Efficient and stable near-infrared InAs quantum dot light-emitting diodes

Abstract

Abstract Visible quantum dot light-emitting diodes have satisfied commercial display requirements. However, near-infrared counterparts considerably lag behind due to the inferior quality of near-infrared quantum dots and limitations in device architecture suitable for near-infrared electroluminescence. Here, we present an efficient strategy using zinc fluoride to balance ZnSe shell growth across different core quantum dot facets, producing highly regular InAs/InP/ZnSe/ZnS quantum dots with near-unity quantum yield. Moreover, we develop a method of in-situ photo-crosslinking blended hole-transport materials for accurate energy level modulation. The crosslinked hole-transport layers enhance hole transfer to the emitting layer for balanced carrier dynamics in quantum dot light-emitting diodes. The resulting near-infrared quantum dot light-emitting diodes exhibit a peak external quantum efficiency of 20.5%, a maximum radiance of 581.4 W sr−1 m−2 and an operational half-lifetime of 550 h at 50 W sr−1 m−2. This study represents a step towards practical application of near-infrared quantum dot light-emitting diodes.