Short-range order of titania doped silica sono-aerogel

Abstract The atomic arrangements around Ti atoms in titania doped silica gels were studied by X-ray absorption spectroscopy. The gels were prepared by ultrasonic treatment of an alkoxide and acidic water mixture (sonogel) and conventionally in alcoholic solution. From the comparison of gels, XANES spectra with those of SrTiO 3 , anatase and rutile TiO 2 , an octahedral environment of Ti in the SiO 2 network can be inferred. These octahedra are distorted as in the case of TiO 2 . Ti did not occupy the Si sites but rather accumulated in domains where the Ti atoms are especially abundant. The sonogel network is formed up to the second neighbor level, contrary to the classic gel in which no coordination spheres can be made out above the first neighbor sphere.