Complete CO Oxidation over Cu2O Nanoparticles Supported on Silica Gel

Abstract

We find that nearly monodisperse copper oxide nanoparticles prepared via the thermal decomposition of a Cu(I) precursor exhibit exceptional activity toward CO oxidation in CO/O2/N2 mixtures. Greater than 99.5 % conversion of CO to CO2 could be achieved at temperatures less than 250 °C for over 12 h. In addition, the phase diagram and pathway for CO oxidation on Cu2O (100) is computed by ab initio methods and found to be in qualitative agreement with the experimental findings. Nanoparticles offer a larger surface-to-volume ratio and a higher concentration of partially coordinated surface sites than the corresponding bulk materials. The unique properties of nanoparticles are due to a strong interplay between elastic, geometric, and electronic parameters, as well as the effects of interactions with the support. The result of these features is often improved physical and chemical properties compared to the bulk material. It is for these reasons that heterogeneous catalysis at nanoparticle surfaces is currently under intense investigation in the catalysis community at large.1,2 Con