Ultra-Tough and Stable Leather-Derived Gel Wearable Sensor: Enabling Multimodal Monitoring of Human Motion Signals and Distress Signal Transmission.

In extreme scenarios such as emergency rescue operations, conventional hydrogel sensors face significant challenges in achieving real-time distress signal transmission due to their mechanical brittleness and stringent signal transmission requirements. This study introduced a multifunctional integrated carbon quantum dots (CCQDs)-empowered ultra-tough and stable leather-based gel multimodal wearable sensor (SMT-TL), aiming to achieve long-term stable distress signal transmission. SMT-TL utilized zeolite-tanned sheep leather (SMT-L) as a rigid substrate, with flexible polyacrylic acid (PAA) densely filling the gaps of collagen fibers within SMT-L and enhancing hydrogen bond interactions. This resulted in the fabrication of an ultra-tough, ultra-stretchable, multifunctional integrated, and transparent "rigid-flexible combination" SMT-TL. It retained over 70% of the breaking strength (>13.5 MPa) of original SMT-L, while achieving an elongation exceeding 590.0%, a toughness greater than 63.64 MJ/m, and maintaining good transparency (a transmittance greater than 78.0% at 550 nm). The multifunctional integrated CCQDs enhanced and endowed SMT-TL with conductivity and antibacterial properties, while the glycerol-water binary solvent system ensured its anti-freezing and moisture-retention capabilities. Notably, SMT-TL not only enabled real-time monitoring of human motion signals but also successfully achieved stable transmission of distress signals. We believe that this study offers a new sensing material for extreme emergency communication, advancing intelligent integration of leather-based wearable sensors with broad applications.