Highly emissive and color-tunable copper-based halide composites for bright white light-emitting diodes

The blue-emissive Cs 3 Cu 2 I 5 , yellow-emissive CsCu 2 I 3 , and white-emissive Cs 3 Cu 2 I 5 @CsCu 2 I 3 composites have been obtained by a one-step microwave method. The three UV-pumped WLEDs are fabricated by using the composites, and a CRI of 92 is achieved.