Energy transfer from Bi3+ sensitizing the luminescence of Eu3+ in clusters embedded into sol–gel silica glasses

Y3+(La3+), Eu3+ and Bi3+ ions co-doped sol–gel silica glasses were synthesized. Photoluminescence spectra show that there is energy transfer from Bi3+ ions to the emission band of Eu3+ ions. The co-dopants Y3+ or La3+ have strong effects on the local structure and luminescence of Eu3+ ions. For 0.5 mol% Eu3+ ions doped glasses, the co-doping of 1 mol% Bi3+ and 1 mol% Y3+ is the most appropriate for the sensitization from Bi3+ to Eu3+. The sensitization effectiveness from Bi3+ ions to Eu3+ ions was studied by changing the amount of Bi3+ and Y3+, and clusters containing rare earth ions and Bi3+ ions dominate the energy transfer processes. The comparison of luminescent R-values (the intensity ratio of 5D0 → 7F2/5D0 → 7F1 in Eu3+ ions) between glasses containing La3+ and containing Y3+ verifies the formation of clusters in sol–gel glasses. As a favorable configuration for energy transfer, the accurate design and synthesis of clusters-contained glasses may provide a new kind of luminescent materials.