▎ 摘　　要

NOVELTY - Preparing polyvinyl alcohol/quaternary ammonium chitosan (PVA/HACC) piezoelectric hydrogel involves adding quaternary ammonium chitosan (HACC) into water until HACC is completely dissolved to obtain a transparent HACC solution, and adding polyvinyl alcohol (PVA) to HACC solution until the PVA is completely dissolved to obtain PVA/HACC solution. Liquid metal (LM) is added into graphene oxide (GO) dispersion liquid, sonicated, added hydrochloric acid dropwise for reduction to obtain black precipitate, centrifugally cleaned and dried to obtain a black solid. The black solid is mixed with the dispersant solution and ulrasonicated to obtain LM/rGO conductive dispersion. The obtained dispersion is added into the PVA/HACC solution to obtain black precursor solution by ultrasonication, placed in a -20°C environment for freezing, and then placed at room temperature . The freezing and room temperature treatments are repeated for at least 3 times to finally obtain PVA/HACC piezoelectric hydrogel. USE - Method for preparing PVA/HACC piezoelectric hydrogel used as piezoelectric piezoresistive sensor in wearable electronic devices (all claimed). ADVANTAGE - The method is simple, cost effective, and the hydrogel prepared by physical crosslinking also has piezoelectric and piezoresistive sensing properties.