中国科学技术大学姚宏斌团队近日报道了三维钙钛矿异质结构助力高性能纯红光钙钛矿LED。相关论文于2025年5月7日发表在《自然》杂志上。

金属卤化物钙钛矿是下一代发光二极管（LED）颇有前景的发光候选材料。在纯红色钙钛矿LED（PeLEDs）中同时实现高亮度和高效率是一个持续的目标。三维CsPbI_3-xBr_x发射体具有出色的载流子传输能力和高色纯度，可以实现高效和超亮的纯红色PeLED。然而，这种器件容易出现效率骤降，导致在高电流密度下效率低、亮度低。

研究组利用电激发瞬态吸收光谱技术，发现了由空穴泄漏引起的效率骤降。因此，他们开发了CsPbI_3-xBr_x晶间异质结构，包含窄带隙发射体和宽带隙势垒来限域注入的载流子。通过在[PbX₆]⁴⁻框架中引入强键合分子来扩展三维CsPbI_3-xBr_x晶格，从而引入了宽带隙势垒。该策略产生了明亮高效的纯红色PeLED，具有24600 cd m⁻²的高亮度，24.2%的峰值外量子效率，以及极低的效率骤降，在22670 cd m⁻²的高亮度下仍保持10.5%的外量子效率。

附：英文原文

Title: Intragrain 3D perovskite heterostructure for high-performance pure-red perovskite LEDs

Author: Song, Yong-Hui, Li, Bo, Wang, Zi-Jian, Tai, Xiao-Lin, Ding, Guan-Jie, Li, Zi-Du, Xu, Huaiyu, Hao, Jing-Ming, Song, Kuang-Hui, Feng, Li-Zhe, Hu, Ya-Lan, Yin, Yi-Chen, Zhu, Bai-Sheng, Zhang, Guozhen, Ju, Huanxin, Zheng, Guanhaojie, Hu, Wei, Lin, Yue, Fan, Fengjia, Yao, Hong-Bin

Issue&Volume: 2025-05-07

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 24,600cdm2, maximum external quantum efficiency of 24.2% and low efficiency roll-off, maintaining a 10.5% external quantum efficiency at a high luminance of 22,670cdm2.

DOI: 10.1038/s41586-025-08867-6

Source: https://www.nature.com/articles/s41586-025-08867-6