▎ 摘　　要

NOVELTY - A nitrogen-doped graphene is produced by preparing a mixture by introducing 1-50 mass% metallic sodium (Na) and 50-99 mass% N,N-dimethylformamide (DMF) within a chamber having a Teflon (RTM: PTFE) surface, subjecting the prepared mixture placed into heat and pressure-controlled solvothermal reactor to solvothermal process at 70-210 degrees C and at reactor pressure of 10-90 bar for 12-60 hours, liquefying the mixture by adding purified water or mineral acid solutions such as hydrochloric acid (HCl), sulfuric acid (H2SO4), perchloric acid (HClO4) such that final pH value is 1-14, drying the liquid mixture having a pH value within the range of 1-14 in a vacuum oven at 80-160 degrees C, pyrolyzing the dried mixture in the presence of argon (Ar), nitrogen (N2), and/or water (H2O) at a temperature of 450-900 degrees C in the horizontal quartz-tube furnace. The particle size can be adjusted upon adjusting the pH value of mixture to 1-14 at one of production steps after solvothermal process. USE - Production of nitrogen-doped graphene used as cathode electrocatalyst for metal-air batteries. ADVANTAGE - The method obtains graphene product with high electrical conductivity, high electrocatalytic activity, uniform pore structure, and with a structure in which the particle sizes can be adjusted. The graphene product has high product efficiency in industrial scale. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for producing nitrogen-doped graphene which involves doping organic and/inorganic compounds of silicon (Si) and iron (Fe) elements to nitrogen-doped graphene and adjusting particle size upon adjusting the pH value of mixture to 1-14 at one of the production steps after the solvothermal process including preparing the mixture by introducing 1-50 mass% metallic sodium (Na) and 50-99 mass% N,N-dimethylformamide (DMF) within a chamber having Teflon (RTM: PTFE) surface, adding the organic and/or inorganic compounds of silicon (Si) and iron (Fe) elements to mixture such that proportion is 0.1-10 mass% of the total mass, subjecting the prepared mixture placed into the heat- and pressure-controlled solvothermal reactor to solvothermal process at 70-210 degrees C and at reactor pressure of 10-90 bar for 12-60 hours, liquefying the mixture by adding purified water or mineral acid solutions such as hydrochloric acid (HCl), sulfuric acid (H2SO4), perchloric acid (HClO4) such that the final pH value is 1-14, drying the liquid mixture having a pH value of 1-14 in a vacuum furnace at 80-160 degrees C, and pyrolyzing the dried mixture in presence of argon (Ar), nitrogen (N2) and/or water (H2O) at 450-900 degrees C in horizontal quartz tube furnace.