Atomic-scale interface dynamics for Pt nanoparticles on SrTiO₃ (001)

Pt particles were grown on single-crystal SrTiO₃ (001) surface using pulsed laser deposition. The Pt/SrTiO₃heterostructure was characterized using X-ray standing wave (XSW) excited photoelectron spectroscopy (XPS). After measuring XSW excited core-level photoelectron emission, the atomic-scale interface 3D maps were plotted for all the interface atoms. The Pt and O atoms at the interface change occupation dependent on the oxidization process. Pt atoms also move upwards. Notably, after oxidization process, O atoms prefer to form TiO₂ double layer at the interface and Pt-O bonds form at the top of O atoms. Strong metal-support interaction is confirmed at the interface through comparing the as-deposited and oxidated states. This approach would be beneficial to understand the strong metal-support interaction dynamically in catalysis reactions, especially at the metal-support interface.