▎ 摘　　要

NOVELTY - Perovskite photocatalyst comprises catalyst which is the composite formed by cesium-silver-bismuth-iodide (Cs2AgBiI6) and oxidation graphene. USE - Perovskite photocatalyst used in catalyzing and degrading sudan red III which is not soluble in water (claimed). ADVANTAGE - The perovskite photocatalyst solves the environment problem caused by the toxic and harmful organic matter in the water resource has good practical application prospect, and method is simple, easy to operate, the device requirement is not high and it has low cost and low energy consumption. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) a method for preparing perovskite photocatalyst which involves preparing liquid by dissolving cesium iodide, silver iodide, bismuth iodide in dimethyl sulfoxide; stirring to make it dissolve to obtain precursor liquid; preparing under the stirring state, adding the precursor preparation into isopropanol or isopropanol solution containing graphite, stirring time is uniformly mixed, stirring and centrifuging to obtain precipitate, washing to dry the perovskite photocatalyst; and (2) use of the perovskite photocatalyst in catalyzing and degrading sudan red III which is not soluble in water.