De-quenching influence of aluminum ions on Y/B ratio of Dy3+ ions in lead silicate glass matrix

Emission features Dy3+ ion in lead alumino silicate glasses as a function of Al2O3 concentration were studied. The observed increase in the intensity of all these bands is found to increase with increase in the concentration of Al2O3 in the glass matrix and this increase is understood due to the decrease of luminescence quenching owing to declusterization of Dy3+ ions by Al3+ ions in the glass network. Photoluminescence spectra of Dy3+ doped PbO–Al2O3–SiO2 glasses recorded at room temperature in visible region excited at 451nm. •Emission features of Dy3+ ion were studied as a function of Al2O3 concentration in lead silicate glasses.•The emission spectra exhibited bands due to 4F9/2→6H15/2(B),6H13/2 (Y), 6H11/2 and 6H9/2 transitions.•The Y/B integral intensity ratio is found to decrease with increase in the concentration of Al2O3.•The decrease Y/B ratio is explained interms of structural modifications in the vicinity of the Dy3+ ion. Emission features of Dy3+ ions were characterized as a function of Al2O3 concentration in lead silicate glasses. The emission spectra exhibited conventional blue, yellow, orange and red emission bands due to 4F9/2→6H15/2, 6H13/2, 6H11/2 and 6H9/2 transitions of Dy3+ ions, respectively. The intensity of all these bands exhibited increasing trend with increase in the concentration of Al2O3 and this increase was attributed to decrease of luminescence quenching due to declusterization of Dy3+ ions by Al3+ ions in the glass network. From the emission spectra, the radiative parameters viz., spontaneous emission probability A, the total emission probability AT, the radiative lifetime τr, the fluorescent branching ratio β, of different transitions originated from 4F9/2 level of Dy3+ ions were evaluated. The Y(I4F9/2→6H11/2)/B(I4F9/2→6H15/2) integral emission intensity ratio of Dy3+ ions evaluated from the luminescence spectra, showed decreasing trend with increase in the concentration of Al2O3. The decrease of this ratio is explained basing on structural modifications taking place in the vicinity of the Dy3+ ion in the glass matrix. The CIE color coordinates for three glasses were evaluated and found to be in the yellow region.