Plate-on-plate structured MoS2/Cd0.6Zn0.4S Z-scheme heterostructure with enhanced photocatalytic hydrogen production activity via hole sacrificial agent synchronously strengthen half-reactions.

The practicable technology for producing hydrogen energy was mainly photocatalytic water splitting. Recently, heterostructural photocatalysts have attracted much attention due to its unique band structures and interfacial interactions. Herein, plate-on-plate MoS2/Cd0.6Zn0.4S heterostructure was rationally designed and fabricated by a simple strategy. It was revealed that Zn-doping content in the Cd0.6Zn0.4S solid solution as well as the mass ratio of MoS2 in the MoS2/Cd0.6Zn0.4S heterostructure can significantly affect the photocatalytic hydrogen evolution reaction (HER) activity. Especially, when Zn doping content is 40 % and the mass ratio of MoS2 is approximately 0.8 % (0.8 % MoS2/Cd0.6Zn0.4S), it exhibits the highest hydrogen production (47.68 µmol·g-1 at 2.5 h) without sacrificial agents. When Na2S/Na2SO3 is employed as sacrificial agent, its HER activity reaches 13466.50 µmol·g-1·h-1, 1.3 folds higher than Cd0.6Zn0.4S. The boosted HER activity of the Z-scheme MoS2/Cd0.6Zn0.4S heterostructure was ascribed to the greatly improved separation efficiency of photogenerated carriers. Most importantly, studies have revealed that the existence of sacrificial agents (Na2S/Na2SO3) can not only accelerate the kinetics of oxidation half reaction, but also synchronously strengthen HER half-reactions. The present work reveals a facile strategy for construction of Z-scheme heterostructures for efficient hydrogen evolution via hole sacrificial agent synchronously strengthen half-reactions.