Increase in the Tb3+ green emission in SiO2-LaF3 nano-glass-ceramics by codoping with Dy3+ ions

95SiO(2)-5LaF(3) sol-gel derived nano-glass-ceramics single doped with 0.1Dy(3+) or 0.1Tb(3+) mol % and codoped with 0.1Dy(3+) and xTb3+ (x = 0.1, 0.3) mol % were successfully obtained. XRD and HRTEM measurements confirm the precipitation of LaF3 nanocrystals during the ceramming process, with mean size ranging from 10 to 20 nm and increasing with the thermal treatment temperature. About 75% of lanthanide ions are partitioned into LaF(3)s nanocrystals, as calculated from luminescence decays. The effect of increasing the Tb3+ concentration and also of codoping with Dy3+ in the Tb3+ green emission from the D-5(4) level have been studied. The energy transfer mechanisms between Tb3+ ions and also between Tb3+-Dy3+ ions, which favor the green emission, have been analyzed. (c) 2010 American Institute of Physics. [doi: 10.1063/1.3514552]