Reduction of Eu 3+ to Eu 2+ in Aluminoborosilicate Glasses Prepared in Air

Eu 2 O 3 ‐doped aluminoborosilicate glasses were prepared in air at high temperature. Luminescence measurements were used to investigate a valence change from Eu 3+ to Eu 2+ ions in the aluminoborosilicate glasses. The results showed that the doped Eu 3+ ions were partially reduced to Eu 2+ in the Eu 2 O 3 :RO–Al 2 O 3 –B 2 O 3 –SiO 2 (RO=CaO, SrO, BaO, Li 2 O) glasses, but not in the Eu 2 O 3 :RO–Al 2 O 3 –B 2 O 3 –SiO 2 (RO=Na 2 O, K 2 O) glasses. The changes of Eu reduction with different RO components were discussed with the variation of optical basicity of RO and with different valency of R cations. The effects of co‐doping BaO and ZnO in aluminoborosilicate glasses on Eu reduction were also investigated and discussed.