Korean researchers have developed a new catalyst design technology that can improve the performance of batteries and hydrogen fuel cells while reducing energy loss.
KAISTannounced on the 1st of June that a research team led by Professor Seung Jun Hwang of the Department of Chemistry, through joint research with Professor Jaeyune Ryu’s team from the Department of Chemical and Biological Engineering at Seoul National University , has proposed a new catalyst design strategy that can improve the efficiency of key reactions that generate electricity inside batteries and fuel cells.
A catalyst is a material that helps chemical reactions occur faster and more efficiently. In batteries or fuel cells, it plays a role in facilitating the reactions that generate electricity. Catalysts usually consist of a central metal and a molecular structure surrounding it.
In previous studies, methods mainly involved changing the type of metal from iron (Fe) to cobalt (Co) or nickel (Ni), or newly designing the molecular structure around the metal, known as the ligand, to improve reaction performance. In simple terms, this approach changes the material or shape of the catalyst itself to make it react better. By contrast, this study is differentiated by showing that performance can be improved simply by adjusting the electrical environment around the catalyst, without greatly changing the catalyst itself.
To use a simple analogy, this study can be compared to “making cooking work better by adjusting the kitchen environment instead of changing the cooking tool itself.” Previous catalyst research was closer to changing the material of a frying pan or redesigning its shape. By contrast, this study keeps the frying pan the same and precisely adjusts the surrounding temperature and airflow so that the food cooks better. In other words, the core of this research is that the team made the reaction occur more efficiently by adjusting the electrical environment around the catalyst, rather than creating an entirely new catalyst.
The research team confirmed that placing “cations (+)” around the catalyst to create a very small electric field can induce the reaction needed to generate electricity to occur more stably. In particular, the proportion of the desired reaction increased from the previous level of about 12% to as high as 52%.
Through this, the research team confirmed that the desired reaction can be efficiently induced with less energy than before. This is expected to contribute to improving the efficiency, lifespan, and stability of batteries and hydrogen fuel cells.
The oxygen reduction reaction (ORR, a key reaction in which oxygen receives electrons to generate electricity) examined in this study is a core reaction that generates electricity in next-generation energy devices such as fuel cells for hydrogen vehicles (Fuel Cell, a device that produces electricity through a chemical reaction between hydrogen and oxygen) and metal-air batteries (Metal-Air Battery, a next-generation battery that stores and produces electricity using metal and oxygen in the air).
The research team also believes that this principle can be applied to catalyst technologies that convert carbon dioxide (CO₂) or hydrogen into other useful substances, and that it can therefore be used in the development of various next-generation energy catalysts, including carbon dioxide reduction technologies and eco-friendly hydrogen production technologies.
Professor Seung Jun Hwang stated, “This study demonstrates that reaction properties can be precisely controlled solely through the surrounding electrical environment, without changing the structure of the catalyst itself,” adding, “We expect it to present a new direction for developing next-generation batteries, fuel cells, and eco-friendly energy catalyst technologies.”
This research, with POSTECH chemistry doctoral students Hwi Yul Jo and Vom Kang and KAIST postdoctoral researcher Dongyoung Kim as co-first authors, was published online on April 12 in the Journal of the American Chemical Society (JACS).
※ Paper title: “Localized Cation Unlocks Unique Activity–Selectivity Trends in Molecular Oxygen Reduction Catalysis,” DOI: pubs.acs.org/doi/10.1021/jacs.5c18246
Lead author information: Hwi Yul Jo (doctoral student, POSTECH), Vom Kang (integrated master’s–PhD student, POSTECH), Dongyoung Kim (postdoctoral researcher, KAIST)
This research was supported by the Samsung Science and Technology Foundation, the National Research Foundation of Korea’s “Hanwoomul” Basic Research Program, and the Nano and Material Technology Development Program.