Development of Eu-doped NaCa(PO3)3 red-emitting phosphors for WLED applications

Abstract

The Eu-doped NaCa(PO₃)₃ red-emitting phosphors are prepared by the solid-state reaction method in two heating steps. Initially, the phosphor is heated to 300 °C to remove ammonia, followed by further heating at 730 °C temperature. The X‑ray diffraction (XRD) confirms the triclinic structure and surface morphology is detected by scanning electron microscopy (SEM). The Fourier transform infrared spectroscopy (FTIR) detects the molecular vibrations and chemical bonds present within the phosphors. The photoluminescence (PL) emission occurs at wavelengths of 593 and 616 nm when excited with 396 nm light. The PL intensity reaches its maximum at a 4 mol% concentration of Eu doping, and the color purity is high at 98.9% for this concentration.