Photoluminescence of terbium-containing sol-gel glasses

Glasses of the following composition: T glass SiO₂, TL glass SiO₂/ligand, T-Tb glass SiO₂/terbium complex were obtained by the method of acid catalyzed hydrolytic homo- and cocondensation of tetraethoxysilane (the source of SiO₂) with 3-(3-triethoxysilylpropyl)pentane-2,4-dione (the ligand) and terbium(III) tris[3-3-triethoxysilylpropyl)pentane-2,4-dionate] (terbium complex). The study of the fluorescence spectra showed that the cationic luminescence is achieved by the excitation of terbium-containing glasses at the absorption band of the ligand (λ_exc 275–280 nm). Energy transfer from the matrix (SiO₂) to the ligand and cation with the following emission of Tb³⁺ is possible on exciting the T-Tb glass by the light with the wavelength 360 nm. However, this method of generating terbium cation emission seems to be less efficient.