Electroluminescent Quantum Dot Light-Emitting Diodes with ZnO and MoO₃ Carrier Transport Layers

Abstract:

In this article, the quantum dot (QD) light emitting diodes (QDLEDs) with ZnO electron transport layer (ETL) and MoO₃ hole transport layer (HTL) were demonstrated. The ZnO ETL was fabricated by sol-gel method. To achieve balanced electron and hole injection, hole transport materials including 4,4'-di(N-carbazolyl)biphenyl (CBP) and MoO₃ were also adapted. The device structure can be simply depicted as indium tin oxide (ITO)/ZnO/Cs₂CO₃/QD/CBP/MoO₃/Au. It was found that the Cs₂CO₃ played an important role to facilitate radiative recombination and reduce the leakage current due to the poor quality of sol-gel fabricated ZnO thin film. Via inserting an annealed Cs₂CO₃ buffer layer with proper thickness, red-emitting QDLEDs with low luminance turn-on voltage of 4.1 V and luminance larger than 100 cd/m₂ could be obtained. With our demonstration, QDLEDs with ZnO ETL can be a promising device structure for realizing QDLED’s commerizing.

• Periodical: Advanced Materials Research (Volume 677)
• Pages: 98-102
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.677.98
• Online since: March 2013
• Authors: Chun Yuan Huang, Ping Hua Tsai, Ying Chih Chen, Hsin Chieh Yu, Yan Kuin Su
• Keywords: Cesium Carbonate, Colloidal Quantum Dots, Light Emitting Diode (LED), Sol-Gel Synthesis

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