High luminance of CuInS2-based yellow quantum dot light emitting diodes fabricated by all-solution processing. Issue 76 (1st August 2016)

• Record Type: Journal Article
• Authors: Li, Jingling; Jin, Hu; Wang, Kelai; Xie, Dehui; Xu, Dehua; Xu, Xueqing; Xu, Gang
• Is Part Of: RSC advances. Volume 6:Issue 76(2016)
• Page Start: 72462
• Page End: 72470
• Publication Date: 2016-08-01
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c6ra14241a
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : In this work, all-solution processed, multi-layer yellow QLEDs, consisting of a hole transport layer of poly(9-vinylcarbazole), emissive layer of ligand exchanged CuInS2/ZnS QDs, and electron transport layer of ZnO nanoparticles, are fabricated. Abstract : In this work, all-solution processed, multi-layer yellow quantum dot light emitting diodes (QLEDs), consisting of a hole transport layer of poly(9-vinylcarbazole), emissive layer of CuInS2 /ZnS (ZCIS) QDs, and electron transport layer of ZnO nanoparticles, are fabricated. To improve the carrier-balance in QLEDs, a ligand-exchange strategy is employed to replace n -dodecanethiol that caps the surface of CuInS2 /ZnS quantum dots with 2-ethylhexanethiol. After this processing, improvement of current efficiency and external quantum efficiency of QLEDs is achieved. The optimized diodes exhibit a maximum luminance of 2354 cd m −2 and an external quantum efficiency of 0.63%, together with a lower turn-on voltage (decreases from 3.1 V to 2.7 V) using these ligand-exchanged QDs as emitting materials. Furthermore, CuInS2 -based QLEDs in our study exhibit color retainability with increasing voltage and prolonged use, and show great promise for practical application.