2025-05-08 中国科学院（CAS）
＜関連情報＞
- https://english.cas.cn/newsroom/research_news/phys/202505/t20250508_1042708.shtml
- https://www.nature.com/articles/s41586-025-08867-6
高性能純赤色ペロブスカイトLEDのための粒内3Dペロブスカイトヘテロ構造 Intragrain 3D perovskite heterostructure for high-performance pure-red perovskite LEDs
Yong-Hui Song,Bo Li,Zi-Jian Wang,Xiao-Lin Tai,Guan-Jie Ding,Zi-Du Li,Huaiyu Xu,Jing-Ming Hao,Kuang-Hui Song,Li-Zhe Feng,Ya-Lan Hu,Yi-Chen Yin,Bai-Sheng Zhu,Guozhen Zhang,Huanxin Ju,Guanhaojie Zheng,Wei Hu,Yue Lin,Fengjia Fan & Hong-Bin Yao
Nature Published:07 May 2025
DOI:https://doi.org/10.1038/s41586-025-08867-6
Abstract
Metal-halide perovskites are promising light-emitter candidates for next-generation light-emitting diodes (LEDs)1,2,3,4,5,6,7,8. Achieving high brightness and efficiency simultaneously in pure-red perovskite LEDs (PeLEDs) is an ongoing goal9,10. Three-dimensional (3D) CsPbI3-xBrx emitters have excellent carrier transport capability and high colour purity, which could allow efficient and ultrabright pure-red PeLEDs. However, such devices are prone to efficiency roll-off, resulting in low efficiency and low brightness under high current density. Here, by using electrically excited transient absorption spectroscopy, we discovered the efficiency roll-off was induced by hole leakage. Therefore, we developed a CsPbI3-xBrx intragrain heterostructure containing narrow bandgap emitters and wide bandgap barriers to confine the injected carriers. The wide bandgap barrier was incorporated by introducing strongly bonding molecules into the [PbX6]4− framework to expand the 3D CsPbI3-xBrx lattice. This strategy resulted in bright and efficient pure-red PeLEDs, with a high brightness of 24,600 cd m−2, maximum external quantum efficiency of 24.2% and low efficiency roll-off, maintaining a 10.5% external quantum efficiency at a high luminance of 22,670 cd m−2.
