Ultraflexible, Degradable Organic Synaptic Transistors Based on Natural Polysaccharides for Neuromorphic Applications

Abstract Ultraflexible and degradable organic synaptic transistors (OSTs) enable seamless integration with the human body and are capable of disintegrating after completing their specific functions, opening up remarkable new opportunities for “green” electronics in implantable neuromorphic systems, brain‐computer interfaces and wearable artificial intelligence systems. However, it is still an outstanding challenge to realize such synaptic transistors that simultaneously satisfy both ultra flexibility and degradability. The advancement of such electronics critically hinges on the development of ultraflexible and degradable gate dielectrics, which is the vital component to realize synaptic function of transistors. Here, for the first time, a self‐supporting natural dextran membrane is utilized as the gate dielectric to achieve an ultraflexible and degradable OST. The resultant device is only 309 nm thick, and can maintain stable synaptic behavior on various curved surfaces, even on a superfine capillary with the bending radius down to 0.15 mm. After the devices complete their functions, they can rapidly degrade in ambient water without any toxic byproducts, effectively reducing environmental pollution. More strikingly, proton conduction is confirmed to exist in neutral polysaccharides, and the protons originate from the self‐dissociation of water, which provides a meaningful guideline for future synaptic transistors based on neutral natural biomaterials.