Controllable Synthesis of MoS2/h-CdS/c-CdS Nanocomposites with Enhanced Photocatalytic Hydrogen Evolution Under Visible Light Irradiation

Firstly, h-CdS/c-CdS homojunction was prepared by solvothermal method with controlling the Cd-to-S molar ratio. Then, the MoS 2 /h-CdS/c-CdS nanocomposites were constructed by ultrasonic method with different MoS 2 amount. The experimental results showed that when the molar ratio of Cd and S was 1:1 and the amount of MoS 2 was 1.5 wt%, the MoS 2 /h-CdS/c-CdS nanocomposites exhibited excellent photocatalytic performance for hydrogen evolution under visible light. The total amount of hydrogen evolution was 3753.12 µmol for 5 h, and its average hydrogen evolution rate was 40.79 mmol h −1  g −1 with an apparent quantum efficiency of 38.16% irradiated at 420 nm, which was about 7.3 times when compared with the h-CdS/c-CdS homojunction (Cd:S = 1:8). The enhanced photocatalytic performance of MoS 2 /h-CdS/c-CdS could be attributed to the improved specific surface area and formation of well bonded interface structure, which not only enhanced the response to visible light but also decreased the recombination rates of photogenerated charge carriers. Graphical Abstract