Influence of alumina on emission characteristics of Gd³⁺ ions in lead silicate glasses

In this study, we synthesized lead aluminosilicate glasses doped with Gd³⁺ ions and investigated the effects of varying Al₂O₃ concentrations on their properties. Specifically, we explored the photoluminescence behavior as well as the optical, infrared, and other spectroscopic characteristics of these glasses. Our infrared (IR) spectroscopic analysis revealed that the depolymerization of the glass network progressively increased with Al₂O₃ concentrations up to 5.0 mol%. Under excitation at 273 nm, corresponding to the ⁶P_7/2→⁸S_7/2 transition of Gd³⁺ ions, we observed significant UVB emissions at 311 nm. Notably, the emission intensity of glass containing 5.0 mol% Al₂O₃, when mixed with alumina-free glass, was found to be four times greater than that of glass with 1 mol% alumina. This enhancement in emission can be attributed to the declustering of Gd³⁺ ions and the ability of Al³⁺ ions to reduce cross-relaxation losses, thus enriching the photoluminescence properties. These findings provide valuable insights into the design and optimization of lead aluminosilicate glasses for applications requiring enhanced UVB emissions.