Highly Efficient Halide Perovskite Light‐Emitting Diodes via Molecular Passivation
Abstract
Metal halide perovskites are promising for applications in light‐emitting diodes (LEDs), but still suffer from defects‐mediated nonradiative losses, which represent a major efficiency‐limiting factor in perovskite‐based LEDs (PeLEDs). Reported here is a strategy to synthesize molecular passivators with different anchoring groups for defects passivation. The passivated perovskite thin films exhibit improved optoelectronic properties as well as reduced grain size and surface roughness, thus enable highly efficient PeLEDs with an external quantum efficiency of 15.6 % using an imidazolium terminated passivator. Further demonstrated is that the in situ formation of low‐dimensional perovskite phase on the surface of three‐dimensional perovskite nanograins is responsible for surface defects passivation, which leads to significantly enhanced device performance. Our results provide new fundamental insights into the role of organic molecular passivators in boosting the performance of PeLEDs.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Mar 04, 2021
- Source ID
- 10.1002/ange.202100243
Entities
People
- Aihui Liang
- Blake P Finkenauer
- Chenhui Zhu
- Kang L. Wang
- Letian Dou
- Libai Huang
- Linrui Jin
- Yao Gao
Organizations
- Jiangxi Normal University
- Lawrence Berkeley National Laboratory
- Office of Naval Research
- Purdue University