A Bidirectional Photosensitive Multimodal PdSe2/MoS2 van der Waals Heterostructure Memristor Array for In-Sensor Neuromorphic Vision.

Optoelectronic van der Waals (vdW) memristors integrating photosensing, memory, and computing capabilities are promising for artificial vision but are limited by single photoresponse modes, low yields, and high device variability. Here, we demonstrate a 1-kb PdSe2/MoS2 van der Waals heterostructure (vdWH) optoelectronic memristor array with bidirectional photoresponse, unified sensing-memory-computing functions, high yield, and excellent uniformity. The vdWH interface induces competitive photogenerated carrier separation and recombination, enabling wavelength-dependent positive and negative photoresponses. A bilayer vdWH architecture confining filament formation paths, combined with a dual polymer transfer process for large-area intact vdW material transfer, achieves a high yield of over 90% and performance variations lower than 8%. Leveraging this bidirectional multimodal array, in-sensor image preprocessing, including denoising, recognition, and motion perception, is demonstrated, achieving up to 98.2% accuracy. This work establishes the bidirectional photosensitive multimodal PdSe2/MoS2 vdWH memristor array as a compact, high-performance hardware platform for next-generation intelligent artificial vision systems.