Perovskite Granular Wire Photodetectors with Ultrahigh Photodetectivity

Abstract Control over the morphology and crystallinity of metal halide perovskite materials is of key importance to enable high‐performance optoelectronics. Here, a simple yet effective template‐free self‐assembly synthesis of perovskite granular wires with ultrahigh photodetectivity (3.17 × 1015 Jones) is reported. The 1D self‐assembly of perovskite grains is driven by differences in the surface interaction energies of the granular facets. The superb photodetecting performance originates from extremely low dark current engendered by energetic barriers featuring unique band‐edge modulation along the long axis of wire. Flexible photodetector arrays, fabricated by selectively placing perovskite granular wires onto pre‐patterned electrode arrays on a transparent polymer substrate, show independently addressable photonic signal mapping with remarkably high detectivity, photoconductive gain, …