Weakly space-confined all-inorganic perovskites for light-emitting diodes

• 成果类型: Article
• 署名作者: Peng, Chenchen; Yao, Haitao; Ali, Othman; Chen, Wenjing; Yang, Yingguo; Huang, Zongming; Liu, Hui; Li, Jianyu; Chen, Tao; Li, Zhijian; Sun, Mei; Zhou, Hongmin; Tao, Xiangru; Wang, Nana; Wang, Jianpu; Xiao, Zhengguo
• 署名单位: Chinese Academy of Sciences; University of Science & Technology of China, CAS; Fudan University; Chinese Academy of Sciences; University of Science & Technology of China, CAS; Chinese Academy of Sciences; University of Science & Technology of China, CAS; Nanjing Tech University; Nanjing Tech University; Changzhou University; Changzhou University
• 刊物名称: Nature
• ISSN/ISSBN: 0028-1419
• DOI: 10.1038/s41586-025-09137-1
• 发表日期: 2025-07-03
• 关键词: stability; energy

摘要

Metal halide perovskites are promising materials for light-emitting diodes (LEDs)1, 2, 3-4. Spatially confining charge carriers using nanocrystal/quantum dots5, 6, 7, 8-9, low-dimensional perovskites10, 11, 12-13 and ultrathin perovskite layers14 have all been used to improve the external quantum efficiency of perovskite LEDs (PeLEDs). However, most strongly space-confined perovskites suffer from severe Auger recombination, ion migration and thermal instability, resulting in limited brightness and operational lifetime6,7,10, 11-12,14, 15, 16-17. Here, we report an alternative strategy based on weakly space-confined, large-grained crystals of all-inorganic perovskite. Sacrificial additives, namely, hypophosphorous acid and ammonium chloride, were used to induce nucleation and crystallization of caesium lead bromide, resulting in monocrystal grains with minimized trap density and a high photoluminescence quantum yield. Benefiting from the high carrier mobility and suppressed Auger recombination, we obtained efficient PeLEDs with an external quantum efficiency reaching 22.0%, which remained above 20% at a high current density near 1,000 mA cm-2 and a brightness of over 1,167,000 cd m-2. Furthermore, benefiting from the suppressed ion migration and better thermal stability, the extrapolated half-lifetime of the weakly space-confined PeLEDs increased to 185,600 h under an initial luminance of 100 cd m-2 at room temperature. Our work is a new approach for designing efficient, bright and stable PeLEDs for real applications.