Regular Tandem Quantum Dot Light-Emitting Diodes with over 51% External Quantum Efficiency for Next-Generation
Dawei Yang1, Yiduo Wang1, Jing Xie1
1Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials, MOE Key Laboratory of New Processing Technology for Nonferrous Metals and Materials, and School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China.
Advanced Materials (Deerfield Beach, Fla.)
|August 16, 2025
Summary
Novel regular tandem quantum dot light-emitting diodes (QLEDs) achieve record efficiency and stability using an ultrathin indium tin oxide charge generation layer. This breakthrough enables high-performance displays and accelerates QLED applications.
Area of Science:
- Materials Science
- Optoelectronics
- Display Technology
Background:
- Regular tandem quantum dot light-emitting diodes (QLEDs) exhibit lower performance compared to inverted designs.
- Existing regular tandem QLEDs face challenges in efficiency, stability, and operational voltage.
Purpose of the Study:
- To develop high-performance regular tandem QLEDs with improved efficiency and stability.
- To investigate the impact of an ultrathin indium tin oxide (ITO) charge generation layer (CGL) on device performance.
- To demonstrate the potential of these devices in advanced display applications.
Main Methods:
- Fabrication of regular tandem QLEDs utilizing an ultrathin (≈4 nm) ITO CGL.
- Systematic optimization of charge injection balance and light out-coupling efficiency.
- Characterization of device performance, including external quantum efficiency (EQE), lifetime, turn-on voltage, and response time.
Main Results:
- Achieved a record-breaking EQE of 51.2% for regular tandem QLEDs.
- Demonstrated exceptional T95 lifetime of ≈31383 h at 1000 cd m⁻².
- Reported an ultralow turn-on voltage of 2.8 V.
- Successfully fabricated the first 8 × 8 passive-matrix display with flicker-free image presentation and fast response time (≈4.8 µs).
Conclusions:
- The developed ultrathin ITO CGL significantly enhances the performance of regular tandem QLEDs.
- These findings represent a major advancement for regular tandem QLED technology, surpassing previous benchmarks.
- The results pave the way for next-generation displays and lighting with improved efficiency and stability.
