Experimental and Theoretical Characterization of Superoxide Complexes [W2O6(O2−)] and [W3O9(O2−)]: Models for the Interaction of O2 with Reduced W Sites on Tungsten Oxide Surfaces

Photoelectron spectroscopic analysis and DFT calculations of two O-rich tungsten oxide clusters [W2O8]− and [W3O11]− showed these anions are superoxide complexes [W2O6(O2−)] and [W3O9(O2−)]. The data suggest that the clusters [W2O6]− and [W3O9]− can activate O2 through a one-electron transfer to form superoxide, which makes them simple molecular models for the chemisorption of O2 at reduced defect sites on tungsten oxide surfaces.