Energy transfer between L-centres and Eu3+ ions in PbO-Na2O-SiO2 glasses doped with Eu2O3

PbO-Na2O-SiO2 glasses having SiO2 to Na2O mole ratio 3 and doped with 0.25 and 1.0 wt% Eu2O3 were prepared by melt-quench method. Both doped and un-doped glasses were characterized by strong emission in the visible region around 410 nm characteristic of the modified L-centre present in the glass. On doping the glasses with Eu3+ ions, the lifetime value of the L-centre emission has been found to decrease significantly and this has been attributed to the energy transfer taking place from the excited state of L-centre to the Eu3+ energy levels. Above 0.25 wt% Eu2O3 incorporation, there exists significant quenching among the Eu3+ ions as revealed by the poor luminescence characteristic of the sample. (author)