Effect of Ba co-doping on Sr_5(PO_4)_3Cl:Ce3+ Blue Emitting Phosphor Application for White Light Emitting Diodes

摘要

Ce~(3+)-activated Sr_(5-2x-y)Ba_y(PO_4)_3Cl:xCe~(3+),xNa~+ phosphors were synthesized via the solid statereaction methods. The substitution of Ba~(2+) for Sr~(2+) ions was confirmed by Raman spectra. The broadest Raman width in Sr_2.45Ba_2.45(PO_4)_3Cl:Ce~(3+) phosphor supported its highest disorder of the host lattice, leading to the emission spectral broadening with a half width of 95.5 nm due to the larger variation in crystal filed strength. The thermal stability of the luminescence was evaluated by the temperature-dependent luminescence intensity. The simulating a spectra of blue-emitting Sr_2.45Ba_2.45(PO_4)_3Cl:0.05Ce~(3+),0.05Na~+ and orange emitting Sr_3SiO_5:Eu~(2+) phosphors as light converters, an intense white GaN-based near-UV-LED (400 nm) was exhibit good color-rendering index Ra of 90.8 at a correlated color temperature of 6473 K and CIE coordinates of (0.3165, 0.3051). These characteristics makes Sr_2.45Ba_2.45(PO_4)_3Cl: 0.05Ce~(3+), 0.05Na~+ should be a promising blue-emitting phosphors for the production of white light in phosphor conversion white-LEDs.