Highly Sensitive and Ultrafast Responding Array Photodetector Based on a Newly Tailored 2D Lead Iodide Perovskite Crystal

2D organic-inorganic hybrid perovskites are emerging as the promising alternatives in photodetection, due to their unique merits stemming from intrinsic quantum-confined structures. Despite great ongoing effects, highly sensitive and ultrafast responding photodetectors of 2D hybrid perovskites remain a huge blank. Here, the first nanosecond-responsive array photodetector based on 2D perovskite crystals of (PA)(2)(G)Pb2I7 (where PA = n-pentylaminium and G = guanidinium) is fabricated, which features a newly tailored bilayer motif with large-size G cation as perovskiter inside the distorted PbI3 perovskite framework. This motif creates a new branch of the intriguing 2D hybrid perovskite family. Strikingly, both high photodetectivities (6.3 x 10(12) Jones) and responsivities (approximate to 47 A W-1), as well as low dark current (approximate to 2.4 x 10(-11) A), are achieved in this array photodetector. Further, its ultrafast response time (tau) of 3.1 ns is one of the record-fast merits for 2D hybrid perovskites. Such attributes originate from its strong in-plane photoresponse related to perovskite network and low dark current inhibited by the hopping barriers of insulating PA bilayers. All these characteristics make (PA)(2)(G)Pb2I7 a promising candidate for photodetection, and pave the way to explore new 2D hybrid perovskite candidates for future high-performance optoelectronic devices.