Asymmetric CNT-doped Ionogel Heterostructure with Self-powered and Efficient Photoperception for Stretchable Neuromorphic Visual Skin

Neuromorphic visual skin (NVS), capable of self-powered, fast visual perception and complex elastic deformations, is highly desirable for cephalopod skin emulation but remains challenging. Here, we present an asymmetric carbon nanotube (CNT)-doped ionogel heterojunction with self-driven, efficient photoperception for stretchable NVS arrays. By leveraging the CNT-induced photothermoelectric effect in the heterostructure under light exposure, the junction exhibits zero power consumption, fast photoresponse (3.11 s), and retina-like photosynaptic behaviors within a multispectral range from 365 to 680 nm. By assembling the photoacceptor array into skin, its intrinsically soft elastomeric features endow the skin with outstanding stretchability of up to 50%. Utilizing the sensor nerve and convolutional neural network, the architecture achieves a 93.82% accuracy in image recognition. The asymmetric doping strategy in the ionogel offers an effective way for constructing self-powered soft photonic synapses toward skin-like embodied intelligence with photoreception capability.