Large‐Area, Semitransparent, and Flexible All‐Polymer Photodetectors

Abstract Photodetectors, converting optical signals from specific wavelengths to electrical signals, have many applications on photoimaging, optical communication, and environmental monitoring. Solution‐processed organic photodetectors (OPDs) based on organic materials emerge promise especially for wearable electronics and smart buildings. In this work, new all‐polymer photodetectors (all‐PPDs) are developed based on bulk‐heterojunction active layers which incorporate a donor polymer and an acceptor polymer. The inverted all‐PPDs exhibit outstanding external quantum efficiency over 70%, low dark current density ( J d ) of 1.1 × 10 −8 A cm −2 , and high detectivity ( D *) over 3.0 × 10 12 Jones with planar response over the entire visible range. It is one of the best‐performing all‐PPDs reported so far and is also comparable with many organic and inorganic photodetectors. By using lamination technique, large‐area, semitransparent, flexible, and “fully” polymeric photodetectors are successfully fabricated for the first time, with D * over 10 11 Jones for double‐side light detection. The results highlight the great potential for producing high‐performance all‐PPDs by taking advantages of various device architecture and solution‐processing techniques.