Preparation and luminescence properties of white light-emitting phosphors LaAl2.03B4O10.54: Dy3+

Abstract

A series of novel white light-emitting LaAl2.03B4O10.54: Dy3+ phosphors for light-emitting diode applications were synthesized by high-temperature solid-state reactions. The results of X-ray diffraction measurement indicate that the crystal structure of the phosphors is LaAl2.03B4O10.54. The photoluminescence spectra of Dy3+-doped samples under the excitation at 347 nm consist of two main groups of emission lines peaking at 480 and 571 nm, which can be assigned to the optical transitions 4F9/2 → 6H15/2 and 4F9/2 → 6H13/2 of Dy3+, respectively. Based on the recorded UV–visible diffuse reflectance spectra, the values of the optical band gaps of LaAl2.03B4O10.54 and La0.96Al2.03B4O10.54: 0.04 Dy3+ were ascertained to be 3.87 and 3.62 eV, respectively. The decay lifetimes decreases with the increasing doping concentration of Dy3+. The Commission International de I’Eclairage color coordinates of Dy3+-doped samples fall in the white region. The study about the photoluminescence spectra at rising temperature shows that our phosphors own excellent thermal stability. All these investigation results indicate that LaAl2.03B4O10.54: Dy3+ as white light-emitting phosphor has potential applications in white light-emitting diodes.