NOVELTY - Preparation of high efficiency platinum-cobalt silicide (Pt-CoSi2)/graphene composite electrocatalyst includes adding cobalt acetate and graphene oxide with ethylene glycol, ultrasonically mixing at room temperature, heating, adding sodium carbonate solution, stirring, filtering the reaction liquid, washing with deionized water, drying, obtaining cobalt hydroxide/graphite oxide powder, continuously charging nitrogen (N2) in tubular furnace to remove air, adding cobalt hydroxide/graphite oxide powder in tubular furnace and conducting reducing gas temperature programmed heating.    USE - Preparation of high efficiency Pt-CoSi2/graphene composite electrocatalyst used for fuel cell electrode (claimed).    ADVANTAGE - The method has controllable reaction process and particle size, low cost, and provides high efficiency Pt-CoSi2/graphene composite electrocatalyst, which has good structure stability, superior surface area, small particle size, good dispersion degree, and increased utilization rate and catalytic performance by adding CoSi2.    DETAILED DESCRIPTION - Preparation of high efficiency Pt-CoSi2/graphene composite electrocatalyst comprises respectively weighing cobalt acetate, graphene oxide and ethylene glycol, adding cobalt acetate and graphene oxide with ethylene glycol, ultrasonically mixing for 0.5-1 hour by stirring for 3-4 hours at room temperature, heating at 120-140 degrees C, adding 150-220 ml of 0.2 mol/L sodium carbonate solution, stirring for 1-3 hours, filtering the reaction liquid, washing with deionized water, drying at 100 degrees C, obtaining cobalt hydroxide/graphite oxide powder, continuously charging N2 in tubular furnace for 40 minutes to remove air, adding cobalt hydroxide/graphite oxide powder in tubular furnace, conducting reducing gas temperature programmed heating at 300-500 degrees C, reacting for 15-20 minutes, maintaining hydrogen filling speed, introducing silane (SiH4), reacting for 15-20 minutes, obtaining cobalt silicide/graphene powder, adding ethylene glycol, ultrasonically dispersing, adding chloroplatinic acid aqueous solution, conducting microwave heating reaction, naturally cooling to room temperature, filtering, sand core funnel filtering, alternately washing with anhydrous ethyl alcohol and deionized water for 10 times, drying, and obtaining the product.