Study of growth and oxidation of vanadium films on α-Fe2O3(0001)
نویسندگان
چکیده
Electronic structures of the vanadium/vanadium-oxide films supported on α-Fe2O3(0001) were studied by using X-ray photoemission spectroscopy. The vanadium films were grown by evaporation of metallic vanadium at room temperature. The as-deposited V had a 3+ oxidation state and the α-Fe2O3(0001) surface was reduced at the initial coverage. After complete reduction of interface iron atoms, metallic V started to grow at a vanadium coverage greater than 2/3 monolayer. The V2O5 film was prepared by exposing the pre-deposited vanadium film to the atomic oxygen at room temperature. Converting to the V2O5 film was accompanied by re-oxidation of the α-Fe2O3 at the interface. The reduction and reoxidation of interfacial iron manifest electron transfer between the adsorbed vanadium and substrate. © 2006 Elsevier B.V. All rights reserved.
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