Sm3+ activated Ba3LaNa(PO4)3F fluorophosphate phosphor: Synthesis, characterization and their photoluminescence investigation for warm WLEDs

Abstract

In this present research report, the series of Ba₃LaNa(PO₄)₃Fphosphor doped with Sm³⁺ was successfully synthesized by using a high-temperature solid-state reaction method. The phase purity was examined using X-ray diffraction (XRD), which confirmed a pure phase of prepared material after sintering the sample at 700 °C. Fourier transform infrared (FT-IR) spectra showed absorption bands corresponding to the stretching and vibrational modes of PO₄ in phosphate. Scanning electron microscopy (SEM) images displayed the morphology of sample and agglomerated structure of micron-sized particles. Photoluminescence excitation (PLE) and emission spectra of the Ba₃LaNa(PO₄)₃F: Sm³⁺ phosphors were studied. When excited with near-UV light, the phosphor showed three prominent peaks at 567, 604, and 643 nm. The emission spectra for different concentrations of Sm³⁺ ions were also measured to find the optimal dopant concentration. The highest intensity was observed at a 2.0 mol% concentration of Sm³⁺ ions at 604 nmwith concentration quenching occurring beyond this point. The CIE chromaticity coordinates for the different concentration phosphor were located in the orange-red region, indicating its characteristic light emission. So therefore, these results suggested that the synthesized reddish-orange light-emitting Ba₃LaNa(PO₄)₃F: Sm³⁺prepared phosphor is promising for applications in white light-emitting diodes (WLEDs).