文献类型：期刊文献

英文题名：High-surface-area and high-nitrogen-content carbon microspheres prepared by a pre-oxidation and mild KOH activation for superior supercapacitor

作者：Ma, Cheng[1];Chen, Xueyong[1];Long, Donghui[1];Wang, Jitong[1];Qiao, Wenming[1,2];Ling, Licheng[1,2]

机构：[1]East China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Key Lab Specially Funct Polymer Mat & Related Tec, Shanghai 200237, Peoples R China

年份：2017

卷号：118

起止页码：699

外文期刊名：CARBON

收录：;EI(收录号：20171503568926);WOS:【SCI-EXPANDED(收录号:WOS:000401120800080)】；

基金：This work was partly supported by MOST (2014CB239702) and National Science Foundation of China (No. 21576090, No. 51302083, No. 51172071), and Shanghai Rising Star Program (15QA1401300).

语种：英文

外文关键词：Capacitance - Carbon - Electrolytes - Etching - Microspheres - Potassium hydroxide - Supercapacitor - Porous materials - Surface chemistry - Chemical activation

摘要：KOH activation is a well-accepted approach to develop microporosity for porous carbons, but its severe etching reactions could inevitably destroy the structural integrity and diminish the heteroatomic surface chemistry of the resultant carbons. Herein, we report a method to prepare well-defined micro-spherical, high-surface-area and high-nitrogen-doping carbons via a mild KOH activation. The key to our synthesis relies in the pre-oxidation of the nitrogen-rich polymeric microspheres from resorcinol, formaldehyde and melamine, which could enrich nitrogen heteroatoms into the resultant carbonized framework, resulting in the carbon easily activated by KOH with low surface etching and high residual of nitrogen heteroatoms. The obtained carbons possess high specific surface area of 2234-3121 m(2)/g, high nitrogen content of 6.1-12.5 wt % and well-preserved spherical morphology. When used as the electrodes of supercapacitor, these carbon microspheres could deliver high specific capacitance up to 309 F/g, excellent rate performance and high cyclic performance of 96% after 5000 cycles in H2SO4 electrolyte. Furthermore, it is found that nitrogen functionalities could contribute considerable pseudo-capacitance, basically through Faradic reactions of the nitrogen. (C) 2017 Elsevier Ltd. All rights reserved.