Self-healing flexible and strong hydrogel nanocomposites based on polyaniline for supercapacitors

Flexible all-solid-state supercapacitor has been widely used in various portable and wearable electronics devices. Flexible electrode is an important part in flexible supercapacitors. In this work, we fabricate a self-healing polyaniline–poly (vinyl alcohol) (PANI–PVA) composite hydrogels with excellent mechanical characters, brilliant rate capability, and good electrochemical performance. The synergistic effects offered by flexibility of PVA macromolecular chains, high electrical conductivity of carbon nanotubes, reversible hydrogen bonding between phytic acid and PVA, and pseudocapacitance of PANI give PANI–PVA hydrogels the stated advantages. Based on PANI–PVA composite hydrogel, a flexible all-solid-state supercapacitor was fabricated to further investigate the electrochemical performance and self-healing properties. The fabricated supercapacitor not only delivers an outstanding cycle life (97.5% capacitance retention after 1000 galvanostatic charge–discharge cycles), but also displays good self-healing properties (capacitance retention of about 95% after 10 healing cycles). This study can significantly contribute to the development and manufacture of conductive composites and self-healing flexible energy storage devices.