“…Some reports found in the literature discuss the utilization of metal oxides for thin film preparation. [58][59][60] Gopinath's research group reported that, hydrogen evolution from a thin film formed of 1 mg of TiO 2 is 11-12 times higher than that from 25 mg of TiO 2 catalyst by the particulate method. 61 In the present review, we focus on recent advances in transition metal chalcogenide catalysts for the hydrogen evolution reaction, the fundamentals of photocatalytic, electrocatalytic and photo-electrocatalytic reactions, optimization of the bandgap to maximize the harvesting of solar light, and the progress of surface modification to increase the surface-active sites for hydrogen adsorption.…”