Preparation of a high strength, rapid self-healing composite gel and its application in electrochemical capacitor

It is imperative to develop ideal self-healing material with intrinsic mechanical strength and mild self-healing conditions. Here, a rapid self-healing poly(vinyl alcohol) (PVA)/chitosan (CS) composite gel with multiple hydrogen bonds is designed. PVA/CS gel shows a particularly high strength of 0.266 MPa and can heal rapidly after completely broken. The self-healing performance can be ascribed to multiple hydrogen bonds provided by the P O/P–O⋯H groups of phytic acid. In particular, PVA/CS gel can be served as solid electrolyte . A flexible all-solid-state capacitor can be assembled based on the flexible polyaniline electrode and PVA/CS gel used as solid electrolyte. The capacitor exhibits a high specific capacitance of 390.6 mF/cm 2 and high capacitance retention ratio after hundreds of bends. Additionally, the PVA/CS gel can reconnect the broken capacitor with partial capacitance retention. This work can contribute to the design and fabrication of rapid self-healing gel and flexible all-solid-state capacitor.