Study of the valence state and coordination of antimony in MoVSbO catalysts determined by XANES and EXAFS

Millet, J.M.M.; Baca, M.; Pigamo, A.; Vitry, Damien; Ueda, Wataru; Dubois, Jean‐Luc

doi:10.1016/s0926-860x(02)00614-2

Cited by 84 publications

(58 citation statements)

References 16 publications

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“…Then the peak about 4707 eV, observed for Sb-doped film indicates an oxidation state of Sb 5+ . 8 XANES data obtained for thin films evidence the donor nature of Sb 5+ , which rules out hypothesis (ii). Results of reflection in the near infrared 9 show that Drude's theory applies, which means a carrier concentration is as high as 10 20 cm −3 .…”

Section: Results-discussionsupporting

confidence: 75%

EXAFS investigation on Sb incorporation effects to electrical transport in SnO2 thin films deposited by sol–gel

Geraldo

Briois

Scalvi

et al. 2007

Journal of the European Ceramic Society

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The effect of Sb doping in SnO 2 thin films prepared by the sol-gel dip-coating (SGDC) process is investigated. Electronic and structural properties are evaluated through synchrotron radiation measurements by EXAFS and XANES. These data indicate that antimony is in the oxidation state Sb 5+ and replaces tin atoms (Sn 4+ ), at a grain surface site. Although the substitution yields net free carrier concentration, the electrical conductivity is increased only slightly, because it is reduced by the high grain boundary scattering. The overall picture leads to a shortening of the grain boundary potential, where oxygen vacancies compensate for oxygen adsorbed species, decreasing the trapped charge at grain boundary.

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Section: Results-discussionsupporting

confidence: 75%

EXAFS investigation on Sb incorporation effects to electrical transport in SnO2 thin films deposited by sol–gel

Geraldo

Briois

Scalvi

et al. 2007

Journal of the European Ceramic Society

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“…We may speculate that these ions substitute Mo 5+ ions in pentagonal bipyramidal sites [9]. On the other hand, Millet [33] in this case, we cannot exclude an occupation of the channels. Adsorption data can be regarded as a confirmation of the above suppositions, since a lack of empty channels in the structure of the complex ternary oxide is indicated.…”

Section: Cross-linking By Mo-o-v Bridges Would Also Be In Agreement Withmentioning

confidence: 75%

The structural genesis of a complex (MoVW)5O14 oxide during thermal treatments and its redox behavior at elevated temperatures

Зенковец

Kryukova

Gavrilov

et al. 2007

Materials Chemistry and Physics

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The structural genesis of a Mo 0.68 V 0.23 W 0.09 oxide with Mo 5 O 14 -like structure has been examined.A precursor prepared by spray-drying of mixed aqueous metal salt solutions was calcined in air and subsequently treated in helium at different temperatures. X-ray diffraction, HRTEM, 51 V MAS NMR, ESR, UV/Vis DR spectroscopy and oxygen and hydrogen adsorption measurements have been applied to monitor the preparation procedure. It was found that a structure closely re-

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“…Mo-V-Te-Nb mixed metal oxide catalysts have been shown as the most promising materials for the (amm)oxidation of propane to acrylonitrile [1,2] [5], similar to those observed in Tecontaining solids. However, and although Sb-containing catalysts are active and selective in the (amm)oxidation of propane [6][7][8][9][10][11][12][13] and in the ODH of ethane [14], they generally present a selectivity to partial oxidation products lower than those obtained over the corresponding Te-containing catalyst [1-4, 13, [15][16][17][18].…”

Section: Introductionmentioning

confidence: 94%

Selective Oxidation of Propane Over AMoVSbO Catalysts (A = Li, Na, K, Rb or Cs)

et al. 2008

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Alkali metal-containing Mo-V-Sb-O catalysts (AMoVSbO, with A = Li, Na, K, Rb or Cs), prepared hydrothermally and activated at 600°C in N 2 , have been characterized and tested for the selective oxidation of propane. Alkali-doped catalysts resulted to be more selective to acrylic acid and less selective to acetic acid than the corresponding alkali-free Mo-V-Sb-O catalyst. However, the nature of crystalline phases and the catalytic behaviour strongly depend on the alkali metal added. In this way, the catalytic activity decreases as follows: unpromoted [ Li-* Na-* K-[ Rb-[ Cs-containing catalyst. However the selectivity to acrylic acid decreases in the order: K-[ Rb-* Na-[ unpromoted [ Li-[ Cscontaining catalyst. The role of the presence/absence of acid sites and cations on both the nature of crystalline phases and the catalytic performance will be discussed.

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Study of the valence state and coordination of antimony in MoVSbO catalysts determined by XANES and EXAFS

Cited by 84 publications

References 16 publications

EXAFS investigation on Sb incorporation effects to electrical transport in SnO2 thin films deposited by sol–gel

EXAFS investigation on Sb incorporation effects to electrical transport in SnO2 thin films deposited by sol–gel

The structural genesis of a complex (MoVW)5O14 oxide during thermal treatments and its redox behavior at elevated temperatures

Selective Oxidation of Propane Over AMoVSbO Catalysts (A = Li, Na, K, Rb or Cs)

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