Solution-Processed Double-Junction Quantum-Dot Light-Emitting Diodes with an EQE of Over 40
Piaoyang Shen1, Fan Cao1, Haoran Wang1
1Key Laboratory of Advanced Display and System Applications of Ministry of Education , Shanghai University , 149 Yanchang Road , Shanghai 200072 , China.
ACS Applied Materials & Interfaces
|December 20, 2018
Summary
High-performance tandem quantum-dot light-emitting diodes (QD-LEDs) were achieved using solution processing. These double-junction devices demonstrate excellent efficiency, rivaling vacuum-deposited organic LEDs.
Area of Science:
- Materials Science
- Optoelectronics
- Nanotechnology
Background:
- Single-junction quantum-dot light-emitting diodes (QD-LEDs) have advanced rapidly.
- Developing high-performance tandem QD-LEDs remains a significant challenge.
Purpose of the Study:
- To report solution-processed double-junction tandem QD-LEDs with high performance.
- To achieve efficiencies comparable to state-of-the-art vacuum-deposited tandem organic LEDs.
Main Methods:
- Interface engineering of optimized single light-emitting units to balance carrier transport/injection and suppress exciton quenching.
- Design of an effective interconnecting layer using a specific blend of polymers and modified ZnO.
Main Results:
- Achieved a high external quantum efficiency of 42.2%.
- Attained a high current efficiency of 183.3 cd A-1.
- Demonstrated performance comparable to the best vacuum-deposited tandem organic LEDs.
Conclusions:
- Solution-processed tandem QD-LEDs can achieve high performance through careful interface and interconnecting layer design.
- The developed QD-LEDs offer a promising alternative to vacuum-deposited devices.
Keywords:
electroluminescenceinterfacial engineeringlight-emitting diodesquantum dotstandem structureMore Related Videos
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