(387b) ALD-Overcoated Pt Catalyst for Oxidative Propane Dehydrogenation: Tandem Catalysts

Propane oxidative dehydrogenation can significantly increase poor equilibrium conversions of direct propane dehydrogenation through consuming produced hydrogen with oxidants, shifting propane dehydrogenation reaction to more catalytically-relevant reaction. Oxidants can be strong O2 molecule as well as soft CO2 molecule, determining selective oxidation reactions for hydrogen such as selective hydrogen combustion or reverse water gas shift reaction. To enable such tandem reaction, a catalyst has to be designed to have multiple reactive species, especially at molecular level. Herein, atomic layer deposition (ALD) was employed to control nanometer-scale conformal deposition of metal oxides. We deposited several metal oxides by ALD on Pt catalyst to build "overcoated" structure which is an inverse structure of general heterogeneous catalyst. The overcoated nanocatalysts offers not only multiple reactive species but also unique properties based on its overcoated structure. As a result, we characterized and tested ALD-derived metal oxide overcoats on Pt nanoparticle catalysts for oxidative propane dehydrogenation. Through the study, it was found that there were multiple cornerstones to enable tandem catalysis including proximity between active species, thermal stability, and reducibility, which will be described in this presentation.