Scalable coaxial wet-spinning of core-shell triboelectric fibers for self-powered smart fabrics

The development of wearable self-powered systems faces the daunting challenge of balancing high energy output, mechanical durability, and seamless integration with textiles. In this work, we presented an innovative core-shell composite fiber triboelectric nanogenerator (CSF-TENG) fabricated by a scalable coaxial wet-spinning strategy that synergistically integrated energy harvesting, environmental adaptation, and smart sensing. This fiber consisted of a graphene-bridged thermoplastic polyurethane (TPU) conductive core for efficient charge transfer and TiO₂-doped TPU triboelectric shell for simultaneously enhanced surface charge density and washability. CSF-TENG provided excellent output (open-circuit voltage of 130 V, short-circuit voltage of 3.9 μA, power density of 128.9 mW/m 2 ) meanwhile maintained breathability and elongation (>500 % strain). Woven into a fabric (WCSF-TENG), the composite material system functions as the self-powered human motion sensor, capturing subtle physiological signals, such as respiration and joint movements. Furthermore, WCSF-TENG also was used as an encrypted emergency communication platform for voice visualization and silent distress alerting via a wristband interface, on the basis of Morse code. This work demonstrated a viable composite material strategy which could be scalable to the next-generation smart textiles, effectively addressing the persistent trade-offs among performance, durability, and large-scale manufacturability in wearable electronics.