Reactivity of monolayer V2O5 films on TiO2(110) produced via the oxidation of vapor-deposited vanadium
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چکیده
The growth, and reactivity of monolayer V2O5 films supported on TiO2(110) produced via the oxidation of vapor-deposited vanadium were studied using X-ray photoelectron spectroscopy (XPS) and temperature programmed desorption (TPD). Oxidation of vapor-deposited vanadium in 10-7 Torr of O2 at 600 K produced vanadia films that contained primarily V+3, while oxidation in 10-3 Torr at 400 K produced films that contained primarily V+5. The reactivity of the supported vanadia layers for the oxidation of methanol to formaldehyde was studied using TPD. The activity for this reaction was found to be a function of the oxidation state of the vanadium cations in the film. Comments Postprint version. Published in Surface Science, Volume 526, Issue 3, 1 March 2003, pages 211-218. Publisher URL: http://dx.doi.org/10.1016/S0039-6028(03)00006-2 This journal article is available at ScholarlyCommons: http://repository.upenn.edu/cbe_papers/7 1 Reactivity of Monolayer V2O5 Films on TiO2(110) Produced via the Oxidation of Vapor-Deposited Vanadium G.S. Wong, M.R. Concepcion and J.M. Vohs Department of Chemical Engineering University of Pennsylvania Philadelphia, PA 19104-6393 Abstract The growth, and reactivity of monolayer V2O5 films supported on TiO2(110) produced via the oxidation of vapor-deposited vanadium were studied using X-ray photoelectron spectroscopy (XPS) and temperature programmed desorption (TPD). Oxidation of vapor-deposited vanadium in 10 Torr of O2 at 600 K produced vanadia films that contained primarily V, while oxidation in 10 Torr at 400 K produced films that contained primarily V. The reactivity of the supported vanadia layers for the oxidation of methanol to formaldehyde was studied using TPD. The activity for this reaction was found to be a function of the oxidation state of the vanadium cations in theThe growth, and reactivity of monolayer V2O5 films supported on TiO2(110) produced via the oxidation of vapor-deposited vanadium were studied using X-ray photoelectron spectroscopy (XPS) and temperature programmed desorption (TPD). Oxidation of vapor-deposited vanadium in 10 Torr of O2 at 600 K produced vanadia films that contained primarily V, while oxidation in 10 Torr at 400 K produced films that contained primarily V. The reactivity of the supported vanadia layers for the oxidation of methanol to formaldehyde was studied using TPD. The activity for this reaction was found to be a function of the oxidation state of the vanadium cations in the
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