ABSTRACT
Nanosized metal oxide photocatalyst materials for water splitting have emerged as the promising way for hydrogen generation in a low-cost and sustainable way. The characteristics of metal oxide photocatalysts can be fine-tuned by varying their shapes and sizes. The water-splitting performance of a nanomaterial can be easily upgraded by simply tuning the band gap of the photocatalyst. Various researchers have reported investigations on co-relation of crystallinity and morphology of nanomaterials to the water-splitting performance. In general, the nanomaterials with high surface-to-volume ratios are expected to promote facile charge separation/transportation of photogenerated charge carriers. The present chapter reviews the recent development in metal oxide photocatalysts for water splitting and hydrogen generation. The anticipated role of nanosized metal oxide photocatalysts in the viewpoint of its applicability in water splitting has been discussed in brief. The different metal oxide materials, including titanium oxide, zinc oxide, iron oxide, tungsten oxide, bismuth vanadate, and their composites developed for water splitting and current challenges associated with them, have been extensively reviewed. This review also follows a case study on synthesis, characterization, and utilization of mixed-valence Sn3O4 nanomaterials for hydrogen generation under visible light.
