Color tunable and white light emitting via energy transfer in single-phase BiOCl:Er3+, Sm3+ phosphors for WLEDs

BiOCl crystal shows potential as efficient optical host due to its special layered structure. Here, the luminescence properties of the Er3+/Sm3+ co-doped BiOCl phosphors as single-phase phosphors were reported. Upon near ultraviolet excitation (NUV, 380 nm corresponding the I-4(15/2) -> (4)G(11/2) transition of Er3+ ions), the phosphors exhibit the efficient characteristic emissions of Er-3+ and Sm3+ ions simultaneously. The energy transfer (ET) from Er3+ to Sm3+ ions in the layered crystals has been validated by the variation of emission intensities and decay lifetimes respectively, which is ascribed to be a dipolee dipole interaction. By virtue of the ET behavior and increasing Sm3+ ion concentration, the enhancing emission intensity of Sm3+ and the tunability of emission color from yellowish-green (0.318, 0.420) to white (0.343, 0.347) are realized. The results of our work indicate that the Er3+/Sm3+ co-doped BiOCl phosphor has a promising application serving as single component white emitting phosphors for NUV excited WLEDs. (C) 2018 Published by Elsevier B.V. on behalf of Chinese Society of Rare Earths.