Hollow rod-like hybrid Co2CrO4/Co1−xS for high-performance asymmetric supercapacitor

• Published in: Journal of materials science. Materials in electronics 2019-01, Vol.30 (2), p.1045-1055
• Main Authors: Ge, Jinhua, Wu, Jihuai, Ye, Beirong, Fan, Leqing, Jia, Jinbiao
• Format: Article
• Language: English
• Subjects: Activated carbon; Capacitance; Characterization and Evaluation of Materials; Chemistry and Materials Science; Electrodes; Electrolytes; Energy storage; Flux density; Materials Science; Microscopy; Optical and Electronic Materials; Supercapacitors
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-018-0373-6

A hollow rod-like hybrid of Co 2 CrO 4 /Co 1−x S is synthesized via a facile two-step hydrothermal process, and the mass ratio for Co 2 CrO 4 –Co 1−x S in the hybrid is optimized. The Co 2 CrO 4 /Co 1−x S electrode exhibits excellent properties with high specific capacitance of 1580 F g −1 at current density of 1 A g −1 and possesses good rate performance. An asymmetric supercapacitor of Co 2 CrO 4 /Co 1−x S//AC is assembled, which can be operated within a voltage range of 0–1.6 V, demonstrating specific capacitance of 92.3 F g −1 , energy density of 32.8 Wh kg −1 and highest power density of 4003.3 W kg −1 . Moreover, the specific capacitance of the device remains 88% after 5000 cycles. The good characteristics of Co 2 CrO 4 /Co 1−x S//AC can be ascribed to the hollow rod-like structure and the positive synergistic effects of Co 2 CrO 4 and Co 1−x S components in the hybrid. The unique structure and superior performances render Co 2 CrO 4 /Co 1−x S hybrid as a promising candidate for energy storage device.