Preparation and supercapacitive performance of manganese-cobalt sulfide/silver nanowires/graphene ternary nanocomposites

Bimetallic sulfides are potential and attractive electrode materials for high-performance supercapacitors. In this study, the manganese-cobalt sulfide/silver nanowires/graphene (MnCo2S4/Ag NWs/G) ternary nanocomposites with a hierarchical honeycomb-like nanoarchitecture have been successfully synthesized through a facile two-step hydrothermal route. Due to the unique compositional and structural advantages, the obtained MnCo2S4/Ag NWs/G composite electrode delivers a superior electrochemical capacitive performance than pure MnCo2S4 electrode and other reported MnCo2S4-based electrode materials, exhibiting a large specific capacity of 2193.6 F/g at the current density of 1 A/g, a high rate capability of 59.6% capacitance retention at 20 A/g, and a long-term cycling stability of 94.7% at 10 A/g after 3000 charge-discharge cycles. The outstanding supercapacitive performance suggests that MnCo2S4/Ag NWs/G ternary nanocomposites are promising electrode materials for high performance energy storage devices.