Implications of Pr3+ ions on structural, opto-thermal features of alkali zinc boro-tellurite glass systems for optical and laser technology applications

A novel multicomponent series of Pr3+ -ions doped borotellurite glasses with composition (45-y)B2O3+20TeO2+20ZnO+5Pb3O4+10Na2O+yPr6O11, where y = 0.0, 0.3, 0.6, 1.0, 1.5, and 2 mol%, were prepared. By the XRD technique, the non-crystalline state of the prepared glasses was validated. ATR-FTIR and Raman spectroscopy confirmed the presence of functional units, including BO4, BO3, TeO4, TeO3, and Pb–O and Zn–O links. The thermal analysis by DSC shows that glass transition and crystallization temperatures are found between 409 $${\rm ^\circ C}$$ and 461 $${\rm ^\circ C}$$, and 511 $${\rm ^\circ C}$$ and 572 $${\rm ^\circ C}$$. UV-visible absorption spectroscopy characterization reveals the transitions 3H4 → 3P2, 3P1, 3P0, and 1D2 corresponding to wavelengths of 444 nm, 470 nm, 483 nm, and 590 nm. The emission spectra of Pr3+ ions embedded in glass samples were recorded by a spectrofluorometer with an excitation wavelength of 444 nm. Among the observed transitions, the 3P0 → 3H4 (488 nm) and 3P1 → 3H5 (605 nm) transitions exhibited the most intense peaks. The CCT value of orange emission is found to be < 4000 K, implying warm CCT, whereas blue emission is > 4000 K, implying cool CCT. The optical and physical parameters were evaluated with appropriate formulae. The density and refractive index range from 3.710 gcm− 3 to 4.112 gcm− 3 and 2.356 to 2.368, respectively. The energy band gap varies from 3.154 eV to 3.110 eV. Metallization criterion and the electronic oxide polarizability vary in the range from 0.397 to 0.394 and 4.243 Å to 4.376 Å, respectively. By considering their structural, thermal, optical, and luminescence properties, the prepared glasses are promising materials for optical technologies, including LEDs and lasers.