Violin String Inspired Core-Sheath Silk/Steel Yarns for Wearable Triboelectric Nanogenerator Applications

Triboelectric nanogenerator (TENG) has attracted considerable attention in wearable electronics and energy harvesting associated with human activities. Fiber/yarn electrodes are widely applied in the wearable TENG system, which remains a challenge to guarantee mechanical ductility and stable electrical functions during long-term use. Inspired by high quality violin strings core-sheath design, silk/stainless-steel integrated yarns (SSYs) are continuously produced by simple co-wrapping spinning technique, which shows excellent mechanical strength, flexibility, conductivity, weaveability and triboelectric function. The SSYs can be modified to achieve tunable surface morphology. Finally, TENG cables have been fabricated, which can be stretched up to 100% and reveal a fast responsiveness to the stretching extent (voltage output of about 0.2, 0.6, 1.8, 2.8 V at 13%, 25%, 38%, 50% stretching, respectively). The TENG cables integrated textiles can not only harvest the energy generated by body movement but can also work as a self-supplied motion detector.