Professor Jeungku Kang and his research team from the Department of Materials Science and Engineering have participated in a joint research project with Sungkyunkwan University, UNIST, Pusan National University, Berkeley University, and Caltech. In the study, they successfully utilized a technology that controls the gap between copper atoms to convert carbon dioxide, a greenhouse gas, into high-value fuel such as ethylene. 

The research team introduced an atomic-level catalyst control technology to overcome the limitations of the pre-existing nanoparticle-based catalysts, resulting in an 80% increased ethylene production rate from carbon dioxide. The main interest of this research was the unprecedented use of the atomic gap as the main factor in designing the catalyst. At the same time, the production of unwanted methane, which can be easily obtained from natural gas, was completely suppressed experimentally. The principle of the catalyst’s activity depending on the atomic gap was theoretically investigated using quantum mechanical calculation technology.

The research was published in the Advanced Energy Materials journal on March 10 under the title “Atomic-Scale Spacing between Copper Facets for the Electrochemical Reduction of Carbon Dioxide”.

This development of an efficient carbon dioxide conversion technology will help reduce the atmospheric carbon dioxide concentration of our planet and provide another way to produce fuels or compounds useful for the industry. Various transition metal-based electrochemical catalysts have been developed to convert carbon dioxide in the past, but copper is the only element capable of producing a hydrocarbon-based fuel such as ethylene. However, until now, copper catalysts resulted in low efficiency due to their slow reaction rates and product selectivity. 

In order to improve the efficiency of the copper catalyst, the researchers carefully controlled the reduction reaction of oxidized copper electrochemically to create a narrow gap of less than one nanometer between copper crystal faces. Within this gap, researchers optimized the adsorption energy of the carbon dioxide reduction reaction intermediate to maximize the activity of the reaction. At the same time, it was found that high-value compounds such as ethylene were efficiently produced by inducing carbon-carbon bonds.

The atomic gap principle, a novel activator proposed in the study, is significant in that it can be extended to various fields in electrochemical catalyst research.