Ultrafast Fabrication of Lignin-Encapsulated Silica Nanoparticles Reinforced Conductive Hydrogels with High Elasticity and Self-Adhesion for Strain Sensors

作者：Haonan Zhao, Sanwei Hao, Qingjin Fu, Xinrui Zhang, Lei Meng, Feng Xu, Jun Yang · 发表于：Chemistry of Materials · 年份：2022 · DOI：10.1021/acs.chemmater.2c00934 · 被引用次数：205 · 研究领域：Advanced Sensor and Energy Harvesting Materials、Conducting polymers and applications、Tactile and Sensory Interactions

Conductive hydrogels are receiving considerable attention because of their important applications, such as flexible wearable electronic, human-machine interfaces, and smart/soft robotics. However, the insufficient mechanical performance and inferior adhesive capability severely hinder the potential applications in such an emerging field. Herein, a highly elastic conductive hydrogel that integrated mechanical robustness, self-adhesiveness, UV-filtering, and stable electrical performance was achieved by the synergistic effect of sulfonated lignin-coated silica nanoparticles (LSNs), polyacrylamide (PAM) chains, and ferric ions (Fe 3+ ). In detail, the dynamic redox reaction was constructed between the catechol groups of LSNs and Fe 3+, which could promote the rapid gelation of the acrylamide (AM) monomers in 60 s. The optimized conductive hydrogels containing 1.5 wt % LSNs as the dynamic junction points exhibited the excellent elasticity (<15% hysteresis ratio), high stretchability (∼1100% elongation), and improved mechanical robustness (tensile and compressive strength of ∼180 kPa and ∼480 kPa). Notably, the abundant catechol groups of LSNs endowed the conductive hydrogels with the long-lasting and robust self-adhesion, enabling seamless adhesion to the human skin. Meanwhile, the catechol groups also provided an exceptional UV-blocking capability (∼95.1%) for the conductive hydrogels. The combined advantages of the conductive hydrogels were manifested in flexible sensors for th...