Recent Advances in Light Outcoupling from Quantum-Dot Light-Emitting Diodes

Colloidal nanocrystal quantum-dot (QD)-based light-emitting diodes (QLEDs) represent a highly promising technology for next-generation displays, utilizing the distinctive optical characteristics of QDs to generate vivid and precise colors. For decades, extensive research efforts have been dedicated to the synthesis of QDs and the engineering of QLEDs, with the ultimate goal of making them practically applicable. Notably, the majority of research has concentrated on performance enhancements that are predominantly attributed to the intrinsic characteristics of the material, rather than its optical factors. However, it has become increasingly evident recently that, as with other electroluminescent devices, research to enhance the optical outcoupling of QLEDs is of profound importance for achieving high efficiency and brightness. This Perspective discusses recent cornerstones and major challenges in outcoupling technologies for QLEDs, particularly those based on microcavity structures. It also offers valuable insights into the future prospects of this emerging research area, including the modulation of angular emission profiles and an in-depth investigation of advanced exciton dynamics.