Anti‐Freezing Self‐Adhesive Self‐Healing Degradable Touch Panel with Ultra‐Stretchable Performance Based on Transparent Triboelectric Nanogenerators

Abstract The development of next‐generation touch panels requires sensors that are highly sensitive, biocompatible, transparent, stretchable, self‐healing, and even anti‐freezing and self‐powered because the traditional touch panel based on stiff and brittle electrodes faces many challenges. Conductive hydrogels hold great promise as sensing materials for the new‐generation touch panel. However, most hydrogel‐based touch panels are developed based on single‐function gel materials with a lack of the anti‐freezing and self‐power capabilities. Herein, the authors demonstrate a multi‐functional surface‐capacitive touch panel based on a triboelectric nanogenerator with an instantaneous peak power density of 209 mW m −2 that uses zwitterionic network hydrogels as a highly transparent (98.1% transmittance), ultra‐stretchable ( > 11 500% strain), degradable, and flexible ionic conductor. The panel can be utilized as a human‐machine interactive interface with fast response, high resolution, low parasitic capacitance, functional recovery instantly upon damage, and without sacrificing its functionalities even in the high stretch state (1600% areal strain) and at the subzero environment ( <− 20 ° C). Epidermal touch panels are operated on arbitrary and complex surfaces, with outstanding input property demonstrated by writing, and playing computer games. Simultaneously, the multifunctional touch panel is degradable in phosphate buffered saline solution, and no pollution is caused.