Non-Planar A-D-A’-D-A Type Acceptors Enabling EQE over 5000% in Near-Infrared Organic Photomultiplying Photodetectors

Abstract

We report two A-D-A′-D-A type non-fullerene acceptors, CS-3 and CS-4, with twisted backbones and low crystallinity. Despite these structural drawbacks, CS-3-based photomultiplying organic photodetectors exhibit an external quantum efficiency (EQE) of 5600% at 800 nm and detectivity exceeding 1013 Jones. This work highlights the potential of non-planar molecular designs for achieving high-gain, broadband near-infrared detection beyond conventional structure–performance expectations.