Anti-Freezing Fiber-Shaped Iontronic Synapses With Ultralow Energy Consumption and High Rectification.

Fiber-shaped iontronic synapses (FEISs) are emerging as promising building blocks for next-generation wearable neuromorphic computing due to their ability to emulate biological signal transmission and plasticity. However, their practical application remains limited by poor environmental adaptability, high energy consumption, and inadequate rectification behavior. Herein, we report a FEIS with anti‑freezing capability that simultaneously achieves ultralow energy consumption and a high rectification ratio. The FEIS is constructed by directly assembling tetrachlorobenzoquinone and zinc hexacyanoferrate onto carbon nanotube fibers via π-π stacking, combined with a sucrose-modified polyacrylamide hydrogel electrolyte that inhibits ice formation through hydrogen bond regulation. Our FEIS exhibits stable synaptic operation at -20°C, with an ultralow energy consumption of 17 fJ per synaptic event, and a high rectification ratio of 17.9, enabled by asymmetric Faradaic reactions and ionic relaxation kinetics. These characteristics enable the FEIS to achieve robust unidirectional information transmission and stable synaptic operation, even under cryogenic conditions. Furthermore, the FEIS demonstrates reliable operation in ionic logic circuits and robotic control systems, achieving 95.2%-digit recognition accuracy at -20°C. This work expands the operational boundaries of flexible iontronic neuromorphic devices for applications in extreme environments.