▎ 摘　　要

Assembly of Ni2S-coated rGO flower-like hierarchical microstructure on Ni foam (Ni2S@rGO/Ni foam) was fabricated by simply heating Ni foam in the alkaline solution containing GO, thiosulfate and TG at 60 degrees C. Two novel reactions are involved in the fabrication of Ni2S@rGO/Ni foam. One is the redox reaction between Ni foam and graphene oxide (GO). During the reaction, GO was reduced to reduced graphene oxide (rGO) while elemental nickel was oxidized to Ni cation. Another is the hydrolysis of thiosulfate in alkaline solution catalyzed by 1-thioglycerol (TG). The product of the hydrolysis reaction is S2-, which may react with transition metal cations to form transition metal sulfide (TMS). Ni2S@rGO/Ni foam exhibits high capacitance (3.92 F cm-2 at 10 mA cm- 2) and long cycling life (55.5 % retention after 5000 charge/discharge cycles). The excellent energy storage performances of the supercapacitor device with Ni2S@rGO/Ni foam and activated carbon (AC) as positive and negative electrodes exhibit the great application potential of Ni2S@rGO/Ni foam.