Two anatase titania model catalysts, with preferential exposure of (101) and (001) facets, were synthized and studied for isopropanol dehydration and aldehyde C-C bond formation . A series of microscopic and spectroscopic techniques including XRD, SEM/TEM, NH3-TPD and chemical titration were employed to correlate the structure properties of the model catalysts to their catalytic performances. Based on selective site poisoning titration using 2,6-di-tert-butyl pyridine, surface Lewis acid sites were found to be active for isopropanol dehydration. The higher activity for TiO2 (101) catalyst was ascribed to its higher acid strength and density in comparison to TiO2 (001). Theoretical calculations using density functional theory assisted by kinetic isotope effect measurements further elucidated that dehydrated TiO2 (101) facet is more active than hydroxylated TiO2 (001) facet, and dehydration follows a concerted E2 elimination pathway on both facets with the β C-H bond cleavage governing the reaction rate. On the other hand, higher C-C bond formation activity on (001) facet is due to its stronger basicity.

Single-facet dominant anatase Titania model catalysts to elucidate the active sites for O elimination and C-C bond formation

2019 Spring National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.