Electron-Mediated CO Oxidation on the TiO₂(110) Surface during Electronic Excitation

Abstract

The role of electrons and holes in the electronically excited oxidation of adsorbed CO on TiO(2)(110) has been investigated by tuning the surface electron and hole availability by the adsorption of Cl(2) or O(2). The presence of an electron acceptor (Cl(2) or O(2)) on the TiO(2)(110) surface causes upward band bending, increasing the excited hole availability and decreasing the excited electron availability in the near surface region. This enhances O(2) desorption and depresses CO(2) production during electronic excitation. This result gives clear evidence for the first time that the electronically excited CO oxidation reaction is caused by an electron-mediated process in contrast to O(2) desorption which is mediated by holes.

Role of Hot Electrons and Metal–Oxide Interfaces in Surface Chemistry and Catalytic Reactions

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Adsorption, Activation, and Dissociation of Oxygen on Doped Oxides

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Highly n-Type Titanium Oxide as an Electronically Active Support for Platinum in the Catalytic Oxidation of Carbon Monoxide

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