Frontiers in Science Lead Article
Published on 03 Dec 2024
Experts delved into photocatalytic water splitting at a virtual Frontiers Forum Deep Dive session on 26 February 2025.
Sunlight-driven technologies, including green hydrogen production and artificial photosynthesis, could offer sustainable, decentralized solutions to global energy challenges like clean cooking, deforestation, and carbon emissions, highlights Prof Johan A. Martens, KU Leuven, Belgium.
Scaling photocatalytic hydrogen production requires improved efficiencies, investments in sustainable energy infrastructure, and stringent safety and environmental standards, assert Drs Markus Antonietti and Christian M. Pelicano, Max Planck Institute of Colloids and Interfaces, Germany.
An international regulatory framework, including policy support for research, infrastructure, safety, and market development, could position green hydrogen as a global energy commodity, argues Dr Leticia M. Torres-Martínez, Universidad Autónoma de Nuevo León, México.
The urgent need for humanity to reduce its dependence on fossil fuels and shift to renewable fuels has driven interest in the large-scale implementation of photocatalytic water splitting using solar energy to produce green hydrogen.
Near-perfect conversion yield for photocatalytic water splitting was achieved under irradiation using ultraviolet light and the feasibility of scaling up photocatalytic solar hydrogen production by photocatalyst sheet was demonstrated using a 100m² outdoor prototype panel reactor system. These breakthroughs provide key steps toward large-scale implementation.
Proactive development of visible light-responsive photocatalysts with high solar-to-hydrogen energy conversion efficiencies, and improvement and further scale-up of photocatalytic water-splitting systems, are priorities for their large-scale deployment to be competitive with existing fuel production technologies. In this regard, photocatalyst sheets are a game-changer.
Safety is of utmost importance when handling oxyhydrogen gas that can result from photocatalytic water splitting; risk can be reduced to an acceptable level by ensuring the safety of the entire process and complying with relevant laws and regulations. An alternative to the production of oxyhydrogen gas is the separate generation of hydrogen and oxygen, which is inherently safe.
An accrediting organization composed of experts with a deep understanding of photocatalysis would be instrumental in streamlining the hydrogen production process and certifying reported solar-to-hydrogen energy conversion efficiencies, thereby supporting further scale-up and implementation of photocatalytic water-splitting systems.
A summary of the lead article in a Q&A format, with infographics and a video.
A version of the lead article written for—and peer reviewed by—kids aged 8-15 years.
Crucial advances in technology could allow us to harness the power of the sun to split water into hydrogen and oxygen and siphon off renewable fuel.
More work is needed if we are to break the 5% efficiency barrier, but the team is confident this will be possible in the future.
Scientists from Japan have developed new materials and methods to increase the efficiency and safety of a proof-of-concept green hydrogen reactor.
A reactor that splits water to make hydrogen using sunlight and catalysts, without conversion to electricity in between, has operated successfully for three years.
Follow the science, follow Frontiers in Science