Dysprosium Ion Concentration Variations and their Comprehensive Influence on the Physical, Structural and Optical Properties of Multi-Component Borate Glasses for Luminescence Tailoring

A set of Zinc Strontium Lithium Fluoroborate (ZSLFB) glasses with different concentrations of Dysprosium ions (Dy³⁺) was created using the melt quench technique. The presence of non-crystallinity and various functional groups have been confirmed via X-Ray Diffraction (XRD) and Infrared Fourier Transform FT-IR measurements, respectively. The band gap values obtained from Tauc's plot were utilized to analyze the optical characteristics. The photoluminescence (PL) emission spectra display three well-defined intensity peaks at wavelengths of 481, 574, and 664 nm. The intensity of peaks exhibits an ascending trend until a concentration of 0.5 mol% of Dy³⁺ ions is reached, after which it decreases. The PL intensity maintains up to 82% at 200^o C to room temperature, showing excellent thermal stability. The Judd Ofelt (J-O) parameter values pursue the Ω₂ > Ω₆ > Ω₄ pattern, which shows its asymptotic nature. The CIE coordinates were assessed and determined to fall inside the white region. The interaction in the non-radiative energy transfer process was elucidated by utilizing the Dexter theory and Inokuti-Hiryama (I-H) model.