A Mechanically Durable Hydrogel Synapse

Abstract Stretchable artificial synapses that integrate neuromorphic functions and mechanical deformability have shown great promise in emerging fields. However, it is still challenging to develop an artificial synapse with intrinsic stretchability and resistance to physical damage, due to limitations in the development of stretchable electronic materials and the device principle for emulating synaptic functions in mechanically deformed and damaged conditions. Herein, an optically modulated conductivity switching property in a hydrogel material through a stimuli‐responsive supramolecular assembly process is achieved, which not only emulates biological synaptic functions, but also offers excellent adaptability to mechanical deformations and damages. The intrinsically stretchable hydrogel synapse exhibits a large stretchability up to 50% and can be operated properly under dynamic stretching conditions. Furthermore, the hydrogel synapse demonstrates remarkable tolerance to severe penetrating damage while maintaining reliable modulation of synaptic plasticity. As a proof of concept, an optically mediated feedback system operated by hydrogel synapses is showcased, which can regulate the logic feedback behavior of a robotic hand with associate learning capability. This work presents a novel chemical approach for designing mechanically durable artificial synapses, paving the way for the application of functional soft materials in neuromorphic devices and artificial intelligent systems.