Self-powered photodetectors are indispensable for low-power optoelectronic systems such as edge sensing, optical communication, and machine vision. However, their development is severely hampered by interfacial defects that induce carrier leakage and nonradiative recombination. Here, we overcome this challenge by designing a WSe₂/GaSb van der Waals (vdW) heterojunction with favorable band alignment and a strong built-in electric field at the interface. The device delivers an ultralow dark current of ~2 pA at zero bias and a rectification ratio exceeding 10⁴, enabling zero-bias operation across 210-1000 nm. Under 880 nm illumination, it exhibits a responsivity of 331.5 mA W^-1, a specific detectivity of  Jones, an open-circuit voltage of 0.52 V, a maximum output power of 1.66 nW, and fast rise/fall times of 431/356 μs. Beyond device-level metrics, we demonstrate a closed “sensing-communication-computing” loop by realizing 8-bit ASCII optical communication and low-power near-infrared traffic sign recognition. Using U-Net reconstruction and YOLOv8n classification, the recognition accuracy is boosted from ~30% to ~80%, confirming its practical utility. This work provides an experimental and theoretical pathway toward next-generation self-powered, low-noise, intelligent vdW heterojunction photodetectors.

Conventional photodetectors dominated by a single physical effect are strictly constrained by the Shockley-Queisser limit, accompanied by intrinsic performance saturation, inadequate operational flexibility, and a complete absence of functions and secure functionalities. Here, we present large-area integrable Te/GaN heterostructure array devices fabricated from high-quality Te films via glancing-incidence physical vapor deposition. Benefiting from the intrinsic synergy between photovoltaic and photothermoelectric effects, these devices offer bias-free, position-programmable bipolar photoresponse. Under 365 nm illumination, the Te/GaN devices exhibit competitive figures of merit among similar devices, with positive/negative responsivity up to 308.4 mA/W and 54.5 mA/W, specific detectivity exceeding 1.09×10¹³ Jones and 7.52×10¹² Jones, respectively, at zero bias. By using illumination position and response polarity as dual physical keys, the developed wafer-scale 20×20-pixel Te/GaN heteroarrays successfully implement reconfigurable image processing and encrypted image transmission, demonstrating unprecedented intelligent and physically secure functionalities for next-generation optoelectronic chips. This work overcomes the performance bottlenecks and limited operational degrees of freedom in single-effect devices, and achieves reliable, scalable array applications without external components, establishing a universal paradigm for high-performance, intelligent and secure integrated optoelectronics systems.