Inverted Quantum Dot Light Emitting Diodes using Polyethylenimine ethoxylated modified ZnO

• DOI: 10.1038/srep08968
• Publication Date: 2015-03-10T10:23:55Z
• Authors: Hong Hee Kim; Soohyung Park; Yeonjin Yi; Dong Ick Son; Cheolmin Park; Do Kyung Hwang; Won Kook Choi
• Keywords: Polyethylenimine

Abstract Colloidal quantum dots (QDs) are an emerging class of new materials due to their unique physical properties. In particular, colloidal QD based light emitting diodes (QDLEDs) have been extensively studied and developed for the next generation displays solid-state lighting. Among a number approaches improve performance QDLEDs, most practical one is optimization charge transport balance in recombination region. Here, we suggest polyethylenimine ethoxylated (PEIE) modified ZnO nanoparticles (NPs) as electron injection layer inverted structure red CdSe-ZnS QDLED. The PEIE surface modifier, incorporated on top NPs film, facilitates enhancement both into emissive by lowering workfunction from 3.58 eV 2.87 emitter. As result, this device exhibits low turn-on voltage 2.0–2.5 V has maximum luminance current efficiency values 8600 cd/m 2 1.53 cd/A, respectively. same scheme with NPs/PEIE also used successfully fabricate green, blue white QDLEDs.