Non-noble metals applied to solar water splitting

The generation of hydrogen (H-2) induced by solar water splitting over semiconductors has been regarded as one of the most promising strategies for providing clean and renewable energy sources for future energy sustainability. The key to achieving high solar-to-chemical-energy conversion efficiency is the design of efficient structures with high charge separation and transportation; thus, the development of inexpensive and functional nanomaterials has become quite necessary. Photocatalysts based on non-noble metals have great potential as substitutes for noble metal-based catalysts for H-2 generation from photocatalytic (PC) and/or photoelectrochemical (PEC) water splitting. In this review, we present the recent progress on non-noble metal-based nanostructures using in PC and/or PEC water splitting and reveal their underlying roles in affecting the behavior of charge carriers in specific reactions. This review should bring new insight and inspire further innovative work on designing non-noble metals involved in solar water splitting.