Study on the Structural and Optical Properties of Dy³⁺-doped Sodium Fluoroborate (NaFB2O3) Glass

Abstract

Sodium fluoroborate (NaFB2O3) glass doped with Dy³⁺ was successfully fabricated by melting method at 1020 oC in reducing environment using graphite. The structure and optical properties of the glass were studied by optical spectroscopy methods such as X-ray diffraction, Fourier transform infrared (FTIR), UV-VIS-NIR absorption spectroscopy, photoluminescence (PL) spectroscopy, etc. By using Judd-Ofelt theory, experimental (fexp) and calculated (fcal) oscillator force, Judd-Ofelt intensity parameters Ωλ (λ = 2, 4, 6) were evaluated from the absorption spectrum. The radiant properties such as fluorescence intensity ratio R, total emission transition probability AT, emission cross section σ and branching ratio βR (of the 4F9/2 → 6H13/2 transition) of the glass were also calculated from the fluorescence spectrum. Using McCamy's quantitative equation, the color coordinate and color temperature values from the combined emission of Dy3+ ions in the form of neutral white light when excited by 351 nm radiation were obtained. The results showed that the NaFB2O3:Dy3+ glass is a suitable
candidate for applications in the field of lighting (W-LED), materials for lasers or UV sensors.