Investigation on luminescence characteristics of Dy3+-Tb3+ co-doped phospho-tellurite glasses for tunable green/ white LED applications

Abstract

Dy³⁺/Tb³⁺ co-doped glasses have drawn profound attention for their potential in solid state lighting due to their unique luminescence properties. This research highlights the effect of compositional variation on structural and optical characteristics of Dy³⁺/Tb³⁺ co-doped phospho-tellurite glasses through a comprehensive analysis involving X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and photoluminescence (PL) studies. XRD and FTIR spectroscopy are conducted to characterize the glass matrix and confirm its structural integrity. Luminescence spectroscopy is used to explicate the emission mechanism of the present glass system, revealing significant decrement in both intensity (Dy³⁺ & Tb³⁺) and wavelength tunability when glass network is modified by monovalent (Na⁺) to trivalent (B³⁺) compounds. Photoluminescence measurements provide insights into the glass system for the efficient energy transfer between Dy³⁺ and Tb³⁺ ions, leading to strong visible (yellow & green) emissions. The luminescence decay kinetics is analyzed to understand the dynamic processes, governing the emission lifetimes and energy transfer mechanisms. Additionally, CIELab color coordinates are employed to assess the colour purity and tunability of the emitted light. The outcomes suggest that the present glasses offer promising attributes for multicolor light generation, paving a pathway towards optimizing material design in the field of solid state lighting.