Subnanowire-reinforced robust PVA hydrogel for multimodal wearable sensors enabling information transmission
摘要
Hydrogels, despite their potential in flexible electronics and wearable sensors, often suffer from inadequate mechanical robustness under sustained loading. This study aims to overcome this limitation by developing a novel nanocomposite hydrogel system through the integration of calcium-polyoxometalate sub-nanometer wires (Ca-POM SNWs) into a polyvinyl alcohol (PVA) matrix. Utilizing a H2O/ethylene glycol (EG) binary solvent, the hydrogel achieves uniform dispersion of Ca-POM SNWs, which enhances mechanical properties through dual reinforcement mechanisms: stress dissipation via polymer-mimetic flexibility and crystallinity improvement via hydrophobic ligand-induced chain alignment. The resulting PVA/Ca-POM hydrogel exhibits exceptional performance, including a 2.4-fold increase in fracture stress (0.85 MPa), 3.8-fold toughness enhancement (2.76 MJ m−3), and high ionic conductivity (3.6 S m−1). As a strain sensor, it achieves a gauge factor of 2.56 with rapid response, enabling precise detection of both large joint movements and subtle physiological vibrations. A prototype Morse code communication system further demonstrates its potential in assistive healthcare technologies, facilitating barrier-free, real-time communication between disabled patients and clinicians. This work highlights a breakthrough in inorganic-organic interface compatibility, offering a versatile platform for next-generation wearable technologies and extreme-environment applications. The innovative design principles and multifunctional performance underscore its significance in advancing soft material engineering.