OUC Made New Progress in the Formation Mechanism of Bimetallic Catalysts

The research team led by Prof. Huang Minghua from the School of Materials Science and Engineering, published a paper titled Developing a class of dual atom materials for multifunctional catalytic reactions in Nature Communications.

The development of hydrogen energy is crucial to the dual carbon goals. Hydrogen production through water electrolysis using renewable energy is currently one of the most promising low-carbon methods. The oxidation reaction and hydrogen evolution reaction (HER) are the core processes, involving multiple proton-electron coupling steps. These reactions have relatively slow kinetics, necessitating the development of efficient, stable, and low-cost electrocatalytic materials to enhance their conversion efficiency. Currently, single-atom catalysts, known for their high atomic utilization and tunable coordination environments, have become a research hotspot in the field of electrocatalysis for new energy sources. Bimetallic catalysts, extending from single-atom catalysts, serve as a bridge between single atoms and nanoparticles/nanoclusters, offering significant advantages in synergistically driving complex multi-step catalytic reactions. However, the formation mechanisms of bimetallic catalysts are not yet clear, and universal synthesis methods are still in the exploratory stage.

To address these challenges, researchers led by Prof. Huang Minghua have developed a strategy that enables the atomization and sintering process from metal Co nanoparticles to CoN4 single atoms, and further to Co2N5 dual atoms. This approach enables controlled tailoring of metal configurations at the atomic level and simultaneously offers an ideal platform for exploring the formation mechanisms of dual atoms through its controllable synthesis strategy. The research findings indicate that Co metal atoms can be gradually stripped from nanoparticles and anchored by N atomic sites to form CoN4 single atoms, and then undergo live migration to spontaneously sinter into Co2N5 dual atoms. This strategy can be extended to the preparation of 22 different bimetallic catalysts across the s, p, and d blocks. The Co2N5 dual atom, possessing a specific spin state, achieved an ideal adsorption-desorption equilibrium of the reaction intermediates, displaying exceptional multifunctional activity. This endowed zinc-air batteries with long-term stability of 800 hours and facilitated extended water-splitting operations for over 1000 hours, while also enabling solar energy-driven water-splitting systems to produce hydrogen continuously, both day and night. This universal and scalable strategy provides guidance for the controlled design of efficient and multifunctional bimetallic catalysts in energy conversion technologies.