Submicron Perovskite Quantum Dot Glass Microspheres for Micro-LED Displays

Quantum-dot (QD) color-conversion technology is considered a promising strategy for constructing a full-color micro-LED display. Perovskite quantum dots (PQDs) are the preferred luminescent materials for constructing color-conversion micro-LED pixels, but their poor environmental stability severely limits their practical application in micro-LED displays. Here, we design a novel submicron-sized PQD glass microspheres (PQDGMS) with high quantum yield and excellent stability for color conversion micro-LED displays. Kilogram scale (batch 2 kg) submicron-sized PQDGMS was prepared by a top-down strategy including melt-quenching, secondary recrystallization, and optimized submicronization processes. Ultra-stability of the PQDGMS was attributed to the passivation and self-healing effects of PQDs by AgBr additive, and the protection effect of the glass matrix around PQDs. The prepared PQDGMS has excellent environmental stability, with PL intensity maintained over 95% after immersion in water for 10 000 h, over 82% at a temperature of 100°C, and over 86% under continuous blue light irradiation (800 W m^-2) for 240 h. We prepared the PQDGMS color conversion pixels in a patterned through-hole glass substrate via capillary filling assistance and constructed color conversion green and red micro-LED chips with external quantum efficiency of 24.8% and 16.7%, respectively.