▎ 摘　　要

NOVELTY - A nano-titanium dioxide-graphene composite photocatalyst comprises a main active material, an additive, and deionized water. The main active material is nano-titanium dioxide-graphene composite material. USE - The nano-titanium dioxide-graphene composite photocatalyst is useful for degrading formaldehyde. ADVANTAGE - The photocatalyst has high photocatalytic activity and excellent air purification and photocatalytic degradation of formaldehyde. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing the nano-titanium dioxide-graphene composite photocatalyst, which involves: (S1) preparing nano titanium dioxide by preparing a proper concentration of titanium sulfate solution and sodium hydroxide solution, dripping a titanium sulfate solution into the sodium hydroxide solution under the corresponding temperature conditions, vigorously stirring to obtain a white flocculant product (F1), adjusting the pH value of the product (F1) through titanium sulfate solution or sodium hydroxide solution to neutral (pH of 7), carrying out static layering, washing by suction filtration method until the sulfate ion is washed, and cleaning to obtain nano-titanium dioxide (F2); (S2) compounding nano titanium dioxide with graphene by compounding the nano titanium dioxide (F2) obtained in step (S1) with graphene, and adding deionized water to prepare an active ingredient stock solution (Y1); (S3) preparing a photocatalyst stock solution (Y2) by mixing the active ingredient stock solution (Y1) obtained in step (S2) with the additive; and (S4) preparing nano-titanium dioxide-graphene composite photocatalyst by mixing the photocatalyst stock solution (Y2) obtained in step (S3) with deionized water.