Solution‐Processed, Self‐Powered Broadband CH 3 NH 3 PbI 3 Photodetectors Driven by Asymmetric Electrodes

Abstract In general, the fabrication of high‐performance, self‐powered broadband photodetectors based on traditional semiconducting thin films is tedious and costly. Here, in this paper a high‐performance, solution‐processed, and self‐powered CH 3 NH 3 PbI 3 (MAPbI 3 ) nanocrystal based photodetector ITO/MAPbI 3 /Ag is presented, and it shows broadband photoresponse from the visible to the near‐infrared wavelength region. The pronounced enhanced performance of the photodetector is due to taking the advantage of the built‐in electric field induced by the work function difference of two electrodes. The optimized photodetector shows a responsivity of 4.9 and 1.42 A W −1 with a specific detectivity of 7.6 × 10 13 and 1.77 × 10 13 Jones under 19 µW cm −2 white light illumination and 26 µW cm −2 808 nm illumination at zero bias, respectively. Therefore, such a concept of simple device geometry and feasible technique will open up a new and promising avenue for the fabrication of self‐powered photodetectors and the development of imaging devices.