Nickel catalytic graphitized porous carbon as electrode material for high performance supercapacitors

• Published in: Energy (Oxford) 2016-04, Vol.101 (C), p.9-15
• Main Authors: Wang, Keliang, Cao, Yuhe, Wang, Xiaomin, Kharel, Parashu Ram, Gibbons, William, Luo, Bing, Gu, Zhengrong, Fan, Qihua, Metzger, Lloyd
• Format: Article
• Language: English
• Subjects: Capacitance; Carbon; Charge; Charge density; Current density; Discharge; Electrode materials; Nickel catalytic graphitized; Nitrogen doped carbon; Porous carbon; Supercapacitor; Supercapacitors
• ISSN: 0360-5442
• DOI: 10.1016/j.energy.2016.01.059

Whey-protein-derived nitrogen-doped porous carbon has been prepared by preliminary carbonization at 400 °C and final KOH activation at 700 °C combined with catalytic graphitization. Physical characterization indicated that the nitrogen-doped activated electrode material had a large specific surface area (2536 m2 g−1) and plenty of interconnected cavities, which greatly improved the performance of supercapacitors. Electrochemical measurements demonstrated that the as-prepared activated electrode material had exceptionally high capacitance of 248 F g−1 at charge/discharge current density of 0.1 A g−1. Moreover, the prepared supercapacitors exhibited ideal capacitive behavior with nearly no capacitance loss in 6 mol L−1 KOH at different charge/discharge current densities ranging from 0.1 to 5 A g−1 after 1000 charge/discharge cycles. The derived energy density was 12.4 Wh kg−1 at a power density of 495 W kg−1 under operational conditions. These results suggested that the whey-protein-derived porous carbon is a promising supercapacitor electrode material. [Display omitted] •Porous N-doped carbon was prepared by KOH activation under Ni catalysis.•High specific surface area, low cost, and good electrical conductivity.•High specific capacitance of 248 F g−1 at 0.1 A g−1 and excellent cyclic stability.