▎ 摘　　要

NOVELTY - Graphene-nanocrystalline-perovskite photocatalytic film is claimed. The graphene-nanocrystalline-perovskite photocatalytic film is obtained by spin-coating graphene-nanocrystalline- perovskite precursor solution comprising heating the nanocrystal with a concentration less than 10 mg/ml in a graphene-nanocrystal-perovskite precursor solution, where concentration of the graphene in graphene-nanocrystal-perovskite precursor solution is less than 5 mg/ml. USE - Used as graphene-nanocrystalline-perovskite photocatalytic film. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing graphene-nanocrystalline-perovskite photocatalyst film, comprising (i) dissolving tin, silver, copper, iron or cadmium salts in a mixed solvent of ethylene glycol and triethanolamine to form mixed solution, adding slowly drop wise sodium sulfide-containing diethanol solution, mixing uniformly and washing with anhydrous ethanol and dimethylformamide (DMFP) to remove impurities ions, centrifuging and filtering to obtain inorganic nanocrystals, adding inorganic nanocrystals into a polar solvent and dispersing ultrasonically to obtain an inorganic nanocrystalline solution; (ii) adding inorganic nanocrystalline solution into graphene oxide solution, mixing uniformly, adding perovskite material, mixing well, adding hydrazine hydrate, heating and reducing to obtain graphene-nanocrystalline-perovskite precursor solution; and (iii) coating graphene-nanocrystalline-perovskite precursor solution on the conductive glass with the titanium dioxide by a spin coating method, performing spin-coating process with an antisolvent treatment with chlorobenzene to spin-coating and heating conductive glass to 90-120 degrees C for 10-90 minutes. The centrifuging in step (i) is carried out at 2000-12000 revolutions/minute.