title: Highly efficient blue-green quantum dot light-emitting diodes using stable low-cadmium quaternary-alloy ZnCdSSe/ZnS core/shell nanocrystals.
abstract: High-quality blue-green emitting ZnxCd(1-x)S(1-y)Se(y)/ZnS core/shell quantum dots (QDs) have been synthesized by a phosphine-free method. The quantum yields of as-synthesized ZnxCd(1-x)S(1-y)Se(y)/ZnS core/shell QDs can reach 50-75% with emissions between 450 and 550 nm. The emissions of such core/shell QDs are not susceptible to ligand loss through the photostability test. Blue-green light-emitting diodes (LEDs) based on the low-cadmium ZnxCd(1-x)S(1-y)Se(y)/ZnS core/shell QDs have been successfully demonstrated. Composite films of poly[9,9-dioctylfluorene-co-N-[4-(3-methylpropyl)]-diphenylamine] (TFB) and ZnO nanoparticle layers were chosen as the hole-transporting and the electron-transporting layers, respectively. Highly bright blue-green QD-based light-emitting devices (QD-LEDs) showing maximum luminance up to 10000 cd/m(2), in particular, the blue QD-LEDs show an unprecedentedly high brightness over 4700 cd/m(2) and peak external quantum efficiency (EQE) of 0.8%, which is the highest value ever reported. These results signify a remarkable progress in QD-LEDs and offer a practicable platform for the realization of QD-based blue-green display and lighting.
authors: Key Laboratory for Special Functional Materials, Henan University, Kaifeng 475004, P R China.
authors: Huaibin
authors: H
authors: Shen
authors: Sheng
authors: S
authors: Wang
authors: Hongzhe
authors: H
authors: Wang
authors: Jinzhong
authors: J
authors: Niu
authors: Lei
authors: L
authors: Qian
authors: Yixing
authors: Y
authors: Yang
authors: Alexandre
authors: A
authors: Titov
authors: Jake
authors: J
authors: Hyvonen
authors: Ying
authors: Y
authors: Zheng
authors: Lin Song
authors: LS
authors: Li