Doping Effects on the Reactivity of the MVO5– (M = V–Zn) Clusters in CO Oxidation Reaction

Abstract

Doped metal oxide catalysts have important applications in heterogeneous catalysis, whereas the fundamental effects of doping on the reactivity of catalysts are elusive. Herein, benefiting from the study of a series of atomic clusters MVO5– (M = V–Zn) in catalytic CO oxidation by molecular O2 under thermal collision conditions, the crucial effects of doping on the electronic structure and then the catalytic reactivity of MVO5– were successfully rationalized by using mass spectrometry and theoretical calculations. We defined the energy gap of active orbitals that are closely related to electron transfer in MVO5– during CO oxidation. It was discovered that such an energy gap can modulate reaction thermodynamics, whereas the orbital overlap of MVO5– with CO controls the kinetics. The doped clusters MVO5– (M = Cr–Zn) have reduced energy gaps than that in host V2O5–, and doping can modify the orbital overlap of MVO5– (M = Cr–Zn) with CO. Only the MnVO5– and ZnVO5– clusters that have rational energy gaps and pr...