Effect of Dopant Concentration on Luminescence Properties of Na3Ca2(SO4)3F: RE (RE = Eu3+, Dy3+) Phosphor for Solid-State Lighting

Abstract

A fluoride material phosphor doped with rare earth ions Eu³⁺ and Dy³⁺ was studied for its photoluminescence (PL) properties. The material was synthesized using a combustion method and characterized using X-ray diffraction (XRD) and PL techniques. The Na₃Ca₂(SO₄)₃F: Eu³⁺ phosphor exhibits two distinct peaks at 593 nm (orange) and 615 nm (red) at an excitation wavelength of 395 nm. The PL excitation spectrum of the Na₃Ca₂(SO₄)₃F: Dy³⁺ phosphor showed series of peaks, corresponding to the 4f → 4f transitions of Dy³⁺ ions. Under 350-nm excitation, the PL emission spectrum revealed two prominent bands one at 483 nm (blue region) due to the ⁴F₉_/₂ → ⁶H₁₅_/₂ transition, and another at 573 nm (yellow region) resulting from the ⁴F₉_/₂ → ⁶H₁₃_/₂ transition. These blue and yellow emissions suggest potential applications in solid-state lighting, particularly for mercury-free excitation sources. Rare earth–doped Eu³⁺/Dy³⁺ materials exhibit highly efficient PL properties, making them suitable candidates for white light-emitting diodes (LEDs) or other solid-state lighting phosphors.