The future of solar-driven water splitting

Solar-driven water splitting offers a direct path to green hydrogen by using sunlight to split water into hydrogen and oxygen, enabling flexible energy storage and hydrogen fuel production. Yet, turning lab-scale demonstrations into widespread deployment requires overcoming intertwined fundamental and engineering challenges. This Voices piece gathers researchers from around the world who work on photocatalytic, photoelectrochemical, and biophotoelectrochemical water splitting to discuss bottlenecks, promising strategies, and the tools most helpful for advancing solar fuels production. They address design principles for materials and devices, emerging configurations and benchmarking concepts, pathways to commercialization, and how related catalytic processes and adjacent fields can guide sustainable hydrogen evolution. What becomes clear is that achieving scalable solar-driven hydrogen production will require integrated, multi-disciplinary efforts that bridge responsible discovery and deployment.