SURFACE OXIDE-FILMS AND H2/CO CHEMISORPTION AT THE RU/TIO2 INTERFACE - STUDIES WITH A MODEL PLANAR CATALYST

The properties of high temperature treated (HTT) films of titanium oxide on Ru(0001) have been examined by electron spectroscopy, LEER, and CO/H, chemisorption. Starting with as-deposited TiOx, films, surface-to-bulk transport begins at ∼700 K provided that the initial oxide loading exceeds 0.68 ML. The system stabilises at ∼ 1400 K with formation of a tenaciously held residual oxide film which is shown by LEER, Auger, and XPS measurements to be an expanded monolayer of TiO. No surface → bulk transport occurs for TiO, loadings below the critical value of 0.68 ML. Chemisorptive properties have been studied as a function of HTT-TiOx, film coverage and the results are discussed with respect to the SMSI phenomenon. © 1991.