Research illustration of a high-efficiency dual hydrogen production system powered solely by solar energy. (Image courtesy of Ulsan National Institute of Science and Technology )
ULSAN, South Korea, April 17, (Korea Bizwire) — In a breakthrough for sustainable energy, researchers at the Ulsan National Institute of Science and Technology (UNIST) have developed a new technology that produces hydrogen using only sunlight and sugarcane waste—without any external power source.
Professors Ji-Wook Jang and Kwan-Yong Seo of the Department of Energy and Chemical Engineering, along with Professor Seung-Ho Cho of the Department of Materials Science and Engineering, announced on Wednesday that they have successfully created a photoelectrochemical system that combines biomass-derived chemicals with silicon photoelectrodes to generate hydrogen.
This system outperforms the U.S. Department of Energy’s commercialization benchmark by a factor of four in terms of hydrogen production rate.
Hydrogen is considered a next-generation fuel for its zero greenhouse gas emissions when burned and its energy density—2.7 times higher than gasoline by weight. However, most hydrogen today is extracted from natural gas, a process that emits significant amounts of carbon dioxide.
To solve this, the UNIST team devised a method that uses furfural, a compound extracted from sugarcane bagasse (the fibrous residue left after juice extraction), as a biomass input. In the system, furfural undergoes oxidation at a copper electrode, producing hydrogen and yielding a high-value byproduct called furoic acid. Simultaneously, water is split into hydrogen at the opposing silicon photoelectrode.
This dual-reaction setup theoretically doubles the hydrogen production rate compared to conventional systems. Silicon photoelectrodes, known for generating a high density of photo-induced electrons, traditionally require external voltage due to their low photovoltage. However, the oxidation of furfural helps balance the system’s voltage, eliminating the need for additional power.
To enhance performance and durability, the researchers used an interdigitated back contact (IBC) structure to reduce internal voltage losses and encapsulated the photoelectrode in nickel foil and glass layers to protect it from electrolytes—improving the system’s long-term stability.
“This technology could significantly boost the cost-effectiveness of solar hydrogen and offer a competitive alternative to fossil fuel-derived hydrogen,” said Professor Jang.
The study was published on March 19 in the journal Nature Communications and was supported by the Ministry of Trade, Industry and Energy and the Korea Institute of Energy Technology Evaluation and Planning.
Kevin Lee (kevinlee@koreabizwire.com)
