Robust Imaging through Light‐Scattering Barriers via Energetically Modulated Multispectral Organic Photodetectors

Abstract

Abstract Emerging technologies, such as biomedical imaging and autonomous driving, rely on low‐noise near infrared (NIR) photodetectors. Organic photodetectors (OPDs) offer tremendous potential for these applications because of their seamless integration and NIR photosensing capabilities; however, their high noise levels have constrained widespread commercialization. Herein, the study demonstrates a bulk heterojunction (BHJ) NIR OPD featuring an ultralow noise current of 2.18 fA, enabled by a newly synthesized electron‐blocking layer (EBL), ((2,7‐dicyano‐9 H ‐fluorene‐9,9‐diyl)bis(propane‐3,1‐diyl))bis(phosphonic acid) (3PAFCN). Through diverse energetic modulative design strategies, 3PAFCN enables the OPD to achieve homogenous surface properties, an elevated interfacial energy barrier, and optimized BHJ morphology, culminating in a notable specific detectivity of 2.50 × 10 14  cm Hz 0.5  W −1 at 808 nm illumination under white‐noise conditions. These EBL design principles are broadly applicable for various photoactive materials. Demonstrations in single‐pixel imaging highlight the exceptional clarity of the 3PAFCN‐based OPD in low‐light and foggy environments, underscoring the potential of OPD technology for advanced imaging applications.