A novel red emitting phosphor of Eu3+ doped TTB-type niobate NaSr2Nb5O15 for white LEDs

Eu3+ doped NaSr2Nb5O15 series were firstly synthesized by solid-state reaction method. Crystal structure, characteristic luminescence properties as well as charge compensation mechanism are investigated detailedly by X-ray diffraction refinement and photoluminescence spectra measurement. NaSr2Nb5O15:Eu3+ exhibits strong absorption in near ultraviolet-blue region and intense red emission with CIE chromaticity coordinates (0.638, 0.355) after adding the charge compensation agent upon 398 nm excitation. The integral intensity of NSN:0.03Eu3+, 0.03Li+ is 64.5% of the commercial Y2O3:Eu3+ and the quantum efficiency is calculated to be 41.5%. The results show that NaSr2Nb5O15:Eu3+ can be a promising red-emitting phosphor for white LEDs.