▎ 摘　　要

NOVELTY - Preparation of graphene carbon nitride (g-C3N4) nanomaterial comprises grinding block g-C3N4 into powder at room temperature, adding acid solution or alkali solution, stirring, and standing; uniformly stirring, ultrasonically treating, removing supernatant, washing with deionized water, and adjusting pH to 6-8; drying, grinding into powder, adding organic solvent, ultrasonically treating, and removing supernatant; centrifuging and washing with anhydrous ethanol. The nanomaterial has a single atom thick layer. USE - Method for preparing graphene carbon nitride nanomaterial (claimed). ADVANTAGE - The method is simple and has high preparation speed and high decomposition hydrogen efficiency under irradiation of xenon lamp.