Efficient photocatalytic H₂ production via rational design of synergistic spatially-separated dual cocatalysts modified Mn_0.5Cd_0.5S photocatalyst under visible light irradiation

Noble metal-free highly efficient cocatalysts are very important for cost efficient hydrogen fuel production. While most studies concentrate on single cocatalyst photocatalytic systems. Here, we report on the synthesis of Mn_0.5Cd_0.5S photocatalyst hetero-architecture with synergistic spatially separated dual cocatalysts Cu_2−xS and MoS₂ for highly efficient photocatalytic H₂ production. Through tactfully utilizing Cu_2−xS/Mn_0.5Cd_0.5S nanoscale p-n junction to promote efficient transfer of photo-generated holes to Cu_2−xS and MoS₂ can be located exactly on the different positions where the photo-generated electrons must go through by photo-reduction of (NH₄)₂MoS₄. Cu_2−xS can be an oxidation active site to assemble photo-generated holes and MoS₂ can capture and transport the photon-generated electrons. Therefore the photo-induced carriers can be efficiently separated and transferred to take part in photocatalytic reactions. The prepared Cu_2−xS (0.015)/Mn_0.5Cd_0.5S/MoS₂ (3 wt%) photocatalyst shows the highest H₂ production rate of 687.62 μmol/h, which exceeds the rate of Mn_0.5Cd_0.5S and Mn_0.5Cd_0.5S loaded with Cu_2−xS or MoS₂ alone by 22, 1.7 and 3.48 times, respectively. This work provides a new thought to design efficient spatially separated and synergistic dual cocatalysts modified photocatalysts for H₂ production.