文献类型：期刊文献

英文题名：Zwitterionic channels within covalent organic frameworks facilitate proton-selective transport for flow battery membrane

作者：Xu, Weiyi[1];Xu, Jipeng[1];Yi, Zhiyuan[1];Ding, Jingyi[2];Li, Siyao[1];Wang, Yixing[2];Xu, Zhi[1]

机构：[1]East China Univ Sci & Technol, Sch Chem Engn, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]Suzhou Lab, Suzhou, Peoples R China

年份：2024

卷号：299

外文期刊名：CHEMICAL ENGINEERING SCIENCE

收录：;EI(收录号：20242816685622);WOS:【SCI-EXPANDED(收录号:WOS:001268721000001)】；

基金：The authors gratefully acknowledge the research funding provided by National Key R & D Program of China (2021YFB3801301) , Shanghai Pilot Program for Basic Research (22TQ1400100-4) , National Natural Science Foundation of China (22075076) .

语种：英文

外文关键词：Flow battery; Ion conductive membrane; Covalent organic frameworks; Proton selective transport

摘要：Flow batteries demand for ion conductive membranes (ICMs) with high ion selectivity to achieve efficient energy conversion. Herein, we engineered a cysteine-modified covalent organic framework (Cys-COF) by a Thiol-ene click reaction. As a promising proton carrier, the incorporation of the Cys-COF with sulfonated poly(ether ketone) (SPEEK) yields advanced ICMs for vanadium flow batteries (VFBs). The zwitterionic cysteine groups anchored on the nanochannel walls simultaneously narrowed the pore size and ameliorated the protophilicity of Cys-COF, resulting in improved vanadium permeating resistance and proton conductivity. As a result, the optimal membrane demonstrated synchronized improvements in coulombic efficiency (95.01 %-98.84 %), voltage efficiency (95.15 %-77.84 %) and energy efficiency (90.41 %-76.94 %) with the current densities ranging from 40 to 200 mA cm(-2). Regarding stability test, it achieved exceptional energy efficiency (similar to 84.3 %) over 1100 cycles and 550 h at the constant current density of 120 mA cm(-2), outperforming pure polymer membrane and Nafion 212.