Li Ying, Xing Jun, Zhou Rongxue, Li Yixuan, Huang Ziyuan, Zhu Zhicheng, Zang Hang, Su Zhenhuang, Sun Xiaojuan, Yang Bai, Yu Weili, Li Dabing
State Key Laboratory of Luminescence Science and Technology, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, 130033, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
Small. 2025 Aug;21(34):e2501181. doi: 10.1002/smll.202501181. Epub 2025 Jun 26.
Crystal facet orientation plays a key role in dominating the optoelectronic conversion and stability of perovskite devices. To date, in-depth understanding on how to control the orientation of crystal facet and its' effect on the optoelectronic properties of perovskites remains a significant challenge. Here, a strategy for manipulating the facet orientation of methylammonium lead bromide (MAPbBr) perovskite single crystals utilizing carbon dots (CDs) is proposed, which can expose the (111) facet by reducing the surface energy of specific crystal facets selectively and improve the optoelectronic properties by CDs incorporation simultaneously. Experimental and theoretical studies indicate that the CDs are prefer to adsorb on the (111) facet and the (111) facet-dominated CDs-perovskite composite crystal matrixes exhibit significantly improved optoelectronic properties compared to perovskite crystal dominated by the (100) facet Consequently, the (111) facet-dominated perovskite photodetector demonstrates exceptional performance, with a responsivity as high as 249.09 A W and a detectivity of 1.19 × 10 Jones. More significantly, the unencapsulated photodetector shows remarkable stability, maintaining a record 93% of its initial performance over 90 d. This work provides a novel way to enhance the performance of halide perovskites photodetectors by crystal facet orientation modulation strategy, especially the stability.
晶面取向在决定钙钛矿器件的光电转换和稳定性方面起着关键作用。迄今为止，深入了解如何控制晶面取向及其对钙钛矿光电性能的影响仍然是一项重大挑战。在此，提出了一种利用碳点（CDs）操纵甲基溴化铅（MAPbBr）钙钛矿单晶晶面取向的策略，该策略可通过选择性降低特定晶面的表面能来暴露（111）晶面，并同时通过掺入CDs来改善光电性能。实验和理论研究表明，CDs更倾向于吸附在（111）晶面上，与以（100）晶面为主的钙钛矿晶体相比，以（111）晶面为主的CDs-钙钛矿复合晶体基质表现出显著改善的光电性能。因此，以（111）晶面为主的钙钛矿光电探测器表现出优异的性能，响应度高达249.09 A/W，探测率为1.19×10 Jones。更重要的是，未封装的光电探测器显示出卓越的稳定性，在90天内保持其初始性能的93%，创历史记录。这项工作通过晶面取向调制策略，特别是稳定性，为提高卤化物钙钛矿光电探测器的性能提供了一种新方法。
