2, U.S. Army Research Office, Research Triangle Park, North Carolina, United States
An active catalyst for the oxidation of CO at all temperatures is essential to ensuring safer air quality. In this study, we demonstrate the use of light to enhance CO oxidation over Mg(OH)2 and MgO supported gold catalysts, resulting in high activity and more substantial lifetimes at all temperatures ranging from -50 to 250 °C. Catalysts are synthesized by impregnation with plasmonic gold nanoparticles with a known size and plasmon resonance frequency. Using experiments which couple light induced desorption of CO2 and regeneration of catalytic activity, we propose a mechanism for light enhancement of gold catalysis. Light reactivates gold catalysts by removing surface carbonates which otherwise form in the active sites and poison the catalyst. This more efficient application allows for dramatically increased catalytic activity and catalyst lifetime, demonstrating a new path for highly active CO oxidation.