Japanese researchers from Shinshu University have developed a promising new method for producing hydrogen fuel from water using sunlight, a breakthrough that could make hydrogen production more sustainable and cost-effective.
Currently, most hydrogen is produced from natural gas, a process reliant on fossil fuels. The new method offers a more sustainable approach, using sunlight to split water into hydrogen and oxygen. While this concept isn’t new, existing methods have struggled with efficiency. Many rely on single-step photocatalysts, which convert solar energy into hydrogen with low energy yields.
The Japanese researchers utilized a more sophisticated two-step excitation system, where one photocatalyst generates hydrogen, and another produces oxygen. This method has shown greater promise for improving solar-to-hydrogen conversion efficiency.
The team, led by Professor Kazunari Domen and Dr. Takashi Hisatomi, achieved a significant milestone by operating a 100-square-meter reactor for three years. Remarkably, the system performed better under real-world sunlight than in laboratory conditions. Using an ultraviolet-responsive photocatalyst, the solar energy conversion efficiency was about 1.5 times higher in natural sunlight.
Despite these successes, the technology is still in its early stages. Under standard simulated sunlight, the current conversion efficiency remains at just 1%. The team believes surpassing the 5% efficiency threshold will require the development of more effective photocatalysts and the construction of larger experimental reactors.
Prof. Domen emphasized the critical need to improve solar-to-chemical energy conversion efficiency. If achieved, it could pave the way for scalable production technologies, gas separation processes, and infrastructure development. This progress could shift perceptions of solar energy and expedite the establishment of regulations and policies to support solar fuel technologies.
The study was published in Frontiers in Science.