aKey Laboratory of Material Science and Technology for High Power Lasers, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
bGraduate School of the Chinese Academy of Sciences, Beijing 100039, China
cState Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China
dState Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027, China
Received 20 September 2008;
Abstract
The luminescent properties of Eu3+-doped porous glass were investigated and reduction of Eu3+ to Eu2+ was observed when the Eu3+-doped porous glasses were heat treated in air. The absorption, emission and excitation spectra of Eu3+-doped porous glasses were measured and the results significantly depended on the treating temperature. The integral intensity of Eu3+ and Eu2+ ions at different temperatures was also investigated to investigate this reduction process. Electron spin resonance (ESR) spectra of the samples were also measured, which also confirmed the reduction effect. A possible mechanism was discussed to explain this process.