Synchrotron, luminescence, and XPS studies of Gd³⁺:Dy³⁺:Ce³⁺ tri-rare-earth oxides in borate glasses

Synchrotron studies were employed to understand the oxidation state and coordination chemistry of the Ce³⁺ ions which when added with Dy³⁺- co-doped calcium zinc gadolinium borate glasses prepared by conventional melt quenching technique. X-ray photoelectron spectroscopy was employed to understand the coordination chemistry of the prepared glass samples. Detailed analysis was investigated to understand the glass's optical properties such as density, refractive index, molar volume, field strength, inter-ionic radius, and average boron-boron distance. Using optical absorption studies, the Judd-Ofelt parameters were obtained, and radiative properties were evaluated and compared with other reported literature through the JO parameters. Photoluminescence and X-ray luminescence studies show similar results and found that the 575 nm corresponds to the electric-dipole transition of ⁴F_9/2 → ⁶H_13/2. Asymmetry ratio (Y/B) was evaluated to understand their covalency around the rare-earth ion. Lifetime analysis for Dy³⁺ and Gd³⁺ ions were able to probe and analyzed with a comparison of other reported glasses. CIE chromaticity diagram was able to plot for the prepared glass samples to bring about the (x, y) significance which provides their color coordinate temperature (CCT) values and compared with other glasses.