Antifreeze high stretch ion-conducting hydrogels and their application in flexible devices

Hydrogel shows breaking stress 0.36 MPa, elongation 1923%, conductivity 3.63 S m −1 (room temp) and 1.07 S m −1 at −18 °C, indicating anti-freezing. Supercapacitor based on it achieves specific capacitance 70.5 F g −1 at 1 A g −1 (0–0.8 V).