讲座主题：Operando Surface Science Studies for Designing Advanced Nanocatalysts
主讲人： Jeong Y. Park KAIST Endowed Chair Professor at the Department of Chemistry
邀请人： Yabing Qi
时间： 2025.07.23 15:30 ~ 2025.07.23 16:30
地点： Room 200, Yue-Kong Pao Library's Annex
摘要： Clarification of the nature of active sites at both of solid-gas and solid-liquid interfaces has been a long-standing question in surface chemistry, holding paramount significance in crafting innovative catalytic materials that demand minimal energy consumption. A bimetallic Pt alloy or mixed catalyst is an excellent platform to uncover the contentious role of the metal–metal oxide interface because the alloyed transition metal can coexist with the Pt surface layer in the form of an oxidized species on the bimetal surface during catalytic reactions. The real-time imaging of catalytically reactive atomic sites using operando surface techniques including ambient pressure scanning tunneling microscopy can reveal the nature of reactive sites on the catalytic surfaces. In this talk, I present in-situ observation results of structural modulation on Pt-based bimetal catalysts and mixed catalysts and its impact on the catalytic activity. We utilized PtNi, and PtCo that includes both of single crystal and nanoparticle surfaces as model catalysts, and showed the coexistence of Pt and metal oxide leads to the enhancement of catalytic activity, indicating these metal-oxide interfaces provide more efficient reaction path for CO oxidation. The mixed catalysts composed of Pt nanoparticles and the mesoporous cobalt oxide exhibit the enhancement of catalytic activity while Pt is encapsulated by the oxide thin layers forming the reactive metal-oxide interfaces. Our investigation employs various operando surface techniques, including ambient pressure scanning tunneling microscopy/ atomic force microscopy, ambient pressure X-ray photoelectron spectroscopy, and environmental transmission electron microscopy. Our findings reveal that the presence of metal and metal oxide coexisting at the interface enhances catalytic activity, suggesting that these metal-oxide interfaces offer more efficient reaction pathways for CO oxidation. Notably, mixed catalysts comprising Pt nanoparticles and mesoporous cobalt oxide demonstrate increased catalytic activity when Pt is encapsulated by oxide thin layers, forming reactive metal-oxide interfaces. This principle can be applied to non-Pt bimetallic catalysts including AuCu, and AuPd. In addition, we address the fundamentals of the electrocatalytic process and on locating the real active sites at the solid-liquid interface by utilizing in situ electrochemical scanning tunneling microscopy. Overall, our findings emphasize the substantial importance of metal-oxide interfaces and charge transfer across these interfaces in surface reactions during heterogeneous catalysis, offering the potential for the intelligent design of catalytic materials with minimum energy cost.
主讲人简介 ：
Jeong Young Park is KAIST Endowed Chair Professor at the Department of Chemistry and Adjunct Professor at the Department of Physics, Korea Advanced Institute of Science and Technology. He has carried out cutting-edge research in the fields of surface science, nanoscience, and catalysis. His research focuses on atomic-scale structure and properties of surfaces and nanomaterials for applications in electronics, energy conversion, catalysis, tribology, and environmental science. Prof. Park has authored 340 peer-reviewed papers and book chapters in international journals, and wrote one book in the field of surface science, nanoscience, and catalysis. The number of citations is 20600 with h index of 70, according to Google Scholar citation. He obtained award from Ministry of Science and ICT, Republic of Korea in 2023 and award the Fellow from Korean Academy of Science and Technology in 2023. Prof. Park also is the associate editor of Surface Science and Technology (Springer).
