▎ 摘　　要

NOVELTY - Preparing three-dimensional graphene comprises (a) heat-treating the industrial waste carbon material at 800-2300 degrees C, and electrolytically electrolyzing the industrial carbon waste to obtain graphene carbon point solution, (b) concentrating the graphene carbon point solution by evaporating water, where the method of evaporating water is carried out by heating method, e.g. oven heating, water bath heating or oil bath heating, controlling the temperature at 60-80 degrees C for 12-100 hours, then successively replacing the liquid container with the same volume as the graphene carbon dot dispersion, and concentrating the solution to obtain 40-80 mg/ml graphene carbon dot solution, and freeze-drying at -20 to -80 degrees C for 12-48 hours to obtain graphene carbon dots, and (c) calcining the graphene carbon dots under the protection of argon gas at 300-1000 degrees C for 5-20 hours. USE - The method is useful for preparing three-dimensional graphene. ADVANTAGE - The method: uses low cost industrial waste materials, preferably polyimide, polyacrylonitrile, and asphalt or corresponding industrial waste products; and can meet the needs of industrial applications. The graphene: is not only a non-precious metal catalyst, but also can greatly improve the catalytic performance.