Optimized photoluminescence and electronic properties of europium doped phosphate red phosphor

Abstract

The exploration of red inorganic phosphor component with excellent performance for the development of the display domain is a scientific focus in recent years. In this work, NaAlP2O7:xEu3+ (x = 0, 1, 3, 5, 7, 9, 11, 13%) phosphors have been synthesized using a facile solid-state reaction method. In the solid solution, Eu3+ ion successfully replaces Na+ ion in NaAlP2O7 host. To determine absorption properties of pure and Eu3+ doped NaAlP2O7, theoretical computations and diffuse reflectance absorption measurements have been implemented. Photoluminescence spectra show the red light emission under the broad irradiation wavelength region from near-UV to visible light. Under near-UV light (395 nm) excitation, it exhibits a strong red light emission peaking at 612 nm (5D0 → 7F2 of Eu3+). The emission intensity reaches maximum at doping level of 9 mol% Eu3+, and the concentration quenching mechanism have been discussed in detail. For NaAlP2O7:9%Eu3+, the color purity of the red light is as high as 90%, and the internal quantum efficiency is 35.8%. The performances mean that NaAlP2O7:Eu3+ materials may be potentially applied as red phosphor for near-UV white LEDs. Keywords: Phosphate, Phosphor, Photoluminescence, White light emitting diodes