Solar-to-chemical energy conversion is one of the most promising solutions to sustainable energy and environmental remedy issues, which has attracted increasing attention both in fundamental research and industrial application. In this review, we choose the key reaction in solar-to-chemical conversion, photocatalytic water splitting, as an example to introduce fundamental scientific advances in this field. We focus on the mechanism of photocatalytic water splitting, light-absorbing materials, photogenerated charge separation, dual-cocatalyst, Z-scheme and technical and economic evaluation of hydrogen production for potential applications. Finally, we present conclusion remarks and future directions of photocatalytic water splitting for solar energy conversion.

hydrogen production  /  photocatalytic water splitting  /  cocatalyst  /  photogenerated charge separation