Regulation of morphology and charge transfer mechanism: Oxygen vacancy-rich Mn0.2Cd0.8S/CoMoO4 S-type heterojunction promoting photocatalytic hydrogen production through hydrothermal in-situ synthesis.

The development of efficient photocatalysts is a very interesting topic for sustainable hydrogen production using solar energy. In this paper, Mn 0.2 Cd 0.8 S was loaded on CoMoO 4 nanorods by in-situ solvothermal method. Through morphological control, two rod-shaped elemental materials were loaded in situ to construct a composite with a ball shaped bouquet structure. The Mn 0.2 Cd 0.8 S/CoMoO 4 photocatalyst with enriched oxygen vacancies was synthesized by high-temperature annealing. It is worth noting that by constructing an heterojunction, the Mn 0.2 Cd 0.8 S/CoMoO 4 photocatalyst exhibits high catalytic activity and stability. The optimal H 2 production rate of Mn 0.2 Cd 0.8 S/CoMoO 4 was 7.04 mmol·g−1·h−1. Surprisingly, the hydrogen production rate of the composite was 35.88 times that of CoMoO 4. Density functional theory (DFT) calculations showed that Mn 0.2 Cd 0.8 S/CoMoO 4 has electron attraction ability and strong conductivity. X-ray photoelectron spectroscopy (XPS) confirmed the charge transfer path of the heterojunction between Mn 0.2 Cd 0.8 S and CoMoO 4 , which greatly promoted the spatial charge separation. This work provides a reference for combining heterojunction design with defect engineering to achieve efficient conversion of solar energy to chemical energy. • Mn 0.2 Cd 0.8 S was loaded on CoMoO 4 nanorods by in-situ solvothermal method. • Design composite catalyst from the two aspects of morphology and band structure. • Mn 0.2 Cd 0.8 S/CoMoO 4 with enriched oxygen vacancies was synthesized. • The recombination of photo-generated carriers was effectively suppressed. [ABSTRACT FROM AUTHOR]