Flexible and Stable Ternary Organic Photodetector for Broadband Visible–NIR Applications in High‐Fidelity Imaging and Optical Communication

Abstract Organic photodetectors (OPD)have emerged as promising candidates with broadband photodetection from the visible to the near‐infrared (NIR) region. However, challenges like limited response speed and environmental instability remain. Herein, we present a vis–NIR responsive OPD based on PTB7‐Th:BTP‐4F:COTIC‐4F ternary organic system, achieving broadband detection covering up to 1200 nm. This OPD demonstrates an impressive response time of 43/64 ns, with outstanding durability, maintaining stable performance for bending and water immersion, showing resilience under both mechanical and environmental stresses. Transient absorption spectra ( TAS ) reveal ultrafast charge transfer processes, facilitating the rapid response speed. Moreover, we successfully demonstrated its potential in high‐fidelity imaging and fast optical communication. This work demonstrates a stable, ultrafast OPD with practical vis–NIR applications, paving the way for future advancements in flexible photonic technologies.