Organic Bulk‐Heterojunction‐Integrated Flexible Perovskite Photodetection Arrays for High‐Speed Broadband Optical Communication

Abstract The demand for self‐powered, broadband photodetectors is rising in fields like artificial intelligence, health monitoring, and optical communications. However, conventional perovskite photodetectors face limited visible absorption and poor ambient stability. Here, we report a high‐performance integrated photodetector combining a perovskite (Cs n.15 FA n.85 PbI 3 ) absorber with an organic bulk‐heterojunction (BHJ) structure for broadband photon harvesting up to 1000 nm. The device achieves a peak external quantum efficiency (EQE) of 84% in the visible range (400–700 nm) and 63% in the near‐infrared (NIR, 700–1000 nm). Benefiting from optimized energy band alignment, the photodetector exhibits a self‐powered responsivity of 0.3 A W −1 and a fast response time of 29 µs, with a linear dynamic range (LDR) of 122 dB under 900 nm NIR illumination. The BHJ organic layer suppresses the dark current (J D ) to 6.9 × 10 −11 A cm −2 and noise current (i n ) to 10‐14 A Hz −1/2 , yielding a specific detectivity (D*) of 10 12 Jones. The polymeric BHJ also enhances flexibility, enabling a reliable 25‐pixel array for uniform NIR imaging. In optical communication, the device achieves a low bit error rate with data rates of 90 kbps (λ = 665 nm) and 140 kbps (λ = 904 nm). This work establishes the perovskite/BHJ detector as a promising platform for flexible, high‐speed optoelectronics.