Enhanced Luminance of CdSe/ZnS Quantum Dots Light-Emitting Diodes Using ZnO-Oleic Acid/ZnO Quantum Dots Double Electron Transport Layer
Abstract
:1. Introduction
2. Materials and Methods
2.1. Synthesis of ZnO Quantum Dots
2.2. Synthesis of ZnO-Oleic Acid (OA) QDs
2.3. QLEDs and Electron (Hole)-Only Device Fabrication
2.4. Characterization
3. Results and Discussions
3.1. Synthesis of ZnO Quantum Dots
3.2. Surface Chemistry
3.3. Optical Properties
3.4. Electronic Energy Level Structure
3.5. Improved EL of CdSe/ZnS QLEDs by Optimization of ETL
3.5.1. QLEDs with a Single ETL
3.5.2. Interface Morphology
3.5.3. EL with a Double ETLs
3.5.4. EOD and HOD
3.5.5. Conduction Mechanism
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Layer | Spin Coating (rpm) | Turn-On (V) | Maximum Luminance (cd/m2) | Current Efficiency (cd/A) |
---|---|---|---|---|
ZnO-OA (0.5 mL)/ZnO | 3000/4000 | 3.5 | 23,760 | 5.08 |
ZnO-OA (0.5 mL)/ZnO | 4000/4000 | 3.0 | 24,430 | 7.64 |
ZnO-OA (0.5 mL)/ZnO | 5000/4000 | 3.5 | 27,890 | 8.57 |
ZnO-OA (1.0 mL)/ZnO | 3000/4000 | 4.0 | 25,940 | 5.84 |
ZnO-OA (1.0 mL)/ZnO | 4000/4000 | 4.5 | 26,923 | 7.37 |
ZnO-OA (1.0 mL)/ZnO | 5000/4000 | 5.0 | 26,980 | 7.48 |
ZnO single layer | 4000 | 4.5 | 25,570 | 6.32 |
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Lee, D.Y.; Kim, H.H.; Noh, J.-H.; Lim, K.-Y.; Park, D.; Lee, I.-H.; Choi, W.K. Enhanced Luminance of CdSe/ZnS Quantum Dots Light-Emitting Diodes Using ZnO-Oleic Acid/ZnO Quantum Dots Double Electron Transport Layer. Nanomaterials 2022, 12, 2038. https://doi.org/10.3390/nano12122038
Lee DY, Kim HH, Noh J-H, Lim K-Y, Park D, Lee I-H, Choi WK. Enhanced Luminance of CdSe/ZnS Quantum Dots Light-Emitting Diodes Using ZnO-Oleic Acid/ZnO Quantum Dots Double Electron Transport Layer. Nanomaterials. 2022; 12(12):2038. https://doi.org/10.3390/nano12122038
Chicago/Turabian StyleLee, Da Young, Hong Hee Kim, Ji-Hyun Noh, Keun-Yong Lim, Donghee Park, In-Hwan Lee, and Won Kook Choi. 2022. "Enhanced Luminance of CdSe/ZnS Quantum Dots Light-Emitting Diodes Using ZnO-Oleic Acid/ZnO Quantum Dots Double Electron Transport Layer" Nanomaterials 12, no. 12: 2038. https://doi.org/10.3390/nano12122038