Department of Earth and Environmental Engineering Professor Jae-Young Lee’s joint research team develops a new catalyst to lower the production price of ‘clean hydrogen’
A domestic research team has developed a new manganese-based catalyst that can lower the cost of electrolyzing water to produce high-purity hydrogen (water electrolysis). When replacing the existing expensive precious metal catalyst, eco-friendly hydrogen can be produced at low cost, which is expected to contribute to advancing the hydrogen era.
GIST (Gwangju Institute of Science and Technology) uses a manganese-based catalyst mixed with conductive carbon in a study conducted jointly by Professor Jae-Young Lee’s research team from the Department of Earth/Environmental Engineering with Professor Ki-Young Lee’s research team from the Department of Chemical Engineering at Inha University by controlling the electrical conductivity of the catalyst. ‘
Although the ‘water electrolysis’ method is an eco-friendly hydrogen production method that does not emit greenhouse gases, the high cost of electricity is an obstacle to its practical use. To use hydrogen in a wider and more diversified way, the production cost must be significantly lowered, and therefore, the development of a high-performance catalyst capable of producing hydrogen with less energy is required. Precious metals such as iridium and ruthenium are mainly used for water electrolysis as excellent catalysts for generating oxygenation, but they have a disadvantage in that they are expensive. Therefore, it is important to develop an inexpensive and excellent transition metal-based (nickel, cobalt, iron) hydrogen/oxygen catalyst.
Manganese-based metal oxide is a representative water decomposition catalyst that exists in nature. It has structural diversity, abundant reserves, and non-toxicity, so many studies are being conducted to use it as a water electrolysis catalyst. Existing manganese oxide is generally known to have low electrical conductivity and the oxygen evolution reaction occurs well only in a specific structure (δ-MnO2). Sufficient electrical conductivity is required.
The research team introduced graphitized conductive carbon into the catalyst layer to secure electrical conductivity and improved the oxygen evolution reaction performance of the catalyst layer by repeated electrochemical activation method. As a result, the oxygen evolution reaction activity increased more than 15 times, and when applied to the third-generation anion exchange membrane water electrolysis method to determine the commercial applicability of the developed catalyst, it was found that hydrogen production was possible at a current density 400% higher than that of the existing catalyst. Confirmed.
Professor Jaeyoung Lee of GIST said, “Using inexpensive manganese oxide, we were able to develop a catalyst that can improve water electrolysis performance by increasing the catalyst active point.” In an urgent situation, the significance of this research result is great.”
Professor Ki-young Lee of Inha University said, “This catalyst technology is meaningful in that it has secured the original technology to commercialize manganese oxide as a water electrolysis catalyst. ”
This study, led by Professor Jaeyoung Lee (corresponding author) of GIST School of Earth/Environmental Engineering (corresponding author) and Professor Kiyoung Lee (co-corresponding author) of the Department of Chemical Engineering at Inha University, was conducted by Dr. Gahyeon Ham (first author) and PhD student Jaewon Lee (co-first author). It was supported by the Research Foundation and the Korea Energy Technology Evaluation Institute, and was published online on April 25, 2022 in the Journal of Energy Chemistry, an international academic journal in the field of applied chemistry.