Recent research progress in the study of catalytic CO oxidation by gas phase atomic clusters

Oxidation of CO into CO 2 is a major solution to reduce CO emission into the atmosphere and to remove CO in fuel gas cleanup. Furthermore, CO oxidation serves as a prototypical reaction for heterogeneous catalysis. This review provides an overview and an update on how to study catalytic CO oxidation at a strictly molecular level by performing well-controlled gas-phase experiments in combination with quantum chemistry calculations. The advances in the unique catalytic reactivity of single-atom cluster catalysts are emphasized. The catalytically active sites and various mechanistic aspects in the redox couples N 2 O/CO and O 2 /CO for the seemingly simple oxidation reaction are described.