Centimeter-Scale 2d Perovskite (Pea)(2)Pbbr4 Single Crystal Plates Grown By A Seeded Solution Method For Photodetectors

Large-sized single-crystal two-dimensional (2D) perovskites are highly desirable owing to their fundamental properties and intriguing ability to boost devices. Herein, 2-phenylethylammonium lead bromide [(PEA) 2PbBr4] single crystals, which are a violet-light-emitting 2D perovskite material, with typical lateral sizes of about one centimeter were successfully grown using a seeded solution method. The singlecrystal plates showed a well-defined shape (rectangle or hexagon), a natural thickness (300-500 mm) similar to that of conventional silicon and InP wafers, a large aspect ratio of 20, and a smooth surface (root mean square, 0.7 nm). We integrated these single crystal plates into an ultraviolet photodetector, achieving a low dark current of 10 13 A and an efficient photoresponse (on/off ratio, 103). This experiment could easily be extended to grow freestanding 2D perovskite single crystals on a wafer scale for practical integrated optoelectronics.