MA Hang, LI Deng-hua, CHEN Wen-bai etc. Quantum Dot Light Emitting Diodes with ZnO Electron Transport Layer[J]. Chinese Journal of Luminescence, 2017,38(4): 507-513
MA Hang, LI Deng-hua, CHEN Wen-bai etc. Quantum Dot Light Emitting Diodes with ZnO Electron Transport Layer[J]. Chinese Journal of Luminescence, 2017,38(4): 507-513 DOI: 10.3788/fgxb20173804.0507.
Quantum Dot Light Emitting Diodes with ZnO Electron Transport Layer
In order to reduce the turn on voltage and improve the performance of QLED
ZnO film with good electronic transmission property was used as electron transport layer. The structure of the sample was ITO/PEDOT:PSS/Poly-TPD/QDs/ZnO. The models of Folwer-Nordheim tunneling injection and space-charge limited current were employed to analyze the injection current density in QDs layer. The results show that the optimal thickness of poly-TPD is confirmed to 40 nm when ZnO thickness is fixed of 50 nm
and the injection carriers in QDs layer can reach a certain balance. By measuring the current density-voltage-luminance-luminous efficiency of QLED
the influences of hole transport layer thickness on the device performance were studied. Experiment results show that the device with a hole transport layer of 40 nm has the best performances than the other devices
of which the turn on voltage is 1.7 V
the maximum lumious efficiency is 1.18 cd/A
and the maximum brightness can reach 5 225 cd/m
2
under the voltage of 9 V.
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references
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State Key Laboratory of Pollution Control and Resource Reuse, Department of Environmental Engineering, Nanjing University, Nanjing 210093, China
State Key Laboratory of Coordination Chemistry, Nanjing National Laboratory of Microstructures, School of Chemistry and Chemical Engineering, Nanjing University
Department of Physics, Quanzhou Normal College
National Laboratory of Integrated Optoelectronics, Jilin University