Z-scheme structure SnS2–Au–CdS with excellent photocatalytic performance for simultaneous removal of Cr(VI) and methyl orange

Abstract

A highly efficient Z-scheme photocatalyst SnS2–Au–CdS was fabricated by photoreduction and thiourea medium deposition methods. It was found that Au nanoparticles were successfully anchored on the surface of SnS2, and CdS nanoparticles were further deposited on the surface Au nanoparticles by the strong interaction of S–Au. Compared to SnS2, CdS, SnS2–Au, and SnS2–CdS, Z-scheme structure SnS2–Au–CdS shows the best photocatalytic performance for methyl orange (MO) degradation and Cr(VI) reduction under visible light irradiation. The outstanding photocatalytic performance of SnS2–Au–CdS can be ascribed to the special Z-scheme structure which not only improves the separation of photogenerated charge carriers but also preserves its high redox ability. In addition, SnS2–Au–CdS exhibited synergistic effects in photocatalytic removal of Cr(VI) and MO.