Continuously fabricated nano/micro aligned fiber based waterproof and breathable fabric triboelectric nanogenerators for self-powered sensing systems

The electronic textile has been evolving into a multifunctional flexible electronics platform. However, due to processing methods, e.g., coating, the fabric is endowed with electronic functionality while weakening its original performances. Thus, there is still a long way for electronic fabrics. Here, a nano/micro core-sheath yarn-based waterproof and breathable fabric triboelectric nanogenerator (CSYF TENG) is continuously fabricated for energy harvesting, self-powered humidity, and subtle force sensing systems. Different from coated yarns, our uniaxially aligned CSYs with ordered nanofibers tightly wrapping around the conductive fibers are manufactured via a one-step conjugate electrospinning technique. Owing to the hierarchical structure and tremendous specific surface areas, CSYF TENGs exhibit unparalleled electrical outputs with excellent durability and biomechanical pressure sensitivity, demonstrating superior comfortability, i.e., waterproof property, breathability, and flexibility, without sacrificing fabric's original properties. Furthermore, based on the micro/nano radial expansion fiber-based fabric architecture, the excellent humidity management properties are manifested, resulting in a fast response (8 s)/recovery of electrical outputs toward humidity, making CSYF TENG an ideal self-powered humidity sensor. Besides, this TENG can be used as a bioenergy harvester, a self-powered tiny force sensor, and a fabric-based e-skin with excellent machine-washable and abrasion resistance properties. This work highlights the numerous applications of CSYs for wearable TENGs and self-powered electronic textiles.