▎ 摘　　要

NOVELTY - Preparation of cobalt tetroxide/graphene composite supercapacitor material by gas phase diffusion method involves preparing 50 mL mixed solution using cobalt chloride raw material powder and graphene oxide solution, adding mixed solution to 100 mL beaker, magnetically stirring, adding aqueous ammonia to 50 mL beaker, placing the two beakers in sealed desiccators, covering desiccator with glass sealing cover, leaving still for 4-10 hours, filtering reaction precipitate in 100 mL beaker with sand core filter device under reduced pressure, washing with absolute ethanol and distilled water, drying at 60 degrees C for 2 hours to obtain blue-green powder, heat-treating in tube furnace under protection of high-purity nitrogen at 300 degrees C under heating rate of 5 degrees C/minute for 3 hours, cooling to obtain black cobalt tetroxide/graphene composite supercapacitor materials, and performing three-electrode test method using composite supercapacitor material as supercapacitor active material. USE - Preparation of cobalt tetroxide/graphene composite supercapacitor material by gas phase diffusion method. ADVANTAGE - The preparation method adopts gas phase diffusion chemical precipitation method to prepare composite supercapacitor material with uniform particle size and ultrafine nanoparticles, and excellent specific capacitance and rate performance. DETAILED DESCRIPTION - Preparation of cobalt tetroxide/graphene composite supercapacitor material by gas phase diffusion method involves preparing 50 mL mixed solution using 2.5 mmol cobalt chloride raw material powder and 1 g/L graphene oxide solution, adding 50 mL mixed solution comprising 50-10 mL cobalt salt solution and 0-40 mL graphene solution to 100 mL beaker, magnetically stirring, adding 5-20 mL of 25-28% aqueous ammonia as vapor diffusion precipitant to 50 mL beaker, placing the two beakers in sealed desiccators, covering desiccator with glass sealing cover, leaving still for 4-10 hours, filtering reaction precipitate in 100 mL beaker with sand core filter device under reduced pressure, washing three times with absolute ethanol and distilled water, drying at 60 degrees C for 2 hours to obtain blue-green powder, heat-treating precipitate in tube furnace under the protection of high-purity nitrogen at 300 degrees C under heating rate of 5 degrees C/minute for 3 hours, naturally cooling to obtain black cobalt tetroxide/graphene composite supercapacitor materials, and performing three-electrode test method using composite supercapacitor material as supercapacitor active material. The composite supercapacitor material has measured specific capacitance of 389.4 F/g at current density of 1 A/g and 323.6 F/g at current density of 10 A/g and rate performance of 83.1%.