Abstract: Tb3＋ ions were incorporated in SiO2 glasses using a solgel process with appropriate heat treatment.Glasses incorporated with Tb3＋ showed emission peaks at 488,544,585,and 620 nm,respectively,exhibiting,respectively,5D4—7FJ(J=3,4,5,6) transition of the Tb3＋ ions.The structural evolution during the transition from gel to glass of Tb3＋ doped SiO2 glasses and the effect on luminescence properties were studied by excitation spectra,emission spectra,IR,farIR and DTATG at differential heat treatment conditions.The results show that most of absorbed water molecules in gel were removed during heat treatment at 50～100 ℃,conversion from gel to glasses was the main structural changes when gel was heattreated in the range 150～500 ℃,and the luminescence intensity increased remarkably also,becoming stable structure at 800 ℃.This observation leads to a conclusion that the radiation electronic transitions of Tb3＋ were quenched strongly by O－H group and were enhanced by temperature elevation.

Key words: Sol-gel method, Tb-doped silica glasses, Luminescence properties