Near ultraviolet excited white light emitting diode (WLED) based on the blue LiCaPO4:Eu2+ phosphor

Abstract

Abstract One near ultraviolet (NUV) chip coated with tricolor phosphors to fabricate the white light emitting diode (WLED) has been attractive widely. In this paper, the blue emitting LiCaPO4:Eu2+, together with the red CaSiAlN3: Eu2+ and the green (Sr, Ba)SiO4: Eu2+ phosphor, is selected as the tricolor components for the NUV excited WLED preparation. The as-prepared WLED exhibits good luminescent performances with the color rendering index (Ra) of 88.6, the correlation color temperature of 3351\u202fK, the lumen efficiency of 77.05\u202flm/W, and the color coordinates located at (0.4399, 0.4389). It is worth mentioning that the blue-light of the warm WLED succeeds to keep away from the hazard zone centered at 450\u202fnm. Furthermore, a full spectrum warm WLED with the color rendering index (CRI) of 95.8 is fabricated by adding the fourth component as the Sr5(PO4)3Cl:Eu2+ phosphor. The prepared full spectrum WLED achieves the performance index of museum lighting.