Enhancing performance of blue ZnTeSe-based quantum dot light-emitting diodes through dual dipole layers engineering

Blue ZnTeSe-based quantum dot light-emitting diodes (QLEDs) often suffer from poor hole injection, which significantly limits their performance. Herein, we introduced dual dipole layers consisting of (2, 3, 6, 7, 10, 11 hexaazatriphenyl hexacarbonitrile) (HAT-CN) between the hole injection layer of poly (3,4-ethylenedioxythiophene): poly (styrene sulfonate) (PEDOT: PSS) and hole transport layer of (polyvinylcarbazole) (PVK) to enhance the performance of blue ZnTeSe-based QLEDs. The introduction of the HAT-CN layer created dual dipole layers, which reduce the hole injection barrier between PEDOT: PSS and PVK, decrease the hole defect density, increase the hole current, and improve the effective radiation recombination of charge carriers. The QLEDs with the HAT-CN layer exhibited higher external quantum efficiency compared to those without the HAT-CN layer, increasing from 4.2% to 10.1%. Moreover, the T-50 lifetime almost doubled at a high luminance of 2000 cd m(-2). This work shows that introducing the HAT-CN layer to create dual dipole layers using the full solution method is an effective strategy for preparing high-performance ZnTeSe-based blue QLEDs.