The Optical Properties of Dy³⁺ Doped LaPO₄ Phosphors Prepared by Solid State Reaction Method

Abstract

Luminescent nanomaterials are used in everyday life due to their employment in distinct fields of science and technology, like cathode ray tubes (CRTs), flat panel display devices, temperature sensors, lasers, solar-cells, biological imaging, and solid-state lighting but also as carriers for miscellaneous therapeutic drugs. We have prepared dysprosium Dy³⁺ (0.5 mol %) doped lanthanum phosphate (LaPO₄) phosphor by solid state reaction method. The excitation spectra of synthesized phosphor at 595 nm monitoring were composed of broadband and a series of sharp peaks, the strongest excitation peak at 254, 271, and 350 nm. The main emission spectra of samples under 254, 271, and 350 nm excitation are Dy³⁺ (0.5 mol %) doped LaPO₄ phosphor observed at 477 and 573 nm corresponding to blue and yellow color. The broadband emission is the characteristic of the allowed f-h transition of Dy³⁺ ions. The corresponding emission band is observed due to the (blue emission) ⁴f_9/2→⁶h_15/2, (yellow emission) ⁴f_9/2→⁶h_13/2 transition of Dy³⁺ ions.  All the samples have been characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and photoluminescence (PL) techniques.