Cd0.5Zn0.5S/g-C3N4 (CZS/CN) step-like heterojunction composites were facilely synthesized by annealing a sandwich of cadmium-zinc-thiourea precursors in one pot.The types of the used raw materials and the preparation procedure were simplified as much as possible in this work.The obtained hybrid exhibited enlarged specific surface area and higher separation/transfer efficiency of charge carriers compared to pure Cd0.5Zn0.5 S and g-C3N4,thus exhibited much enhanced photocatalytic efficiency for dye degradation under visible-light irradiation.The interracial charge-transfer mechanism of the formed step-scheme (S-scheme) heterojunction between Cd0.5Zn0.5S and g-C3N4 were carefully investigated and discussed.This work could widen the application prospect of the CdxZn1-xS/g-C3N4 composite and provide new ideas to the design and fabrication of novel heterojunctions with robust photocatalytic performance.