Investigation of self-assembled fractal porous-silica over a wide range of length scales using a combined small-angle scattering method

Yamaguchi, Daisuke; Mayama, Hiroyuki*; Koizumi, Satoshi; Tsujii, Kaoru*; Hashimoto, Takeji

The fractal dimensions of specific porous silica materials were investigated by a wide-q observation using ultra-small-angle neutron scattering technique. In order to control the fractal dimension of porous silica material, flaky particles made of alkylletene dimer (AKD) were employed as moulds and silica matrix was formed by sol-gel process. After the solidification of the silica matrix, the original AKD moulds were completely burnt away at high temperature (ca. 930K) and became pores having a particular fractal dimension. The fractal dimension of the pores was changeable by the compression of the AKD mould at different ratio during the sample preparation. We found that the fractal structure obtained in this study was distinctly different from those of ordinary silica aerogels.