Blue Light Emitting Diodes based on Bright Quasi-Type-II ZnO@1-Aminopyrene Hybrid Quantum Dots with a Long Operation Life

Abstract

Non-toxic heavy metal, low-cost indium-free blue emissive quantum dots (QDs) are critical for the realization of self-emissive electroluminescent quantum dot (ELQD) light-emitting diode (LED) displays. A facile and effective hybridization of ZnO QDs with functionalized polyaromatic hydrocarbons (f-PAHs) to synthesize a very bright and stable blue-light emissive quantum-dot LED (QLED) using non-toxic quasi-type-II ZnO@1-Aminopyrene hybrid QDs is reported. The optimized QLEDs of ITO/PEDOT:PSS/TFB/ZnO@1-Aminopyrene/TPBi/LiF/Al demonstrate very bright deep blue-light electroluminescence of 3379 cd m(-2) centered at lambda = 441 nm with a full-width-at-half maximum of 41.7 nm and CIE 1931 color coordinates of 0.17 and 0.09, a luminous efficacy of 3.32 cd A(-1), power efficiency of 2.45 lm W-1, external quantum efficiency of 2.35%, and a remarkably long lifetime T-50 of >17 830 h at 100 cd m(-2).