Hu Mengli, Zhang Yu, Meng Ning, Wang Wei, Lu Yao, Dong Jie, Zhao Suling, Qiao Bo, Song Dandan, Xu Zheng
Key Laboratory of Luminescence and Optical Information, Beijing Jiaotong University, Ministry of Education, Beijing 100044, China.
Institute of Optoelectronics Technology, Beijing Jiaotong University, Beijing 100044, China.
ACS Appl Mater Interfaces. 2023 Sep 13;15(36):42706-42716. doi: 10.1021/acsami.3c03110. Epub 2023 Aug 30.
Quasi-two-dimensional (quasi-2D) perovskites exhibit excellent performance when applied to light-emitting diodes (LEDs). However, quasi-2D perovskite films generally have nonuniform phases and irregular internal crystal structures, which degrade the device's performance. Here, we propose using a Dion-Jacobson (DJ)-type organic spacer to modulate the phase distribution of the Ruddlesden-Popper (RP) quasi-2D perovskite. A DJ-type organic spacer cation, 1.6-hexamethylenediamine (HDABr), was introduced into the perovskite as the second spacer cation with propylamine hydrobromide (PABr). As DJ-type and RP-type perovskites have similar spacings, RP-DJ style does not cause a chaotic crystalline structure; instead, it modulates the perovskite crystallization and narrows the phase distribution. In parallel, there is a substantial improvement in the maximum luminance, current efficiency, external quantum efficiency, and device stability of the quasi-2D perovskite LEDs. This work provides a novel concept for combining the organic spacer cations for quasi-2D perovskites.
准二维（quasi-2D）钙钛矿在应用于发光二极管（LED）时表现出优异的性能。然而，准二维钙钛矿薄膜通常具有不均匀的相和不规则的内部晶体结构，这会降低器件的性能。在此，我们提出使用狄翁-雅各布森（Dion-Jacobson，DJ）型有机间隔层来调节拉德勒斯登-波珀（Ruddlesden-Popper，RP）准二维钙钛矿的相分布。将DJ型有机间隔层阳离子1,6-己二胺氢溴酸盐（HDABr）作为第二种间隔层阳离子与丙胺氢溴酸盐（PABr）一起引入到钙钛矿中。由于DJ型和RP型钙钛矿具有相似的间距，RP-DJ结构不会导致晶体结构混乱；相反，它会调节钙钛矿的结晶并使相分布变窄。同时，准二维钙钛矿LED的最大亮度、电流效率、外量子效率和器件稳定性都有显著提高。这项工作为准二维钙钛矿的有机间隔层阳离子组合提供了一个新颖的概念。
