Multifunctional Skin Collagen Fiber Scaffold-Based Composite Flexible Sensing Materials for Motion Monitoring and Energy Harvesting

The proliferation of sustainable intelligent wearable devices for healthcare monitoring and human–machine interfaces has intensified the requirements for flexible sensing materials. Conventional flexible sensing materials suffer from inadequate mechanical robustness, functional singularity, and unsatisfactory conductivity due to inherent material design constraints. Herein, we developed a skin collagen fiber scaffold-based composite flexible sensing material through the hierarchical integration of natural goatskin's intact hierarchical collagen fiber architecture with synthetic polymer networks via a "top-down" fabrication strategy. Sequential infiltration and in situ polymerization of acrylamide/acrylic acid monomers within the collagen fiber matrix yielded a skin-derived multifunctional composite flexible sensing material (named S-MFCP) featuring three-dimensional polymer-encapsulated collagen fibers and multiscale hydrogen-bonding networks, achieving exceptional mechanical performance (4.8 MPa ultimate tensile strength, 300% fracture strain). Strategic incorporation of Fe3+ ions, curcumin-derived carbon quantum dots, and 1,3-propanediol imparted synergistic ultrahigh electrical conductivity (8.8 S/m at −24 °C), broad-spectrum antimicrobial efficacy (12.6 cm2 inhibition zone against S. aureus), and cryogenic tolerance (maintaining 95% of its original toughness after freezing for 24 h at −24 °C). The S-MFCP demonstrated precise human motion tracking through stable strain-responsive signals and served as a high-efficiency triboelectric nanogenerator for the harvesting of biomechanical energy, self-powered sensing, and real-time kinematic monitoring. This biohybrid engineering paradigm leveraging natural skin collagen fiber scaffolds establishes a material platform for multifunctional wearable electronics, bridging ecological sustainability with advanced electromechanical functionality.