Regulating the Spatial Distribution of Ru Nanoparticles on CeO₂ Support for Enhanced Propane Oxidation

Developing efficient catalysts for the total oxidation of propane at low temperatures is challenging; however, it is crucial for the purification of automotive exhaust and volatile organic compounds emitted in industrial processes. We report a highly stable and active Ru-based catalyst for propane oxidation by tuning Ru loading to achieve the balance between RuOx species in the CeO2 bulk and on the surface via a facile coprecipitation approach (Ru–CeO2). Compared to the Ru catalyst prepared through wet impregnation on a CeO2 support (Ru/CeO2), the prepared Ru–CeO2 catalyst allows for the formation of RuOx species with smaller particle sizes and lower oxidation states, as well as an increased number of oxygen vacancies on the catalyst surface, leading to a greater ability to adsorb and activate propane and oxygen. As a result, the Ru–CeO2 catalyst presents a substantially improved activity and durability toward propane oxidation, which can maintain 90% propane conversion at 220 °C for 50 h. This work highlights the synthetic tuning of the spatial distribution of Ru active sites within catalysts through a coprecipitation strategy for improved catalytic alkane oxidation, and the prepared Ru–CeO2 catalyst is a promising candidate material for industrial applications.