Controlled synthesis and growth mechanism of zinc cobalt sulfide rods on Ni-foam for high-performance supercapacitors

Abstract Rod-like zinc cobalt sulfide (ZCS) with controlled uniform structure was synthesized using a single-step hydrothermal method and its growth mechanism was investigated. A ZCS-based electrode showed an ultrahigh capacitance of 2,418 F g −1 (967 C g −1 ) at 1 A g −1 with a good cycling stability of 83% after 10,000 cycles. Moreover, an asymmetric ZCS-12//activated carbon supercapacitor, exhibited a high capacitance of 142 F g −1 (227 C g −1 ) at 0.5 A g −1 and a high energy density of 51 Wh kg −1 and a high power density of 8 kW kg −1 , highlighting the next generation high performance supercapacitors.