Efficient Red/Green/Blue Tandem Quantum-Dot Light-Emitting Diodes with External Quantum Efficiency Exceeding 21
Heng Zhang1, Shuming Chen1, Xiao Wei Sun1
1Department of Electrical and Electronic Engineering, Southern University of Science and Technology , Shenzhen, 518055, People's Republic of China.
ACS Nano
|December 19, 2017
Summary
Researchers developed highly efficient tandem quantum-dot light-emitting diodes (QLEDs) using a novel interconnecting layer (ICL). These QLEDs achieve record-breaking efficiencies for full-color displays and lighting applications.
Area of Science:
- Materials Science
- Optoelectronics
- Nanotechnology
Background:
- Quantum-dot light-emitting diodes (QLEDs) offer promising alternatives for display and lighting technologies.
- Achieving high efficiency and stable performance in full-color QLEDs remains a challenge.
Purpose of the Study:
- To develop highly efficient full-color tandem QLEDs.
- To investigate the performance enhancement enabled by a novel interconnecting layer (ICL).
Main Methods:
- Fabrication of tandem QLEDs utilizing a ZnMgO/Al/HATCN/MoO3 interconnecting layer.
- Characterization of the ICL's properties, including transparency, charge generation/injection, and solvent resistance.
- Performance evaluation of red, green, and blue QLEDs, including current efficiency, external quantum efficiency (EQE), and luminance stability.
Main Results:
- The developed ICL demonstrated high transparency, efficient charge handling, and solvent resistance.
- Record-breaking current efficiencies and EQEs were achieved for red, green, and blue QLEDs, exceeding 21% EQE for all colors.
- High efficiency was maintained across a wide luminance range, with minimal roll-off at high brightness.
Conclusions:
- The novel ICL significantly enhances the performance of tandem QLEDs.
- The demonstrated full-color tandem QLEDs exhibit superior efficiency, stability, and color purity.
- These findings position tandem QLEDs as strong candidates for next-generation displays and solid-state lighting.
