Blue Quantum Dot Light-Emitting Diodes toward Full-Color Displays: Materials, Devices, and Large-Scale Fabrication

Quantum dots (QDs) light-emitting diodes (QLEDs) are gaining significant interest for the next generation of display and lighting applications because of their wide color gamut, cost-effective solution processability, and good stability. The last decades have witnessed rapid advances in improving their efficiency and lifetime. So far, among the three primary colors of QLEDs devices, the performance of blue QLEDs is considerably inferior to that of green and red ones including Cd-based and Cd-free devices, which is a key bottleneck hindering QLEDs' application. This mini-review describes recent advances of blue Cd-based and Cd-free QLEDs from materials to device engineering, in particular, elaborating the essential factors that limit their performance and the degradation mechanisms. We also discuss the progress and challenges of large-scale displays. Finally, we propose possible approaches to improve the performance of the blue QLEDs, including QDs materials and device architecture optimization, and summarize potential applications in this stimulating field.