A General Strategy for Ordered Carrier Transport of Quasi-2D and 3D Perovskite Films for Giant Self-Powered Photoresponse and Ultrahigh Stability.

Organic-inorganic hybrid perovskite materials have been focusing more attention in the field of self-powered photodetectors due to their superb photoelectric properties. However, a universal growth approach is required and challenging to realize vertically oriented growth and grain boundary fusion of 2D and 3D perovskite grains to promote ordered carrier transport, which determines superior photoresponse and high stability. Herein, a general thermal-pressed (TP) strategy is designed to solve the above issues, achieving uniaxial orientation and single-grain penetration along the film thickness direction. It constructs the efficient channel for ordered carrier transport between two electrodes. Combining of the improved crystal quality and lower trap-state density, the quasi-2D and 3D perovskite-based self-powered photodetector devices (with/without hole transport layer) all exhibit giant and stable photoresponse in a wide spectrum range and specific wavelength laser. For the MAPbI-based self-powered photodetectors, the largest R value is as high as 0.57 A W at 760 nm, which is larger than most reported results. Meanwhile, under laser illumination (532 nm), the FPEAMAPbI-based device exhibits a high responsivity (0.4 A W) value, which is one of the best results in 2DRP self-powered photodetectors. In addition, fast response, ultralow detection limit, and markedly improved humidity, optical and heat stabilities are clearly demonstrated for these TP-based devices.