导了k离子的储存行为。孔径较小的CTF-0比CTF-1具有更高的k离子存储容量。分子模拟揭示了CTF-0的运行机制，表明CTF-0中的脱钾过程是放热的，而CTF-1中的脱钾过程是吸热的，这使得CTF-0中k离子的脱插比CTF-1中更可行，并有助于CTF-0具有更高的可逆容量。本研究为在分子尺度上通过结构调制来合理设计高性能有机负极材料提供了一种有希望的策略。
Two homologous covalent triazine frameworks (CTFs) have been developed for the first time as anode materials for high performance K-ion batteries (KIBs). The two-dimensional sheet-like structure as well as the regular channels in CTFs enable the process of intercalation/deintercalation of K-ions into/from the CTF interlayers reversibly. Particularly, a size effect of the porous structure is found to dominate the K-ion storage behavior. CTF-0 with a smaller pore size displays a higher K-ion storage capacity than CTF-1. Molecular simulations reveal the operation mechanism, showing that the depotassiation process in CTF-0 is exothermic while the depotassiation in CTF-1 is endothermic, which makes the deintercalation of K-ions from CTF-0 more feasible than from CTF-1 and contributes to the higher reversible capacity of CTF-0. This work provides a promising strategy for rational design of high-performance organic anode materials by structural modulation at the molecular scale.