▎ 摘　　要

NOVELTY - Composite photocatalyst is claimed. The composite photocatalyst is prepared by (i) weighing 60-80 pts. wt. L-polylactic acid, 20-30 pts. wt. graphene oxide, 2-7 pts. wt. nano silver, and 5-10 pts. wt. multi-walled carbon nanotubes, dissolving weighed L-polylactic acid in dichloromethane, adding weighed graphene oxide, nano silver, and multi-walled carbon nanotubes into solution A, dispersing ultrasonically, then dropping mixture onto a quartz substrate and casting it into a film, and placing it in a closed container for vacuum drying, (ii) weighing transition metal sulfide, silane coupling agent, and 0.5-3% guar gum aqueous solution, and mixing, (iii) weighing single-walled carbon nanotubes, a silane coupling agent, and 0.5-3% guar gum solution, and mixing, and (iv) spraying mixture C on the side of photocatalytic base film, spraying the mixture D on other side of photocatalytic base film, placing composite base film in a closed container for vacuum drying. USE - The composite photocatalyst film is useful for removing algae (claimed). ADVANTAGE - The composite photocatalyst film has high catalytic activity, no secondary pollution is generated in the water body, and also exhibits better algae removal performance during the treatment of the cyanobacteria water body. DETAILED DESCRIPTION - Composite photocatalyst is claimed. The composite photocatalyst is prepared by (i) weighing 60-80 pts. wt. L-polylactic acid, 20-30 pts. wt. graphene oxide, 2-7 pts. wt. nano silver, and 5-10 pts. wt. multi-walled carbon nanotubes, dissolving weighed L-polylactic acid in dichloromethane to obtain solution A, then adding weighed graphene oxide, nano silver, and multi-walled carbon nanotubes into solution A, dispersing ultrasonically to form mixture, then dropping the mixture onto a quartz substrate and casting it into a film, and placing it in a closed container for vacuum drying to obtain photocatalytic base film, (ii) weighing certain amount of transition metal sulfide, silane coupling agent, and 0.5-3% guar gum aqueous solution having mass percentage of 0.5-3%, and mixing them uniformly to form a mixture C, (iii) weighing certain amount of single-walled carbon nanotubes, a silane coupling agent, and 0.5-3% guar gum solution, and mixing them uniformly to form a mixture D, and (iv) spraying the mixture C on the side of the photocatalytic base film, spraying the mixture D on the other side of the photocatalytic base film, placing composite base film in a closed container for vacuum drying to obtain composite photocatalyst film.