Groundbreaking solvent sieve method enhances perovskite light-emitting diode performance, achieving unprecedented efficiency and operational lifetime.
Using a simple solvent sieve method, researchers from the Ningbo Institute of Materials Technology and Engineering (NIMTE) of the Chinese Academy of Sciences (CAS) have taken the lead in developing highly efficient and stable perovskite light-emitting diodes (PeLEDs) with record performance.
The study was published today (February 5) in
Inspired by the process of separating sand of different sizes with a sieve, the researchers proposed a solvent sieve method to screen out these undesirable low n-phases.
According to the researchers, the solvent sieve is a combination of polar and nonpolar solvents. The polar solvent acts as a mesh that interacts with perovskites, while the nonpolar solvent acts as a framework that does not affect perovskites. The researchers adjusted the ratio of polar solvents to effectively remove the defective low n-phases.
Record-Setting Performance and Stability
The PeLEDs based on the sieved perovskites achieved an operating lifetime of more than 5.7 years under normal conditions (luminance of 100 cd/m2), more than 30 times longer than the untreated device. This record lifetime is also the highest value reported to date for green PeLEDs, reaching the fundamental threshold for commercial application.
In addition, these PeLEDs achieved a record high external quantum efficiency (EQE) of 29.5%, significantly improving the efficiency of converting electricity to light.
When exposed to ambient air (50±10% humidity), the device can maintain 75% of its film photoluminescence quantum yield and 80% of its EQE for more than 100 days, thus showing excellent stability.
This solvent sieve method not only significantly improves the luminescence performance and stability of PeLEDs, but also paves the way for the future development and application of perovskites with unique nanostructures and excellent luminescence performance.
Reference: “Phase dimensions resolving of efficient and stable perovskite light-emitting diodes at high brightness” by Shuo Ding, Qiangqiang Wang, Wencui Gu, Zhaobing Tang, Bo Zhang, Chunyan Wu, Xuanyu Zhang, Hao Chen, Xinyu Zhang, Rui Cao, Tao Chen, Lei Qian and Chaoyu Xiang, 5 February 2024, Nature Photonics.
DOI: 10.1038/s41566-023-01372-0