An XPS study on the surface reduction of V2O5(001) induced by Ar ion bombardment
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چکیده
The effect of the irradiation with Al Ka X-rays during an XPS measurement upon the surface vanadium oxidation state of a fresh in vacuum cleaved V2O5(001) crystal was examined. Afterwards, the surface reduction of the V2O5(001) surface under Ar + bombardment was studied. The degree of reduction of the vanadium oxide was determined by means of a combined analysis of the O1s and V2p photoelectron lines. Asymmetric line shapes were needed to fit the V2p photolines, due to the metallic character of V2O3 at ambient temperature. Under Ar bombardment, the V2O5(001) crystal surface reduces rather fast towards the V2O3 stoichiometry, after which a much slower reduction of the vanadium oxide occurs. 2006 Elsevier B.V. All rights reserved.
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