Synthesis and Optical Characterization of Ce³⁺- Doped CaMgPO₄F Phosphor for LED Applications

In this study, CaMgPO 4 F nanophosphors doped with varying concentrations of cerium (2.1, 2.3, 2.5, and 2.7 mol%) were synthesized via a solid-state reaction method. The structural and optical properties of the synthesized phosphors were systematically investigated using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and UV–visible diffuse reflectance spectroscopy (UV-DRS). XRD analysis confirmed the phase purity and revealed a decrease in average crystallite size with increasing cerium content, indicating an inhibitory effect on crystal growth. FTIR spectroscopy identified the characteristic vibrational functional groups of the phosphor matrix. UV-DRS analysis revealed that the band gap energy increased from 2.93, 3.09, 3.01, 2.91 and 2.94 eV with higher cerium concentrations, indicating alterations in the electronic structure. Photoluminescence studies showed that the excitation at 401 nm and emission at 441.5, 499.5, and 650 nm; resulting in a pinkish red light emission. The CIE chromaticity coordinates further confirmed the color purity and consistency of the emitted light. These results highlight the potential of cerium-doped CaMgPO 4 F nano phosphors for use in LED applications, where specific color output and high emission intensity are essential for improved lighting performance.