▎ 摘　　要

NOVELTY - Preparing cadmium sulfide/copper oxide/graphene photocathode protective composite material comprises (i) dispersing graphene oxide in copper nitrate solution, adding urea solution, stirring, carrying out hydrothermal reaction, cooling, filtering, drying filter cake and calcining under nitrogen atmosphere to obtain copper oxide/graphene composite material, and (ii) dispersing copper oxide/graphene composite material prepared in step (i) in aqueous solution of cadmium salt, adding thiourea, stirring under ice bath, adjusting the pH value, then adding aqueous solution of sodium sulfide, stirring under dark condition, filtering, washing filter cake and drying to obtain cadmium sulfide/copper oxide/graphene composite material. USE - The composite material is useful for anti-corrosion metal under dark environment (claimed). DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for cadmium sulfide/copper oxide/graphene photocathode protective composite material is obtained by above method.