Ultra‐Sensitive Optoelectronics Enabled by Atomically Tailored Interfaces Engineering for Advanced Perceptual Imaging

Abstract Ultra‐weak light detection represents a critical enabling technology for next‐generation imaging, remote monitoring, and autonomous systems, where efficient charge transfer is essential to achieve ultralow detection thresholds. Herein, an interfacial lattice‐distortion engineering strategy is proposed by selectively substituting phenylethyl ammonium (PEA) cations with 4‐chlorophenylethylammonium (Cl‐PEA) at perovskite heterointerfaces. This substitution induces beneficial octahedral distortions, boosting hole transport efficiency in few‐layer 2D perovskites by 26%. When integrated with MoS 2 /WSe 2 heterostructures, the optimized van der Waals contact and enhanced energy‐level alignment yield a high‐performance photodetection, including a responsivity of 2.7 × 10 4 A/W, a detectivity up to 5.26 × 10 14 Jones, and an exceptionally low noise equivalent power of 0.42 fW Hz −1/2 . Notably, the device operates self‐powered at incident power densities as low as 0.54 µW cm −2 , enabling real‐time, on‐chip image processing even under dim‐light conditions. This functionality is further utilized for noise reduction in traffic‐light images prior to object detection with YOLOv11 network, establishing a direct bridge between device‐level photodetection and machine‐learning‐driven recognition. This interfacial lattice distortion engineering paradigm in van der Waals‐contacted 2D devices opens new avenues for designing ultrasensitive, low‐noise, and functionally integrated optoelectronic devices.