RESUMO
As carbon monoxide oxidation is widely used for various chemical processes (such as methanol synthesis and water-gas shift reactions H2O + CO â CO2 + H2) as well as in industry, it is essential to develop highly energy efficient, inexpensive, and eco-friendly catalysts for CO oxidation. Here we report green synthesis of â¼10 nm sized CuO nanoparticles (NPs) aggregated on â¼400 nm sized 50-facet Cu2O polyhedral nanocrystals. This CuO-NPs/50-facet Cu2O shows remarkable CO oxidation reactivity with very high specific CO oxidation activity (4.5 µmolCO m-2 s-1 at 130 °C) and near-complete 99.5% CO conversion efficiency at â¼175 °C. This outstanding catalytic performance by CuO NPs over the pristine multifaceted Cu2O nanocrystals is attributed to the surface oxygen defects present in CuO NPs which facilitate binding of CO and O2 on their surfaces. This new material opens up new possibilities of replacing the usage of expensive CO oxidation materials.