Influence of Al3 + ions on luminescence efficiency of Eu3 + ions in barium boro-phosphate glasses

• Eu3 +: BaO–B2O3–P2O5 glasses mixed with variable concentration of Al2O3 were prepared
• Luminescence spectra of Eu3 + ions in the visible region is recorded.
• Enhancement in the quantum efficiency is observed due to increase of Al2O3 content.
• The increase is understood due to the declusterization of Eu3 + ions by Al3 + ions.

The emission and life time decay characteristics of Eu3 + ions in barium boro-phosphate glasses mixed with different concentrations of Al2O3 are studied. The emission spectra exhibited bands due to 5D0 → 7F0, 7F1, 7F2, 7F3, 7F4 transitions of Eu3 + ions. The highest intensity of these transitions is observed when the glasses are mixed with 3.0 mol% of Al2O3. Using the emission spectra, the Judd–Ofelt (J–O) parameters and the radiative parameters viz., emission probability, A, the radiative lifetime, τ, and the fluorescent branching ratio, β of different transitions originated from 5D0 level of Eu3 + ions are evaluated. The results have been analyzed as a function of Al2O3 concentration with the aid of IR spectral data. The IR spectral data have indicated that Al3 + ions participate in larger proportions in octahedral positions in the glasses mixed with 3.0 mol% of Al2O3, which induce bonding defects, de-cluster the Eu3 + ions and facilitate for minimizing the emission losses due to quenching. The quantitative analysis of these results further indicated that 3.0 mol% of Al2O3 is optimal for achieving the highest luminescence efficiency in these glasses.