Abstract
Extended x-ray-absorption fine structure and scanning electron microscopy have been applied to the structure of the vanadium oxide layers on impregnated and grafted vanadium aerosils. When aerosil is impregnated with NH4VO3 solution, V2O5 crystals are formed; when vanadium is grafted by reacting the oxychloride with carrier OH groups, there are no visible crystals. On the other hand, the EXAFS spectra for the grafted specimens show all the oscillations found for crystalline V2O5. It is concluded that the vanadium oxide layers in these grafted materials have a long-range order similar to that in V2O5 and contain microcrystals having sizes up to 5 nm.
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Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 23, No. 5, pp. 652–655, September–October, 1987.
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Zazhigalov, V.A., Belousov, V.M., Kozlovski, R. et al. Exafs and electron-microscopy studies on V/SiO2 catalysts. Theor Exp Chem 23, 601–604 (1987). https://doi.org/10.1007/BF01128465
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DOI: https://doi.org/10.1007/BF01128465