A novel bone-inspired fatigue-resistant hydrogel with excellent mechanical and piezoresistive properties was developed, and it exhibited great potential as a load and strain sensor for underwater robotics and daily monitoring. The hydrogel was created by using the high edge density and aspect ratio of graphene nanosheet-embedded carbon (GNEC) nanomaterials to form a three-dimensional conductive network and prevent the expansion of microcracks in the hydrogel system. Multiscale progressive enhancement of the organic hydrogels (micrometer scale) was realized with inorganic graphene nanosheets (nanometer scale). The graphene nanocrystals inside the GNEC film exhibited good electron transport properties, and the increased distances between the graphene nanocrystals inside the GNEC film caused by external forces increased the resistance, so the hydrogel was highly sensitive and suitable for connection to a loop for sensing applications. The hydrogels obtained in this work exhibited excellent mechanical properties, such as tensile properties (strain up to 1685%) and strengths (stresses up to 171 kPa), that make them suitable for use as elastic retraction devices in robotics and provide high sensitivities (150 ms) for daily human monitoring.
Despite gel electrolytes' high ionic conductivity and appreciable mechanical softness making them promising candidates for flexible electronic devices (FEDs), preparing gel electrolytes which seamlessly interface with electrodes is still challenging, especially via rapid gelation. Inspired by cartilage, a mechanically interlocked and hydrogen bonded electrolyte–electrode interface (MHEEI) generated using an ultrafast gelation process via in situ interfacial polymerization of gelatin macromolecules and acrylamide monomers hybrid fluid is reported. A nanoporous carbon (NC) electrode favorable for polymer matrix embedding is employed to lock into the in situ gel electrolyte through a mechanical interlocking structure. Polyacrylamide chains inside the nanoporous electrode are strongly connected with gelatin chains via intra-intermolecular hydrogen bond interactions. Their synergy simultaneously imparts low contact resistance (1 Ω), high ionic conductivity (55.9 mS cm−1) and interfacial toughness of 16 J m−2 at MHEEI, which is 6.4 times greater than that obtained by a physical stacking approach. The NC electrode with MHEEI thus exhibits a specific capacitance of 336 F g−1 (at 8 A g−1), about 12 times greater than that of the electrode with MEEI. Additionally, an interrupted electronic circuit is instantly restored via ultrafast construction of interlocking layers. This concept can be demonstrated in other gel systems, providing generalized design principles for the ultrafast construction of interlocking structures for FEDs.
危险品化学品经营许可证（带存储）