文摘
In water-promoted CO oxidation, water was thought not to directly participate in CO<sub>2sub> production. Here we report that via a water-mediated Mars–van Krevelen (MvK) mechanism, water can directly contribute to about 50% of CO<sub>2sub> production on a single-atom Pt<sub>1sub>/CeO<sub>2sub> catalyst. The origin is the facile reaction of CO with the hydroxyl from dissociated water to yield the carboxyl intermediate, which dehydrogenates subsequently with the help of a lattice hydroxyl to generate CO<sub>2sub> and water. The water-mediated MvK type reaction found here provides new insights in the promotion role of water in heterogeneous catalysis.