• Bulletin of the Korean Chemical Society
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• v.24 no.3
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• pp.311-317
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• 2003

Vanadium oxides supported on zirconia and modified with MoO₃were prepared by adding Zr(OH)₄powder into a mixed aqueous solution of ammonium metavanadate and ammonium molybdate followed by drying and calcining at high temperatures. The characterization of prepared catalysts was performed using FTIR, Raman spectroscopy and solid-state $^{51}V$ NMR. In the case of a calcination temperature of 773 K, for samples containing low loading of $V_2O_5$, below 15 wt %, vanadium oxide was in a highly dispersed state, while for samples containing high loading of $V_2O_5$, equal to or above 15 wt %, vanadium oxide was well crystallized because the $V_2O_5$ loading exceeded the formation of a monolayer on the surface of $ZrO_2$. The $ZrV_2O_7$ compound was formed through the reaction of $V_2O_5\;and\;ZrO_2$ at 873 K and the compound decomposed into $V_2O_5\;and\;ZrO_2$ at 1073 K, which were confirmed by FTIR spectroscopy and solid-state $^{51}V$ NMR. IR spectroscopic studies of ammonia adsorbed on $V_2O_5-MoO_3/ZrO_2$ showed the presence of both Lewis and Bronsted acids.

• Journal of the Korean Magnetic Resonance Society
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• v.4 no.1
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• pp.1-11
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• 2000

Supported vanadium oxides are being used extensively as catalysts for a variety of reactions, including partial oxidations and ammoxidations. A series of vanadium oxide supported on TiO2-ZrO2 was obtained by impregnating ammonium metavanadate slowly into a mixed precipitateof Ti(OH)4-Zr(OH)4, followed by calcining in air at high temperatures. The prepared catalysts were characterized by 51V solid-state NMR. In the calcined catalysts 51V NMR studies indicated the peaks corresponding to distorted tetrahedral vanadia species at low V2O5 contents and octahedral vanadia species at high vanadia loadings. These results illustrate the suitability of 51V NMR as a unique quantitative spectroscopic tool in the structural analysis of vanadium(V) oxide catalytic materials.

• Applied Chemistry for Engineering
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• v.21 no.2
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• pp.211-216
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• 2010

$(NH_4)_{0.3}V_2O_5$ nanorods and $V_2O_5$ nanosheets have been synthesized by the reaction of $V_2O_5$ gel via homogeneous precipitation process employing urea and formic acid. The electrochemical and chemical characteristics of these nanomaterials have been investigated using TGA, SEM, FT-IR, XRD, and LSV. The interlayer distance of $(NH_4)_{0.3}V_2O_5$ was about $10.7{\AA}$, and that of $V_2O_5$ synthesized by using formic acid was $14.2{\AA}$. The surface morphology of $(NH_4)_{0.3}V_2O_5$ and $V_2O_5$ showed features that looked like nanorods and nanosheets, respectively. Specific capacity of $(NH_4)_{0.3}V_2O_5$ nanorods prepared at $95^{\circ}C$ was at least 280 mAh/g at 10 mA/g discharge rate.