Bilayered Dion–Jacobson Hybrid Perovskite Bulk Single Crystals Constructed with Aromatic Diammonium for Ultraviolet–Visible–Near-Infrared Photodetection
Dongying Fu, Wenjuan Jia, Shichao Wu, Junli Chang, Zhuo Chen, Junhua Luo
Abstract
Two-dimensional (2D) Dion–Jacobson (DJ) hybrid perovskites (HPs) are widely used in the photodetection field due to their high stability and excellent carrier transport performance. However, current photodetectors based on DJ HPs can work only in the ultraviolet and visible wavebands, which limits their application in near-infrared (NIR) photodetection. Herein, for the first time, ultraviolet–visible–NIR photodetection is realized in the bulk single crystal of 2D bilayered DJ HP (3AMPY)(EA)Pb 2 Br 7 (3AMPY = 3-(aminomethyl)pyridinium, EA = ethylamine). Structurally, the introduction of aromatic diammonium makes (3AMPY)(EA)Pb 2 Br 7 have a shorter layer spacing (3.561 Å) and a more rigid structure. In addition, benefiting from the strong quantum and dielectric confinements of 2D HPs, (3AMPY)(EA)Pb 2 Br 7 shows an excellent two-photon absorption (TPA) coefficient of up to 61.1 cm/MW under the excitation of an 800 nm femtosecond laser. Notably, (3AMPY)(EA)Pb 2 Br 7 exhibits efficient photodetection from ultraviolet (377 nm) and visible (405 nm) to NIR (800 nm) wavebands, with on/off ratios of current higher than 10 3 .