Influence of Crystallization on the Luminescence Characteristics of Pr ³⁺ Ions in PbO–Sb ₂ O ₃ –B ₂ O ₃ Glass System

Abstract

PbO–Sb 2 O 3 –B 2 O 3 glasses mixed with different concentrations of Pr 2 O 3 (ranging from 0 to 0.6 mol%) were crystallized. The samples were characterized by X‐ray diffraction (XRD) and transmission electron microscopy techniques. The XRD studies have revealed the presence of Pb 5 Sb 2 O 8 , Pb 3 (SbO 4 ) 2 , PbB 4 O 7 , β‐PrSbO 4 , Pr 3 SbO 7 , and Pr 3 Sb 5 O 12 crystalline phases. Optical absorption (in the visible and NIR regions) and fluorescence spectra of these samples have been recorded at room temperature. The Judd–Ofelt theory could successfully be applied to characterize the absorption and luminescence spectra of Pr 3+ ions in these samples. From the luminescence spectra, various radiative properties like transition probability A , branching ratio β r , and the radiative lifetime τ r for various emission levels originating from the 3 P 0 level of Pr 3+ ion in the glasses glass ceramic samples have been evaluated. The radiative lifetime of the 3 P 0 → 3 H 6 transition is measured and the quantum efficiency has been estimated. The crystallization causes to improve the luminescence efficiency to a large extent. The changes observed in the radiative properties due to crystallization have been discussed in the light of varying co‐ordinations of antimony ions in the glass network.