Rare Earth-Doped Perovskite Quantum Dot Microspheres for Micro-LED Displays

Cesium lead bromide perovskite quantum dots (PeQDs) have been recognized as promising color conversion materials for realizing high-performance green micrometer-scale light-emitting diodes (micro-LEDs) to address the "green gap" bottleneck in this field. However, whether their luminescence performance and stability meet the stringent requirements of micro-LED applications remains unclear. Furthermore, traditional PeQDs exhibit obvious luminescence saturation under high light power density excitation. To address these problems, we design and synthesize green-emitting Ce3+, K+ codoped CsPbBr3 perovskite microspheres by encapsulating codoped PeQDs in mesoporous silica spheres, demonstrating simultaneous near-unity photoluminescence quantum yields and exceptional overall stability. Green micro-LEDs, prepared by using the PeQD microspheres, achieve an external quantum efficiency of up to 19.54% and a high brightness of 4.26 × 107 cd m–2. Finally, green micro-LED arrays were integrated with a thin-film transistor backplane to fabricate a 0.6 in. micro-LED display.