Warm white light-emitting diodes using organic-inorganic halide perovskite materials coated YAG:Ce3+ phosphors

This work reports warm white light-emitting diodes (WLEDs) using organic-inorganic halide perovskite materials coated YAG:Ce3+ phosphors by a liquid phase synthesis method. The perovskite MAPbBr(3-x)I(x)-coated YAG:Ce3+ phosphors have more red light contribution than YAG:Ce3+ phosphors without the perovskite coating. The chromaticity coordinate of white LED with YAG:Ce3+ remote phosphor is (x = 0.3134, y = 0.3497) 6359. However, those of MAPbBr(2.5)I(0.5) and MAPbBr(2.0)I(1.0)-coated YAG:Ce3+ remote phosphor shift to (x = 0.4220, y = 0.3725) 2908 and (x = 0.4067, y = 0.4028) 3525, respectively. The colors of perovskite-coated samples are more red and warm. Therefore, the perovskite-coated YAG:Ce3+ method is useful for warm WLED.