Linfeng Cai

The dual‐band organic photodetectors (OPDs) detect incoming light selectively in two different bands. This work demonstrates a bias‐switchable dual‐band OPD, achieving a fast‐switching speed of over 1000 times per second and a −3 dB cutoff frequency of > 100 kHz for high‐speed optical communications in two distinct bands, e.g., near‐infrared (NIR) and visible light. Visible‐blind NIR detection with a high responsivity of 435 mA W^–1is realized for the OPDs operated under a small reverse bias of −1.0 V. NIR‐blind visible light detection with a responsivity of 325 mA W^–1is obtained for the OPDs operated under a low forward bias of 1.0 V. Dual‐channel NIR/visible optical communication technique has been demonstrated, providing an opportunity for a plethora of applications in information electronics and the Internet‐of‐Things.

Modification of the HTL helps to attain a high built-in potential (V₀) across the BHJ by suppressing the interfacial reaction at the HTL/BHJ interface. It is critical to retain a high and steady V₀ to obtain efficient and stable nonfullerene OSCs.

Photoresponsivity of the photonic-structured organo-lead triiodide (CH ₃ NH ₃ PbI ₃ ) perovskite photodetectors is less dependent on the angle of the incident light and has an enhanced omnidirectional photoresponse in the near infrared wavelength range.

Solution processable near infrared (NIR) photodetectors provide a promising alternative due to their low cost, flexible design, adaptability to various fabrications, and large area manufacturability, removing the limitations of traditional wafer-based inorganic semiconductor techniques. High performing NIR photodetectors offer attractive options for applications in visualizing NIR light, health and safety monitoring.