Solvothermal removal of the organic template from L-3 ("sponge") templated silica monoliths

Citation:

Dabbs, D. M. ; Mulders, N. ; Aksay, I. A. Solvothermal removal of the organic template from L-3 ("sponge") templated silica monoliths. Journal of Nanoparticle Research 2006, 8 603-614.

Date Published:

Oct

Type of Article:

Article

ISBN Number:

1388-0764

Accession Number:

WOS:000241949000007

Abstract:

We compare the methods of continuous solvent (Soxhlet) and supercritical solvent extractions for the removal of the organic template from nanostructured silica monoliths. Our monoliths are formed by templating the L-3 liquid crystal phase of cetylpyridinium chloride in aqueous solutions with tetramethoxy silane. The monoliths that result from both Soxhlet and supercritical extraction methods are mechanically robust, optically clear, and free of cracks. The Soxhlet method compares favorably with supercritical solvent extraction in that equivalent L-3-templated silica can be synthesized without the use of specialized reactor hardware or higher temperatures and high pressures, while avoiding noxious byproducts. The comparative effectiveness of various solvents in the Soxhlet process is related to the Hildebrand solubility parameter, determined by the effective surface area of the extracted silica.