Recent advances and demonstrated potentials for clean hydrogen via overall solar water splitting

ABSTRACTSolar water splitting can potentially play a significant role in the future, sustainable and carbon-neutral energy infrastructure - by generating hydrogen as a green fuel from renewable sources and liquid-fuels via carbon-dioxide reduction. Hydrogen has higher gravimetric energy-yield compared to most of the conventional fossil fuels, is storable and transportable on demand. With the prospective green hydrogen economy in mind, considerable efforts have been made in the quest for a stable and efficient photocatalyst/photoelectrode which can eventually lead towards the realization of large-scale hydrogen production system. This snapshot review provides a summary of the basic principles and challenges associated with unassisted overall water splitting, and highlights the recent technological advancements made on the device and system designs on lab-scale - to improve different performance metrics, i.e., efficiency, stability, scalability and large-scale prototypes with demonstrated potentials for future developments.