▎ 摘　　要

NOVELTY - A nitrogen-doped carbon-coated cobalt-nickel sulfide-graphene composite electrode material is prepared by (1) adding graphene oxide to ethylene glycol solution and ultrasonically dispersing so that graphene oxide is uniformly dispersed in ethylene glycol solution; (2) adding polyvinyl pyrrolidone, cobalt acetate tetrahydrate, and nickel acetate tetrahydrate to solution of step (1), fully dissolving in solution, transferring mixture to round bottom flask and placing it in oil bath, naturally cooling to room temperature, washed with absolute ethanol for a number of times, and drying washed product; and (3) mixing centrifugally dried product of step (2) with thiourea in porcelain boat, calcining porcelain boat in argon-protected tube furnace for one-step carbonization and vulcanization, and naturally cooling to room temperature. USE - Preparing nitrogen-doped carbon-coated cobalt-nickel sulfide-graphene composite electrode material for supercapacitor. ADVANTAGE - The method produces cobalt-nickel sulfide particles with uniform size on surface of electrode material and electrode material with high specific capacitance and excellent rate performance and cycle stability. Nitrogen-doped carbon is uniformly loaded on graphene substrate.