posted on 2023-11-17, 16:40authored byHuajie Wu, Zhijin Xu, Xin Dong, Lei Wang, Jing Liang, Tianqi Chen, Xiaoqi Li, Lina Li, Junhua Luo
Hybrid perovskites have great potential in photovoltaics
and photodetection.
Specially, two-dimensional (2D) hybrid perovskites have been discovered
to show distinctive applications in polarization-sensitive photodetection
due to their intrinsic anisotropy. Herein, we designed a new type
of 2D perovskite by introducing bifunctional alkylammonium as an organic
spacer, (β-Ala)4PbBr4 (1,
where β-Ala+ is 3-aminopropanoic), which has four
organic spacers in adjacent inorganic layers and adjacent organic
layers are linked by hydrogen bonding. The pioneering structure with
four organic spacers enables an intrinsic high strong anisotropy,
facilitating polarization-sensitive detection. The analysis of the
crystal structure and optical properties further elucidates the natural
anisotropic properties of 1. Strikingly, 1 has a strong optical dichroism (αc/αb ≈ 7.4 in 405 nm), and the polarization-sensitive detector
on single crystals of 1 exhibits a large polarization
ratio (Imax/Imin ≈ 2.0). This result highlights that the employment of bifunctional
cations is efficient to explore new type 2D perovskites for potentially
high-performance polarization-sensitive detection.