▎ 摘　　要

NOVELTY - Preparing a three-dimensional nitrogen-doped graphene involves using pyrazine group-containing polybenzimidazole (PzPBI) as a nitrogen source and a carbon source, forming a large p bond in the pyrazine ring and the benzimidazole ring in the polymer between the conjugated structure, arranging the rigid molecules regularly on the surface of the template nanoparticles, performing pyrolysis under the protection of argon to obtain three-dimensional nitrogen-doped graphene with high nitrogen content. USE - Method for preparing a three-dimensional nitrogen-doped graphene used as a catalyst for catalytic oxygen reduction reaction, used in a metal air battery and fuel cell, used to catalyze electrolysis of water and oxygen precipitation reaction, and used for super capacitor electrode material (claimed). ADVANTAGE - The method enables to prepare a three-dimensional nitrogen-doped graphene, which has high nitrogen content. DETAILED DESCRIPTION - Preparing a three-dimensional nitrogen-doped graphene involves using pyrazine group-containing polybenzimidazole (PzPBI) as a nitrogen source and a carbon source, forming a large p bond in the pyrazine ring and the benzimidazole ring in the polymer between the conjugated structure, arranging the rigid molecules regularly on the surface of the template nanoparticles, performing pyrolysis under the protection of argon to obtain three-dimensional nitrogen-doped graphene with high nitrogen content, where the content of pyridine nitrogen in nitrogen-doped graphene is increased due to the presence of pyrazine ring. The PzPBI is soluble, the polymer chain is composed of aromatic rigid pyridine ring and benzimidazole composition, and the molecule contains a nitrogen-rich pyrazine ring, imidazole ring, and terminal amino group, which is followed by performing pyrolysis under the protection of argon to form nitrogen-doped graphene structure, where carboxylation of the carboxyl groups in the molecule is deacidified and the pore formation is intertwined. The PzPBI solution with different particle size template is mixed with different quality ratio, stirred, steamed with a solvent, and subjected to vacuum drying and grinding, followed by subjecting to pyrolysis in a high temperature furnace under the protection argon for 2-3 hours, cooling the pyrolysis product, washing with dilute acid, and activating the three-dimensional nitrogen-doped graphene.