Hole injection of quantum dot light-emitting diodes facilitated by multilayered hole transport layer

Highlight• Multilayered HTL constructed by inserting thin MoO₃ into an organic layer. • Multilayered HTL exhibits high hole conductivity compared to monostructured HTL. • The QLEDs with multilayered HTL exhibited enhanced efficiency and lifetime. • Multilayered HTL denoted high electrical stability with 15 times enhanced lifetime. We report a multilayered hole transport layer (HTL) structure to improve the efficiencies and lifetimes of quantum dot light-emitting diodes (QD-LEDs). The HTL structure was constructed by inserting molybdenum trioxide (MoO₃) into an organic monolayer to enhance its hole conductivity. We then investigated the effects of the multilayered HTL on the performance and operating lifetimes of QD-LEDs. QD-LEDs with optimal HTL exhibit power efficiency, external quantum efficiency, and lifetime (T₈₀) of 10.19 lm/W, 9.66%, and 336 h, respectively. Compared to the monolayer structure, the lifetime of the multilayered HTL was enhanced by a factor of 15. This novel architecture for QD-LEDs with multilayered HTL offers a new design strategy for next-generation high-efficiency QLED displays and solid-state lighting technologies.