Molten-salt-templated fabrication of N, S co-doped hierarchically porous carbons for high-performance supercapacitors

• Published in: Journal of materials science. Materials in electronics 2020-07, Vol.31 (13), p.10113-10122
• Main Authors: Deng, Shuyi, He, Chengen, Qiu, Shengqiang, Zhang, Jinlong, Wang, Xianggang, Yang, Yingkui
• Format: Article
• Language: English
• Subjects: Carbon; Characterization and Evaluation of Materials; Chemistry and Materials Science; Chitosan; Current density; Electrode materials; Electrodes; Lithium chloride; Materials Science; Nitrogen; Optical and Electronic Materials; Potassium sulfate; Structural hierarchy; Supercapacitors
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-020-03557-7

Heteroatom-doped porous carbons with hierarchical structures have been regarded as promising electrode materials for high-performance supercapacitors. Herein N, S co-doped hierarchically porous carbon (NSHPC) was synthesized by a molten-salt templated method using eutectic KCl/LiCl as the template, chitosan as the carbon/nitrogen source, and K 2 SO 4 as the sulfur source, respectively. The as-prepared NSHPC exhibits a large specific surface area of 994.2 m 2 g −1 with hierarchical pores of 1.6, 2.5, and 3.7 nm in diameter, as well as high heteroatom content with 4.5% of N and 10.2% of S elements. Consequently, the NSHPC electrode delivers high specific capacitances of 277 F g −1 at a scan rate of 25 mV s −1 , and 195 F g −1 at a current density of 10 A g −1 , and also retains a 48.9% retention when the current density is increased to 50 A g −1 . Moreover, the electrode also remains 87.4% of initial capacitance after submitting 5000 charge/discharge cycles at 10 A g −1 .