Ferrocene-Modified Siloxane Aerogels

Abstract

An efficient method has been developed for the synthesis of siloxane aerogels with a hybrid structure built into the polymer structure. At the initial stage, a gel was obtained by polycondensation of tetraethoxysilane and ferrocene-containing alkoxysilanes, catalyzed by BF₃ ⋅ Et₂O in acetone. The transformation of gels into aerogels was performed using supercritical carbon dioxide (SC-CO₂). The aerogel samples were characterized in detail by Mössbauer spectroscopy and nitrogen adsorption methods, and the density of the materials was determined. The iron content in the resulting aerogels varied from 3.6 to 8.7 wt % (or 11.9–28.7 wt % ferrocene units).