Ma Yu, Li Wenjing, Liu Yi, Guo Wuqian, Xu Haojie, Tang Liwei, Fan Qingshun, Wei Linjie, Luo Junhua, Sun Zhihua
State Key Laboratory of Functional Crystals and Devices, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian, 350002, P. R. China.
Chinese Academy of Sciences, University of Chinese Academy of Sciences, Beijing, 100039, P. R. China.
Adv Sci (Weinh). 2025 Jun 25:e07588. doi: 10.1002/advs.202507588.
Heterostructure single crystals have emerged as a significant functional material system due to their unique properties and potential for novel optoelectronic device applications. Particularly, their distinctive structural characteristics offer promising prospects for suppressing ion migration, which is highly advantageous for X-ray detection. Herein, by gradually modifying the cyclohexylmethylamine cation into the 4-aminomethyltetrahydropyran cation, a layered heterostructure single crystal (PbCl)(4-Aminomethyltetrahydropyran)PbCl is successfully obtained. It comprises two distinct inorganic frameworks, namely a perovskite layer built from PbCl₆ octahedra and an intergrowth layer consisting of PbCl₂ units, wherein the organic components are firmly anchored to the intergrowth layer via Pb─O bonds, thereby enhancing the crystal stability and effectively suppressing ion migration, as evidenced by high ion migration activation energy (1.64 eV) and extremely low dark current drift (2.86 × 10 A cm V s). X-ray devices based on the ultra-stable heterostructure single crystal demonstrate an extraordinary sensitivity of 8453.3 µC Gy cm (at 40 V), ultra-low detection limit of 5.2 nGy s and superior air stability (≈1 year). Such values make it one of the most outstanding candidates for high-performance X-ray detection. This work promotes the development of heterostructure single crystals optoelectronic applications.
异质结构单晶由于其独特的性质以及在新型光电器件应用方面的潜力，已成为一种重要的功能材料体系。特别是，它们独特的结构特征为抑制离子迁移提供了广阔前景，这对于X射线检测极为有利。在此，通过将环己基甲胺阳离子逐步修饰为4-氨甲基四氢吡喃阳离子，成功获得了一种层状异质结构单晶(PbCl)(4-氨甲基四氢吡喃)PbCl。它由两个不同的无机骨架组成，即由PbCl₆八面体构建的钙钛矿层和由PbCl₂单元组成的共生层，其中有机成分通过Pb─O键牢固地锚定在共生层上，从而提高了晶体稳定性并有效抑制了离子迁移，高离子迁移活化能(1.64 eV)和极低的暗电流漂移(2.86×10 A cm V s)证明了这一点。基于这种超稳定异质结构单晶的X射线器件表现出8453.3 µC Gy cm(在40 V时)的非凡灵敏度、5.2 nGy s的超低检测限和出色的空气稳定性(约1年)。这些数值使其成为高性能X射线检测最杰出的候选材料之一。这项工作推动了异质结构单晶光电器件应用的发展。
