Incorporating an Aromatic Diammonium To Assemble Bilayered Dion–Jacobson Perovskite Crystals for Weak Light Detection

Two-dimensional (2D) Dion–Jacobson (DJ) hybrid perovskites with exceptional stability and enhanced out-of-plane carrier transport are regarded as one of the competive candidates for constructing next-generation photodetectors. However, the studies of DJ hybrid perovskites on weak light detection remain scarce, and the devices based on them usually show relatively poor weak light detection ability, with a detection limit of around μW/cm2. Herein, a new DJ hybrid perovskite (3AMPY)(MA)Pb2Br7 [3AMPY is 3-(aminomethyl)pyridinium, and MA is methylammonium] with short interlayer spacing and more lattice rigidity is obtained. The devices based on (3AMPY)(MA)Pb2Br7 crystals exhibit an ultrahigh sensibility to weak light at 377 and 405 nm, with an extremely low detection limit of ∼70 nW/cm2. Moreover, the on/off ratios and detectivity of the devices can reach ∼103 and ∼1012 Jones at both 377 and 405 nm, respectively. This work highlights great potential of DJ hybrid perovskites toward weak light detection.