Mixed-Dimensional Chiral COF-2D Molecular Crystal Heterojunctions for Neuromorphic Circular Polarization Vision.

Abstract

Emulating the biological visual system's ability to perceive and preprocess circularly polarized light (CPL) offers transformative opportunities for advanced imaging, quantum communication, and autonomous navigation. However, the implementation of such functionality in artificial systems demands the seamless integration of chiral selective sensing, efficient exciton dissociation, and neuromorphic processing capabilities, a combination that remains beyond the reach of current optoelectronic materials. Herein, a mixed-dimensional heterojunction architecture is presented, integrating a 3D chiral covalent organic framework (COF) with a 2D molecular crystal (2DMC), to overcome these limitations. By constructing a type-II band-aligned interface between a β-ketoenamine-linked TpPa-COF and an air-stable dithienothiophene-based 2DMC, the architecture enables directional, ultrafast interlayer charge transfer and efficient exciton dissociation at the interface. The resulting chiroptical synaptic transistor achieves a record polarization discrimination ratio (g_EPSC = 0.73) and exceptional photoresponsivity (7.7 × 10³ A W^-1), substantially surpassing existing organic CPL-sensitive detectors. Furthermore, when configured into a 3 × 3 convolutional kernel array, the device enables in-sensor noise reduction and feature extraction, elevating the classification accuracy of noisy images from 51.5% to 71.2% in the CIFAR-10 dataset. This work establishes an integrated material platform for CPL-driven neuromorphic vision, bridging chiral photonics with bioinspired computing.