Low-Density Silica Aerogels Observed by High-Resolution Electron Microscopy
- 15 August 1988
- journal article
- Published by IOP Publishing in Europhysics Letters
- Vol. 6 (8), 731-737
- https://doi.org/10.1209/0295-5075/6/8/011
Abstract
High-resolution electron microscope observations of two types of silica aerogels (base catalyzed and neutrally prepared) have shown two types of structures. The base catalyzed has an open structure with a 3D network of branched chains containing for very low density (0.03 g cm-3) two separate hierarchy levels. In neutrally or acid catalyzed aerogels self-similarity over two orders of magnitude is evidenced with a tendency to form several hierarchy levels in the lowest-density case (0.12 g cm-3). These results are in accordance with the range of fractal domains determined by small-angle neutron scattering.Keywords
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