Integrated Experimental-Theoretical Approach To Determine Reliable Molecular Reaction Mechanisms on Transition-Metal Oxide Surfaces.

By combining experimental and theoretical approaches, we investigate the quantitative relationship between molecular desorption temperature and binding energy on d and f metal oxide surfaces. We demonstrate how temperature-programmed desorption can be used to quantitatively correlate the theoretical surface chemistry of metal oxides (via on-site Hubbard correction) to gas surface interactions for catalytic reactions. For this purpose, both CO and NO oxidation mechanisms are studied in a step-by-step reaction process for perovskite and mullite-type oxides, respectively.

Stable and Active Oxidation Catalysis by Cooperative Lattice Oxygen Redox on SmMnO Mullite Surface.

The correlation between lattice oxygen (O) binding energy and O oxidation activity imposes a fundamental limit in developing oxide catalysts, simultaneously meeting the stringent thermal stability and catalytic activity standards for complete oxidation reactions under harsh conditions. Typically, strong O binding indicates a stable surface structure, but low O oxidation activity, and . Using nitric oxide (NO) catalytic oxidation as a model reaction, we demonstrate that this conflicting correlation can be avoided by cooperative lattice oxygen redox on SmMnO mullite oxides, leading to stable and active oxide surface structures.

First principles study of the Mn-doping effect on the physical and chemical properties of mullite-family AlSiO.

Transition metal (TM) modification is a common strategy for converting an earth-abundant mineral into a cost-effective catalyst for industrial applications. Among a variety of minerals, AlSiO, which has three phases, andalusite, sillimanite and kyanite, is emerging as a promising candidate for new catalyst development. In this paper, we use Mn to demonstrate the rationale of 3d TM doping at the Al sites in each of these three phases through first-principles calculations and the cluster expansion method.