Synthesis, photoluminescent properties, and an insight into the Judd-Ofelt analysis of the NaPbBi(2-x)(PO4)3: xEu3+ orthophosphate phosphors for light applications

Abstract

A set of novel reddish orange light emitting NaPbBi2(PO4)3: xEu3+ (hereafter referred to as NPbBP) phosphate phosphors were synthesized by the conventional solid state reaction route. The phase formation, particle morphology, elemental composition and the optical properties of the prepared phosphors were studied in detail from the powder XRD data, SEM images, EDS analysis, and the diffuse reflectance spectroscopy measurements respectively. The photoluminescence properties were systematically studied by recording the excitation and emission spectra of the prepared phosphors. The NPbBP: xEu3+ phosphors, excited at the near ultraviolet light, exhibited the reddish orange light emission in the visible region due to the dominance of magnetic dipole transition of the Eu3+ ions in the host. The details of the radiative properties were analyzed through the Judd- Ofelt intensity parameters, which were found to follow the trend of Ω2< Ω4. The thermal stability and the life time of the phosphors were investigated. The calculated photometric parameters of the NPbBP: 0.09Eu3+ phosphor suggested that the emission was found in the reddish-orange region with a high color purity and high quantum yield of 99.53% and 79.7% respectively. These results showed that the NPbBP: Eu3+ phosphor could serve as a good phosphor for use in various optoelectronic devices such as phosphor converted WLEDs, solar cells, and display panels.