A. M. Venezia, V. La Parola
The effect of the addition of alkali ions to commercial amorphous silica, commonly used as a support for heterogeneous catalysts, was investigated regarding morphological and structural changes. Alkali-doped silica samples were prepared through impregnation followed by calcination at various temperatures. The structural effects of lithium, sodium, potassium, and cesium were assessed using wide-angle X-ray scattering (WAXS) and small-angle X-ray scattering (SAXS) techniques. WAXS diffraction patterns were analyzed with the Rietveld method via the GSAS program, enabling the qualitative and quantitative identification of the different silica polymorph fractions such as quartz, tridymite, and cristobalite. SAXS measurements, employing classical methods based on Porod's law, yielded the overall surface area of the systems, which were compared with those determined using the nitrogen adsorption technique and the Brunauer-Emmett-Teller method. The findings are elucidated in the context of the sizes of the alkali ions and the cell volume of the distinct crystalline phases.
@article{5a3f9a99-8abb-4f2a-aca0-6e6697a15766,
title={Effect of Alkali Ions on the Amorphous t},
author={A. M. Venezia and V. La Parola},
year={2026},
language={en}
}TY - JOUR TI - Effect of Alkali Ions on the Amorphous t AU - A. M. Venezia AU - V. La Parola PY - 2026 LA - en ER -
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