Textural characteristics of silica aerogels from SAXS experiments

doi:10.1016/0022-3093(90)90135-9

Journal of Non-Crystalline Solids

Volume 121, Issues 1–3, 1 May 1990, Pages 216-220

https://doi.org/10.1016/0022-3093(90)90135-9 Get rights and content

Abstract

Small angle X-ray scattering measurements on silica aerogels give systematically low values for the solid phase density. In order to explain these results, a hierarchical structure is proposed. Textural parameters such as specific surface area, size and density of clusters, and pore size are a function of the number of levels in the structure. Experimental values are consistent with values calculated for a hierarchy of two to four levels, depending on the initial sol concentration. The model can explain the fractal features for lower density aerogels.

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Textural characteristics of silica aerogels from SAXS experiments

Abstract

J. Non-Cryst. Solids

J. Non-Cryst. Solids

J. Non-Cryst. Solids

J. Chem. Phys.