| Research on the effect of preparation technology of in-situ synthesis to microstructure of gel and the hydrolysis and polymerization of tetraethyl orthosilicate (TEOS), formation, structure and control methods of SiO2 gel by using BET and IR methods were reviewed in this paper. Research on the effect of ratio of hydrolysis and polymerization to distribution of polymerization manner,distribution of grain of gel and structure of gel, the optimum processing parameters were determined, mol ratio n(H2O): n(TEOS): n(C2H5OH) =4: 4: 1 and pH=2～3, by which SiO2 can be prepared with exhibited a quadrilateral arrangement of uniform structure. It can meet preparing structure controllable inorganic materials with the features of good performance, short periodic.This paper investigated the structures, spectral characters and luminescence behaviors of the Tb complexes by in - situ synthesis method. It was found that the narrow excitation spectra of terbium were replaced by the broad excitation spectra of their corresponding complexes in gel glass and that the intensity of the emission spectra of these gel glass varied with the concentration of lanthanide ion, ligands, heat-treatment time and temperature while the wavelength of the emission peak remain unchanged, which indicated the in-situ synthesis of the terbium complexes.The effect of the doping concentration of the lanthanide ions and ligands as well as the heat-treatment time on the luminescence behavior of the lanthanide ions codoped gel glass was systematically studied. The results showed that the emission intensity of rare earth complexes and the amount of the in situ synthesized rare earth complexes in the gel glass increased with the increase of the heat-treatment time. The fluorescence spectra of these materials presented a series of narrow lines assigned to the transitions of Tb3+. The high emission intensity observed was a promising property for application in technological luminescent devices.
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