Clean hydrogen in minutes with microwave energy innovations

Tokyo, Japan (SPX) Jan 22, 2025
A pioneering research team at POSTECH, led by Professor Gunsu S. Yun and doctoral candidate Jaemin Yoo from the Department of Physics and Division of Advanced Nuclear Engineering, alongside Professor Hyungyu Jin and doctoral candidate Dongkyu Lee from the Department of Mechanical Engineering, has unveiled an innovative microwave-based technology for clean hydrogen production. This approach addresses critical challenges in the field while offering new insights into the underlying mechanisms. Their findings, featured on the Inside Front Cover of the Journal of Materials Chemistry A, represent a significant advance in sustainable energy development.

Clean hydrogen, recognized for its zero carbon emissions, is increasingly vital as the global energy landscape shifts from fossil fuels. However, current hydrogen production methods face notable obstacles. Traditional thermochemical processes, which utilize oxidation-reduction reactions involving metal oxides, demand exceptionally high temperatures of up to 1,500 C. These extreme requirements make such methods energy-intensive, expensive, and difficult to scale effectively.

To overcome these barriers, the POSTECH researchers explored the potential of microwave energy-commonly associated with household cooking-as a transformative tool for chemical reactions. They demonstrated that microwaves could significantly lower the reduction temperature of Gd-doped ceria (CeO2), a standard material for hydrogen production, to below 600 C-a reduction of over 60 percent. Additionally, microwave energy replaced 75 percent of the thermal energy traditionally required for this process, marking a major step forward in sustainable hydrogen production.

A key innovation was the rapid creation of "oxygen vacancies"-structural defects in materials critical for water splitting into hydrogen. Conventional methods typically require hours at extreme temperatures to form these vacancies. By utilizing microwave energy, the POSTECH team achieved comparable results within minutes and at temperatures below 600 C. Their findings were further supported by a thermodynamic model that clarified the underlying microwave-driven reaction mechanism.

Professor Hyungyu Jin emphasized the importance of these results, stating, "This research has the potential to revolutionize the commercial viability of thermochemical hydrogen production technologies. It will also pave the way for the development of new materials optimized for microwave-driven chemical processes." Professor Gunsu Yun added, "Introducing a new mechanism powered by microwaves and overcoming the limitations of existing processes are major achievements, made possible through the close interdisciplinary collaboration of our research team."

This study received funding from the Circle Foundation's Innovative Science and Technology Program, the Ministry of Science and ICT's Mid-Career Researcher Program, POSTECH's Basic Science Research Institute, and the Ministry of Trade, Industry, and Energy.

Research Report:Thermodynamic assessment of Gd-doped CeO2 for microwave-assisted thermochemical reduction