| AVS 66th International Symposium & Exhibition | |
| Fundamental Discoveries in Heterogeneous Catalysis Focus Topic | Wednesday Sessions |
| Session HC+OX+SS-WeA |
| Session: | Metal-Support Interactions Driving Heterogeneously-Catalyzed Reactions |
| Presenter: | Satoru Takakusagi, Hokkaido University, Japan |
| Authors: | S. Takakusagi, Hokkaido University, Japan L. Bang, Hokkaido University, Japan D. Kido, Hokkaido University, Japan Y. Sato, Hokkaido University, Japan K. Asakura, Hokkaido University, Japan |
| Correspondent: | Click to Email |
Polarization-dependent total reflection fluorescence (PTRF)-XAFS is a powerful technique which can determine 3D structure of highly dispersed metal species on a single-crystal surface by measuring polarization-dependent XAFS of the metal species. To obtain atomic-level understanding of metal/oxide-support interaction in heterogeneous catalysis, we have determined the precise 3D structures of single metal atoms and metal clusters deposited on single-crystal oxide surfaces such as TiO2(110) and Al2O3(0001) by UHV PTRF-XAFS apparatus.[1]
Recently we have constructed a new apparatus which enables us to measure PTRF-XAFS of active metal species dispersed on a single-crystal oxide surface under working condition. A compact vacuum chamber which works both as PTRF-XAFS cell and batch-type reactor was designed and constructed. The sample can be transferred without exposure to air from another UHV chamber where the sample preparation (ion sputtering, annealing and metal deposition) and its surface characterization (LEED, XPS) are carried out. The sample in the compact chamber can be heated at high temperatures (< 700 ℃) in the presence of reactant gases (typically 10~100 Pa), which makes the operando PTRF-XAFS measurements possible. Thus 3D structure-activity relationship of the active metal species on an oxide surface in heterogeneous catalysis can be obtained. We will show the details of the operando PTRF-XAFS technique and its application to CO oxidation on a Pt/Al2O3(0001) surface.
(References)
[1] S. Takakusagi et al., Chem. Rec. 18 (2018) 1, J. Phys. Chem. C120 (2016) 15785, Top. Catal. 56(2013) 1477, Phys. Chem. Chem. Phys. 15(2013) 14080.