Regensburg 2022 – wissenschaftliches Programm
O 3.3: Vortrag
Montag, 5. September 2022, 11:15–11:30, H4
Comparison study of different transition metals on two TiO2 model supports: anatase TiO2(101) and rutile TiO2(110) — •Lena Puntscher1, Kevin Daninger1, Panukorn Sombut1,2, Matthias Meier2, Michael Schmid1, Cesare Franchini2, Ulrike Diebold1, and Gareth S. Parkinson1 — 1Institute of Applied Physics, TU Wien, Austria — 2Faculty of Physics, University of Vienna, Vienna, Austria
Single-atom catalysis (SAC) offers an opportunity to minimize the amount of precious catalyst material required for traditional heterogeneous catalysis and to heterogenize reactions presently requiring homogeneous catalysis. Unravelling how metal atoms bind to oxide supports is crucial for a better understanding of the SACs catalytic properties. Using STM and XPS, we compare the adsorption geometry and stability of several transition metals (Pt, Rh, Ir and Ni) on TiO2 model supports: anatase TiO2(101) and rutile TiO2(110), and the influence of water on the dispersion of these systems. While most of the metals rapidly sinter on both surfaces, there are a few exceptions: Ir forms stable adatoms on the anatase support. Ni is much more dispersed when water vapor is added to the deposition and a very low coverage of Pt single atoms can be stabilized in oxygen vacancies formed on rutile (110), which are only stable in UHV conditions. This study points out the importance of metal-support interaction and the surprisingly different behaviour of the transition metals on TiO2 model supports.