Migration of Au Nanoparticles on a TiO2(110) Surface in Reactant Gases Observed by In-Situ STM at Elevated Temperatures

摘要

Behavior of Au nanoparticles on a TiO2(110) cross-linked (1×2) surface under the atmosphere of reactant gases (CO, O2, CO+O2) at elevated temperatures was observed by scanning tunneling microscopy (STM). Au nanoparticles were grown larger by the thermal treatment in O2 or O2+CO atmosphere. In-situ STM in such oxidative atmosphere revealed that the migration of Au nanoparticles occurs associated with the oxidation of a TiO2 surface from cross-linked (1×2) to (1×1) structure. These results imply that the Au—Ti interaction is made unstable in real atmosphere of catalytic reactions, even if the unsaturated Ti species act as the initial nucleation sites. [DOI: 10.1380/ejssnt.2011.234]