Stretchable, self-healable, and photodegradable supercapacitor based on a polyelectrolyte crosslinked via dynamic host-guest interaction

We report on the fabrication of a high performance multi-functional supercapacitor which is intrinsically stretchable, self-healable, and photodegradable. A repeatedly stretchable (500 times), photodegradable hydrogel that self-heals quickly at room temperature without any trigger is synthesized by crosslinking of azobenzeno-polyacrylamide (Azo-PAM) and water-soluble α-cyclodextrin polymer (α-CDP) via dynamic host-guest interaction. With the Azo-PAM/α-CDP/LiCl hydrogel as polyelectrolyte, the stretchable, self-healable, and photodegradable supercapacitor is fabricated. After complete bisection, the supercapacitor recovers its electrochemical performance by physical contact in air-ambient conditions and maintains its performance upon multiple cycles of self-healing at a single bisected location. It also maintains elastic performance even after repeated stretching and self-healing. Finally, the supercapacitor exhibits photodegrading performance, dissolving in water upon UV-irradiation after use. This work demonstrates the superior performance and high potential of our newly devised stretchable, self-healable, and photodegradable supercapacitor as a smart energy storage device for next-generation durable and eco-friendly wearable electronics.