▎ 摘　　要

NOVELTY - Preparing cobalt trioxide/graphene composite material involves preparing graphene oxide by hummers method. 1-2 ml of 0.2 Molar cobalt acetate and 1-2 ml of 4.5 mg/ml of graphene oxide are mixed with 34-36 ml of absolute ethanol. The mixture is ultrasonicated for 20-30 minutes and then heated at 75-85 degrees C for 9-10 hours to obtain nano cobalt(II,III) oxide particles grown on oxidized graphene surface which is further heated at 145-155 degrees C for 2.5-3.5 hours for further crystallization of cobalt(II,III) oxide nanoparticles on graphene oxide surface followed by the reduction of graphene oxide. USE - Method for preparing cobalt trioxide/graphene composite material used in nickel hydrogen battery and lithium ion battery (claimed). ADVANTAGE - The method enables to prepare cobalt trioxide/graphene composite material which tends to increase the discharge capacity of nickel hydrogen battery and lithium ion battery. DETAILED DESCRIPTION - Preparing cobalt trioxide/graphene composite material involves preparing graphene oxide by hummers method. 1-2 ml of 0.2 Molar cobalt acetate and 1-2 ml of 4.5 mg/ml of graphene oxide are mixed with 34-36 ml of absolute ethanol. The mixture is ultrasonicated for 20-30 minutes and then heated at 75-85 degrees C for 9-10 hours to obtain nano cobalt(II,III) oxide particles grown on oxidized graphene surface which is further heated at 145-155 degrees C for 2.5-3.5 hours for further crystallization of cobalt(II,III) oxide nanoparticles on graphene oxide surface followed by the reduction of graphene oxide. The obtained product is washed with ethanol and water and dried in vacuum at 22-25 degrees C for 10-12 hours to obtain desired cobalt trioxide/graphene composite material with pore size 0.1-0.2 mu m.