▎ 摘　　要

NOVELTY - Photocatalytically active algicide comprises graphene oxide and deionized water, where the mass concentration of graphene oxide in the deionized water is 0.1% to 1.6%. The graphene oxide is graphene oxide powder with a single-layer or multiple-layer structure. USE - Photocatalytically active algicide for removing algae by photochemical catalytic activity (claimed). ADVANTAGE - The Photocatalytically active algicide has no other chemical reagents, and is an eco-friendly green algicide with good algae removal effect. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) a method for preparing photocatalytic active algicide, which involves dissolving graphene oxide in deionized water to obtain a mixed solution, ultrasonically dispersing the mixed solution to prepare a graphene oxide dispersion; and performing dialysis of the graphene oxide dispersion liquid to recovered liquid of desired product; and (2) a method for removing algae by photochemical catalytic activity, which involves preparing photocatalytic activity algicide; adding photocatalytic active algicide to the water body to obtain a mixed solution, where the concentration of the photocatalytic active algicide in the mixed solution is 0.1-10 ppm; and irradiating the mixed solution.