Multifunctional Gd³⁺- doped tellurite glass for photonic, radiation shielding, and dosimetric applications

A novel Gd³⁺-activated tellurite glass with the composition 65TeO₂-15MgO-9SrO-5ZnO-5Ta₂O₅-1Gd₂O₃ (TeMgSrTa³⁺) was developed through the conventional melt-quenching route to investigate its combined optical, luminescent, electron paramagnetic resonance, thermoluminescence, and radiation shielding characteristics within a single glass matrix. The novelty of this work lies in the incorporation of Ta₂O₅ and Gd³⁺ into the TeO₂-MgO-SrO-ZnO glass network, enabling the simultaneous realization of ultraviolet photoluminescence, favorable dosimetric response, and efficient photon and neutron attenuation, which has not been comprehensively reported for this glass composition. X-ray diffraction confirmed the formation of a completely amorphous structure, while FTIR analysis identified TeO₄ and TeO₃ structural units responsible for network modification. UV-Visible spectroscopy revealed excellent optical transparency, and the characteristic absorption bands observed at 209, 247, and 347 nm were assigned to the 4f-5d transitions of Gd³⁺ ions. Under ultraviolet excitation, the glass exhibited a strong emission centered at 313 nm, originating from the ⁶P₇/₂→⁸S₇/₂ transition of Gd³⁺, with chromaticity coordinates of x = 0.1487 and y = 0.0468, demonstrating its suitability for ultraviolet photonic applications. Comprehensive gamma-ray shielding analysis showed close agreement between experimental and theoretical attenuation parameters, including the mass attenuation coefficient, linear attenuation coefficient, half-value layer, tenth-value layer, and mean free path across a broad photon energy range. The measured fast neutron effective removal cross-section further confirmed the material's capability for neutron shielding. Thermoluminescence investigations produced well-defined glow peaks with favorable kinetic parameters, indicating promising dosimetric performance. Electron paramagnetic resonance analysis verified the valence state and local coordination environment of Gd³⁺ ions, providing insight into the ligand field surrounding the activator. The synergistic combination of structural stability, ultraviolet luminescence, radiation attenuation efficiency, and dosimetric response demonstrates that the proposed TeMgSrTa³⁺ glass is a promising multifunctional material for advanced photonic devices, radiation protection systems, and radiation sensing technologies.