Ru/CeO₂ Catalyst with Optimized CeO₂ Support Morphology and Surface Facets for Propane Combustion

Abstract

Tailoring the interfaces between active metal centers and supporting materials is an efficient strategy to obtain a superior catalyst for a certain reaction. Herein, an active interface between Ru and CeO₂ was identified and constructed by adjusting the morphology of CeO₂ support, such as rods (R), cubes (C), and octahedra (O), to optimize both the activity and the stability of Ru/CeO₂ catalyst for propane combustion. We found that the morphology of CeO₂ support does not significantly affect the chemical states of Ru species but controls the interaction between the Ru and CeO₂, leading to the tuning of oxygen vacancy in the CeO₂ surface around the Ru-CeO₂ interface. The Ru/CeO₂ catalyst possesses more oxygen vacancy when CeO₂-R with predominantly exposed CeO₂{110} surface facets is used, providing a higher ability to adsorb and activate oxygen and propane. As a result, the Ru/CeO₂-R catalyst exhibits higher catalytic activity and stability for propane combustion compared with the Ru/CeO₂-C and Ru/CeO₂-O catalysts. This work highlights a new strategy for the design of efficient metal/CeO₂ catalysts by engineering morphology and associated surface facet of CeO₂ support for the elimination of light alkane pollutants and other volatile organic compounds.