3D/2D Perovskite Single Crystals Heterojunction for Suppressed Ions Migration in Hard X-Ray Detection
3D/2D Perovskite Single Crystals Heterojunction for Suppressed Ions Migration in Hard X-Ray Detection
复制标题
DOI：
10.1002/adfm.202104880
复制
发表时间：
2021-09-08
影响因子：
19
通讯作者：
Yang, Bai
中科院分区：
文献类型：
--
作者：
He, Yuhong;Pan, Wanting;Yang, Bai
卤化物钙钛矿根据其成分表现出不同的特性。然而，将所需的特性集成到一种材料中仍然具有挑战性。本文报道了一种简便的溶液处理外延生长方法，可在 3D 钙钛矿单晶顶部生长 2D 钙钛矿单晶，该方法可以钝化表面缺陷，从而提高器件性能。短甲脒(FA(+))离子被长有机阳离子取代，可以充分排列并覆盖单晶表面，防止离子迁移或短FA(+)离子挥发。通过控制生长时间可以微调外延层的厚度。单晶异质结的缺陷密度仅为3.18×10(9)cm(-3)，载流子迁移率为80.43cm(2)V-1s(-1)，大于对照3D钙钛矿单晶。该研究首次实现了大面积3D/2D钙钛矿单晶异质结，抑制了离子迁移，在硬X射线检测应用中表现出先进的性能。该策略还提供了一种通过溶液工艺生长大面积二维钙钛矿单晶的方法。
Halide perovskites exhibit diverse properties depending on their compositions. However, integrating desired properties into one material is still challenging. Here, a facile solution-processed epitaxial growth method to grow 2D perovskite single crystal on top of 3D perovskite single crystal, which can passivate the surface defects for improved device performance is reported. Short formamidine (FA(+)) ions are replaced by long organic cations, which can fully align and cover the single crystal surface to prevent the ions migration or short FA(+) ions volatilization. The thickness of epitaxial layer can be finely adjusted by controlling the growth time. The defect density of single crystals heterojunction is only 3.18 x 10(9) cm(-3), and the carrier mobility is 80.43 cm(2) V-1 s(-1), which is greater than that of the control 3D perovskite single crystal. This study for the first time realized large area 3D/2D perovskite single crystals heterojunction, which suppressed ions migration and exhibited advanced performance in hard X-rays detection applications. This strategy also provides a way to grow large area 2D perovskite single crystal from solution processes.