Highly‐Anisotropic Dion–Jacobson Hybrid Perovskite by Tailoring Diamine into CsPbBr<sub>3</sub> for Polarization‐Sensitive Photodetection
Tao Yang, Yaobin Li, Shiguo Han, Zhiyun Xu, Yi Liu, Xinyuan Zhang, Xitao Liu, Bing Teng, Junhua Luo, Zhihua Sun
Abstract
Abstract 2D materials with inherent attributes of structural anisotropy have been well applied in the field of polarization‐sensitive photodetection. However, to explore new 2D members with strong polarized‐light responses still remains a challenge. Herein, by alloying diamine molecule into the 3D prototype of CsPbBr 3 , a new Dion–Jacobson (DJ) type 2D perovskite of (HDA)CsPb 2 Br 7 ( 1 , where HDA 2+ is 1,6‐hexamethylenediammonium), containing both inorganic Cs metal and organic cations is designed. The natural anisotropy characteristics of 1 are solidly elucidated by analyzing crystal structure, electric conductivity, and optical properties. Strikingly, distinct polarization‐sensitive responses are observed in 1 , owing to its strong anisotropy of optical absorption (the ratio of α c / α b ≈ 2.2). Consequently, crystal‐based detectors of 1 exhibit fascinating photo‐activities to polarized‐light, including high detectivity (1.5 × 10 9 Jones), large dichroism ratio ( I ph c / I ph b ≈ 1.6) and fast responding rate (200 µs). All these polarization‐sensitive performances along with intriguing phase stability make 1 a potential candidate for polarized‐light detection. This work paves a pathway toward new functionalities of DJ‐type 2D hybrid perovskites for their future optoelectronic device applications.