▎ 摘　　要

NOVELTY - The preparation method of monolayer phosphorus-doped graphene nano-sheet involves (1) uniformly mixing phosphate compound, carboxylate compound and a carbonate compound in a molar ratio of 0.01:(20-40):20 or 0.01:0.01:20-40:40:20, and grinding, (2) adding the mixture to a corundum porcelain boat, placing in a tubular furnace, calcining the mixture at 500-3000 degrees C for 5-600 minutes under argon atmosphere at a rate of 0.1-10 degrees C/minute, and naturally cooling to room temperature under the protection of argon atmosphere after the calcination is completed, and (3) washing the product obtained in step (2) with 0.1-2 mol/L diluted hydrochloric acid, distilled water and ethanol several times to remove excess salt, and vacuum drying the product at 80 degrees C for 10 hours. USE - Preparation method of monolayer phosphorus-doped graphene nano-sheet used in optoelectronic device and energy applications. ADVANTAGE - The method enables preparation of monolayer phosphorus-doped graphene nano-sheet with excellent catalytic activity for photohydrolysis of hydrogen and stability, by simple, economical and environmentally-friendly process.