Structural and luminescence performance of the Eu3+ doped alkaline combined metal oxide-based sodium phosphate phosphors; NaMPO4 (M = Mg, Ba, and Ca) for LED applications

Abstract

The present research module is about the synthesis of Eu3+ ions-doped NaMPO4(M = Mg, Ba, and Ca) phosphate phosphors by the solution combustion synthesis method. The phase formation and chemical structures of alkaline combined metal oxide-based sodium phosphate phosphors are characterised by X-ray powder diffraction (XRD) and FT-IR measurements. Optimized crystal geometries were generated by employing VESTA software. The crystallite size was calculated from the full width at half maximum (FWHM) of the diffraction peak using the Scherrer formula. G-Fourier transformation software (G-FT) was adopted for generating electron density mapping of NaMgPO4 phosphors, 2D mapping, and 3D chicken plots showing crystal sites occupied by the compound’s constituent elements. The particle size distribution was confirmed by XRD diffraction, and SEM analysis found approximately 12 μm. UV–visible and photoluminescence spectroscopy uncover the optical traits of the prepared phosphor. Photo-emissions of Eu3+doped alkaline combined metal oxide-based sodium phosphate phosphors were monitored at possible excitation wavelengths. The orange-red peak observed at 592 nm and 598 nm occurs due to 5D0-7F1 electric dipole transitions. The peak observed at 618 nm corresponds to the forbidden f-f transitions 5D0-7F2. It is worth mentioning that absorption bands originating from the corresponding 5D0-7F2 transition widen the band region; hence, the stark effect becomes complicated. A low-intensity peak of 688 nm was observed in the NaCaPO4 phosphors, attributed to the 5D0-7F3 transition. Chromaticity coordinates and energy level transitions may determine the colour emission materials. The CIE coordinates of NaMPO4:Eu3+phosphors exhibit reddish emission and find application in light-emitting diodes (LEDs) and illuminating displays.