Dynamically Cross‐Linked, Self‐Healable, and Stretchable All‐Hydrogel Supercapacitor with Extraordinary Energy Density and Real‐Time Pressure Sensing
Muchun Xu, Jiajun Zhu, Jiyang Xie, Yongyun Mao, Wanbiao Hu
Abstract
Abstract Wearable electronics with flexible, integrated, and self‐powered multi‐functions are becoming increasingly attractive, but their basic energy storage units are challenged in simultaneously high energy density, self‐healing, and real‐time sensing capability. To achieve this, a fully flexible and omni‐healable all‐hydrogel, that is dynamically crosslinked PVA@PANI hydrogel, is rationally designed and constructed via aniline/DMSO‐emulsion‐templated in situ freezing‐polymerization strategy. The PVA@PANI sheet, not only possesses a honeycombed porous conductive mesh configuration with superior flexibility that provides numerous channels for unimpeded ions/electron transport and maximizes the utilization efficiency of pseudocapacitive PANI, but also can conform to complicated body surface, enabling effective detection and discrimination of body movements. As a consequence, the fabricated flexible PVA@PANI sheet electrode demonstrates an unprecedented specific capacitance (936.8 F g −1 ) and the assembled symmetric flexible all‐solid‐state supercapacitor delivers an extraordinary energy density of 40.98 Wh kg −1 , outperforming the previously highest‐reported values of stretchable PVA@PANI hydrogel‐based supercapacitors. What is more, such a flexible supercapacitor electrode enables precisely monitoring the full‐range human activities in real‐time, and fulfilling a quick response and excellent self‐recovery. These outstanding flexible sensing and energy storage performances render this emerging PVA@PANI hydrogel highly promising for the next‐generation wearable self‐powered sensing electronics.