Processing of sol–gel silica using gamma radiation

The aAect of gamma radiation on the structure of silica gels obtained using tetramethoxysilane (TMOS) as chemical precursor and molar ratios TMOS:H2O varying from 1:4 up to 1:32 was studied. The structure of the silica gels produced was determined by X-ray diAraction and nitrogen gas sorption. The samples were irradiated with 60 Co c-rays to doses of 200 Gy. The xerogels obtained under gamma radiation had larger specific surface area and pore volumes than the gels obtained using a conventional sol‐gel process. The observed variation in those quantities was 2‐100 times larger. Gamma radiation promotes an overall stabilization of the polymerization process, resulting in more reproducible structures. ” 2000 Elsevier Science B.V. All rights reserved.