Vanadium oxides thin films grown on rutile TiO2(110)-(1×1) and (1×2) surfaces
نویسندگان
چکیده
Vanadium oxides on rutile TiO2(110)-(1×1) and (1×2) surfaces have been prepared under ultrahigh vacuum conditions by evaporation of vanadium in background O2 and characterized by various vacuum surface analytical techniques. Auger electron spectroscopy (AES), low-energy electron diffraction (LEED), high-resolution electron energy loss spectroscopy (HREELS) and X-ray photoelectron spectroscopy ( XPS) including core-level and X-rayinduced valence band, indicate the formation of 23 on both substrates at vanadia coverages greater than one monolayer equivalent (MLE). The dispersion of vanadia is higher on the (1×2) surface than on the (1×1) surface. At lower coverages <1 MLE, the interface shows two chemical states of vanadium, V3+ and V4+. © 1999 Elsevier Science B.V. All rights reserved.
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