Chinese Acad Sci, Inst Coal Chem, State Key Lab Coal Convers, Taiyuan 030001, Peoples R China
; Chinese Acad Sci, Inst High Energy Phys, Beijing 100039, Peoples R China
Small angle X-ray scattering (SAXS) with synchrotron radiation as X-ray source has been used to study the structure of silica xerogels prepared by sol-gel process. Both the agreement of SAXS profiles with and the deviation from Pored's law and Debye's theory have been found, showing that there are differences between the structures of these xerogels. The specific surfaces of the samples whose SAXS profiles agreed with Pored's law and Debye's theory have been determined by analyzing SAXS data according to the methods of Porod and Debye, respectively, and the results of both methods used were found to be similar. We have proposed the corresponding Pored and Debye analysis methods to determine the specific surfaces of samples whose SAXS profiles do not agree with Pored's law and Debye's theory, i.e. the negative or positive deviation. The results of both methods used here were also found to be close to each other. The specific surfaces fell between approximately 80-150 m(2)/cm(3) for the samples prepared under various conditions.