Rh₁/γ‐Al₂O₃ Single‐Atom Catalysis of O₂ Activation and CO Oxidation: Mechanism, Effects of Hydration, Oxidation State, and Cluster Size

The single‐atom catalysis of O 2 activation and CO oxidation with Rh 1 supported on γ‐Al 2 O 3 is investigated here through ab initio molecular dynamics techniques. We scrutinize the molecular details of the mechanism for the full catalytic cycle that involves the oxidation of two CO molecules in succession. The effect of the surface hydration and oxidation state of Rh on the kinetics of O 2 activation and CO oxidation is presented. We also report here the catalytic activity of experimentally intercepted Rh I (CO) 2 on γ‐Al 2 O 3 . Furthermore, we delineate the importance of single‐atom catalysis by comparing the performance of the Rh 6 /Al 2 O 3 catalyst. A molecular level understanding of the differential reactivity on hydration, on oxidation, and of a larger Rh cluster size is reported.