Effect of cerium oxide on physical, structural, and spectroscopic properties of tellurium-borate glasses for cool greenish light emitting devices

This investigation is to explore how CeO₂ affects the physical, structural, and spectroscopic characteristics of tellurium soda-borate glasses for potential applications in optoelectronics. The conventional melt quenching technique was used to produce the necessary glasses by adding different amounts of CeO₂ to the components of the tellurium soda-borate glasses. The non-crystalline nature of the samples was validated by the X-ray diffraction patterns. The density of glass samples was determined by Archimedes principle, and hence other physical properties like polaron radius, oxygen packing density, and average boron-boron separation were calculated. The FTIR spectra demonstrated the presence of fundamental structural groups of borate (BO₃ and BO₄) and tellurite (TeO₄ and TeO₃) in both the undoped and doped samples. FTIR also demonstrated the presence of the unique structural group of cerium tetrahedral CeO₄ when the B₂O₃ level was decreased. The optical properties were analysed for the glass samples by the UV-Visible spectroscopy method. Refractive index (RI) of the glasses was found by using suitable mathematical approaches, and the highest RI value was found for BTNC5. Metallization criterion, optical basicity, electronegativity, and optical properties are determined with the help of the obtained RI and optical energy bandgap. The values of direct and indirect energy gaps, optical basicity, and refractive index were all impacted by the variation of CeO₂ content. The CeO₂-doped BTNC glasses allowed 5d → 4f transitions of Ce³⁺ ions and gave a wide green emission at 512 nm. The CIE diagram showed that CeO₂-doped BTNC glasses lie in the green to yellowish region. The CCT values are > 5000 K, indicating a cool CCT. The obtained results of optical and luminescence properties indicate that the BTNC glasses are potential candidates for light-emitting devices.