▎ 摘　　要

NOVELTY - A multicomponent composite catalyst is prepared by reducing graphene oxide (GO) in presence of a polymeric ionic liquid (PIL), performing ion exchange reaction of obtained PIL/reduced graphene oxide (rGO) complex, immobilizing carboxyl group (B12) onto the surface of the obtained PIL/rGO sheet, obtaining B12-PIL/rGO complex, dispersing B12-PIL/rGO complex and rhodamine B (RhB) in deionized water, stirring at room temperature, centrifuging, repeatedly washing obtained solid with deionized water until the supernatant is colorless, and vacuum-drying. USE - Multicomponent composite catalyst is used for degrading organic halide e.g. 2,2-bis(4-chlorophenyl)-1,1,1-trichloroethane in visible light (all claimed). ADVANTAGE - The multicomponent composite catalyst efficiently degrades organic halide under visible light. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for usage of multicomponent composite catalyst in degradation of organic halide under visible light.