Fabrication of FeCo2S4/Ag NWs/G Ternary Nanocomposites with Honeycomb-Like Nanostructure for High-Performance Supercapacitors

Ferric cobalt sulfide/silver nanowires/graphene (FeCo 2 S 4 /Ag NWs/G) ternary nanocomposites with hierarchical honeycomb-like morphology have been obtained through hydrothermal synthesis. In the FeCo 2 S 4 /Ag NWs/G composite electrode, the Ag NWs provide effective electron transport channels and prevent the graphene and FeCo 2 S 4 nanosheets from aggregating. The graphene sheets can not only provide connected channels for ion transportation and charge transfer but also significantly buffer the volume change of electrode. As a result, the as-prepared FeCo 2 S 4 /Ag NWs/G composite electrode exhibits a high specific capacitance of 2689.2 F/g at a current density of 1 A/g, and excellent capacitance retention of 96.1% after 5000 charge–discharge cycles. In addition, an asymmetric supercapacitor was fabricated using FeCo 2 S 4 /Ag NWs/G as positive electrode and flower-like hierarchical porous nitrogen-doped carbon sphere as negative electrode. The assembled supercapacitor delivered a high energy density of 80.6 Wh/kg at a power density of 806 W/kg. These results demonstrate that such FeCo 2 S 4 /Ag NWs/G nanocomposites have widespread application prospects in the field of electrochemical energy storage. Graphic Abstract