A high-performance asymmetric supercapacitor based on Ni 3 S 2 -coated NiSe arrays as positive electrode

• Published in: New journal of chemistry 2019-01, Vol.43 (5), p.2389-2399
• Main Authors: Ye, Beirong, Gong, Chao, Huang, Miaoliang, Ge, Jinhua, Fan, Leqing, Lin, Jianming, Wu, Jihuai
• Format: Article
• Language: English
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/C8NJ05399E

NiSe rods coated with cotton-like Ni 3 S 2 were directly grown on nickel foam through a two-step process, comprising selenization and electrodeposition. The as-obtained NiSe/Ni 3 S 2 composite electrode exhibited excellent electrochemical properties, with a high specific capacitance of 8.81 F cm −2 (1259.3 F g −1 ) at a current density of 4 mA cm −2 , which was better than the value of pure NiSe electrode (5.17 F cm −2 ; 861.8 F g −1 ) at the same current density. Moreover, an asymmetric supercapacitor (ASC) was fabricated using NiSe/Ni 3 S 2 electrode and AC electrode as positive electrode and negative electrode, respectively. This ASC extended the potential window to 1.6 V and was possessed of a superior energy density of 38.7 W h kg −1 at a power density of 192 W kg −1 , with outstanding cycling stability (85.9% retention after 10 000 cycles).