Confinement Effect Enhanced Ultra-Low Temperature Tolerance in Organo-Hydrogels with High Electrical Conductivities for Soft Electronics

Conducting organo-hydrogels is promising for soft electronics applications. However, conventional organo-hydrogels typically exhibit low electrical conductivity (<5 S cm⁻¹) at subzero temperatures (←20 °C), severely limiting their utility in low-temperature soft electronics. In this work, a PEDOT:PSS-based all-polymer organo-hydrogel are developed with ultralow-temperature tolerance down to −90 °C and record high electrical conductivity up to 698.3 ± 37.3 S cm⁻¹. The high electrical conductivity is due to a developed preparation method and the ultra-low temperature tolerance property is attributed to the suppression of the coagulation of the organo-hydrogel with alcohols as well as the confinement effects of the porous structure existing in the hydrogel films. The obtained highly conductive organo-hydrogel films exhibit high performance in thermoelectrics, electromagnetic interference shielding, and stretchable strain sensors in subzero temperatures. A thermal driven grabber has been fabricated to demonstrate the good flexibility, the good strain–stress property, and the good Joule-heating ability of the conducting organo-hydrogels at low temperatures. This work extends the operational temperature limits of organo-hydrogel electronics to extreme cold environments (>−90 °C).