An anti-freezing and conductive glycerol-Mo-based organohydrogel electrolyte for flexible supercapacitor

By partially substituting water molecules in polymer hydrogel electrolytes with organic solvents, the-low temperature tolerance of supercapacitors can be significantly improved. However, the low conductivity resulting from the organic solvents inevitably influences the energy storage behavior of the supercapacitor. To address this issue, a new strategy is employed by embedding glycerin (Gly)-Mo into both the electrolyte and electrode materials, resulting in a supercapacitor that exhibits outstanding conductivity and resistance to subzero temperatures. The introduction of Gly-Mo enhances the mechanical properties and conductivity of hydrogel under freezing conditions. The in situ growth of an electrode containing Gly-Mo lowers the interface resistance between the electrode and electrolyte. When the temperature decreases from room temperature to − 40 °C, the supercapacitor retains 63.36% of its specific capacitance. Furthermore, the flexible supercapacitor is capable of withstanding punching damage, maintaining a specific capacitance of 140.75 mF cm −2 at 1 mA cm −2 with 300 holes cm −2 . The supercapacitor also exhibits remarkable capacitance retention after being bent at a 90° angle for 400 cycles.