文献类型：期刊文献

英文题名：High capacitance of MXene (Ti3C2Tx) through Intercalation and Surface Modification in Molten Salt

作者：Guo, Liang[1];Jiang, Wei-Yan[2,3,4];Shen, Miao[2,3,4];Xu, Cong[1];Ding, Chen-Xu[1];Zhao, Su-Fang[2,3,4];Yuan, Tao-Tao[1];Wang, Chen-Yang[2];Zhang, Xiu-Qing[1];Wang, Jian-Qiang[2,3,4]

机构：[1]East China Univ Sci & Technol, Shanghai 200237, Peoples R China;[2]Chinese Acad Sci, Shanghai Inst Appl Phys, Shanghai 201800, Peoples R China;[3]Chinese Acad Sci, Key Lab Interfacial Phys & Technol, Shanghai 201800, Peoples R China;[4]Univ Chinese Acad Sci, Beijing 100049, Peoples R China

年份：2022

卷号：401

外文期刊名：ELECTROCHIMICA ACTA

收录：;EI(收录号：20214611156102);WOS:【SCI-EXPANDED(收录号:WOS:000722146200009)】；

语种：英文

外文关键词：MXene; Intercalation; Surface terminations; Supercapacitor; Molten salt

摘要：MXenes (Ti3C2Tx) with -F surface terminations have a negative impact on electrochemical properties when used as potential electrodes in supercapacitors. In this study, Ti3C2Tx, with -F surface terminations was one-step treated in LiCl-KCl-K2CO3 molten salt at atmospheric pressure to replace -F by -O surface terminations and simultaneously introduce the intercalation of potassium. Various potassium oxygenated complexes were intercalated into the interlayer of the Ti3C2Tx resulting in the expansion of O-spacing from 0.96 to 1.05-1.21 nm, the decrease of F content from 11.23 to 3.43 at%, and the increase of O content from 0.79 to 24.18 at%. The modified Ti3C2Tx, electrode (KM-Ti3C2Tx) showed an improved specific capacity of 323.6 F g(-1) at 1 A g(-1) in 1 M H2SO4 solution and excellent capacitance retention (97% after 10,000 charging-discharging cycles at 10 A g(-1)). The storage mechanism is attributed to the reversible conversion of Ti3C2O2 / Ti3C2(OH)(2) during the insertion/extraction of hydronium (H+). Therefore, the removal of -F by -O surface terminations can form more Ti3C2O2, leading to an increase in conductivity and electrochemical active surface area. (C) 2021 Elsevier Ltd. All rights reserved.