▎ 摘　　要

Nickel selenide nanoparticles uniformly supported on graphene nanosheets to form NiSe2/rGO composites were prepared via one-step mixing solvothermal method. The NiSe2/rGO composite possesses a high specific capacity of 137.7 mAh g (1A g(-1)) and displays an excellent rate property. Moreover, there are NiSe2/rGO-20 as electrode materials assembling asymmetric supercapacitors, which manifests high energy density (33.13 Wh kg(-1)) at a power density (850 W kg(-1)) and the capacity can maintain of 80 % after 10,000 cycles. Therefore, NiSe2/rGO composite can be a potential candidate for high-efficiency asymmetric supercapacitors.