Vanadium tetrasulfide as an earth-abundant and noble-metal-free cocatalyst for a solar-to-hydrogen conversion reaction

Designing non-precious metal cocatalysts with high surface area that facilitate interfacial charge separation is a significant challenge in solar-to-hydrogen energy conversion reactions. Herein, we report a heterostructured photocatalytic system consisting of highly dispersed oxygen-doped VS4 nanoparticles on a one-dimensional network of cadmium sulfide nanorods. Structural and morphological investigations revealed that the VS4 nanoparticles created Schottky heterojunctions for efficient charge transfer and provided abundant catalytic active sites. Additionally, the higher work function of VS4 enabled a superior transfer of photoinduced charge carriers from CdS to all accessible VS4 NPs, realizing excellent visible photocatalytic hydrogen evolution activity. As a result, the obtained CdS/VS4 heterostructures exhibited an outstanding catalytic activity of 5846 mu mol g(-1) h(-1), which was five times higher than that of pure CdS nanorods. Moreover, the optimized CdS/VS4 photocatalytic system with an ultralow amount of the VS4 cocatalyst outperformed the Pt and MoS2 cocatalysts in the CdS-Pt and CdS-MoS2 photocatalytic systems, respectively. This study demonstrates a breakthrough in the exploration and development of non-noble-metal-based cocatalysts for efficient charge separation in solar-to-fuel conversion reactions.