In-situ construction of Mo3S4/Cd0.5Zn0.5S heterojunction: An efficient and stable photocatalyst for H2 evolution

In this work, Mo3S4/Cd0.5Zn0.5S heterojunction with abundant porosity was in-situ synthesized by one-step hydrothermal method. Characterization results clearly indicate that the composite material are composed of nanoparticles with an average particle diameter about 65 nm and abundant inter-particle pores are present in between. The XPS analysis found that when Mo3S4 was introduced, the XPS peak positions of Cd2+ and Zn2+ were shifted from the XPS peak positions of Cd2+ and Zn2+ in pristine Cd0.5Zn0.5S, which indicates that there is an interaction between Mo3S4 and Cd0.5Zn0.5S at the interface. Subsequently, the Mo3S4/Cd0.5Zn0.5S (72.1 mmol h−1 g−1) heterojunction can achieve much higher photocatalytic hydrogen production rate than the pristine Cd0.5Zn0.5S (7.54 mmol h−1 g−1), and even higher than Cd0.5Zn0.5S (56.44 mmol h−1 g−1) loaded with the noble metal Pt (2.0%), indicating that heterojunction can effectively enhance photocatalytic activity. In addition, the improvement in photocatalytic activity of Mo3S4/Cd0.5Zn0.5S is highly related with enhanced absorption and utilization of light due to the presence of the inter-particle pores which inhibit recombination of electron-hole pairs, promote charge separation and accelerate the migration of photogenerated carriers.