CO Oxidation Promoted by Gold Atoms Loosely Attached in AuFeO₃^– Cluster Anions

Time-of-flight mass spectrometry experiment shows that upon the interactions with carbon monoxide, the mass-selected AuFeO₃^– oxide cluster anions can evaporate neutral gold atoms in a hexapole collision cell and oxidize CO into CO₂ in an ion trap reactor. The computational studies identify that the gold atom is loosely attached in the AuFeO₃^– cluster, and the different reaction channels can be attributed to different cluster velocities. The structure of the AuFeO₃^– cluster is very flexible, and the approach of CO induces significant geometrical and electronic structure changes of AuFeO₃^–, which facilitates the exposure of the positively charged gold atom to trap and oxidize CO. The CO oxidation by the AuFeO₃^– cluster follows the Au-assisted Mars–van Krevelen mechanism, in which the direct participation of the surface lattice oxygen (O^2–) is proposed.