Novel stretchable fiber-shaped fluidic nanogenerators fabricated from carbonized lignin/thermoplastic polyurethane

Harvesting energy from water flow using fiber-shaped fluidic nanogenerators (FFNGs) based on liquid-solid contact electrification has practical significance. Challenges remain in the fabrication of conformal FFNGs with favorable durability and a large strain range. Herein, a robust, flexible, and stretchable FFNG is fabricated using carbonized lignin and thermoplastic polyurethane via wet-spun approach. A maximum output direct current voltage of 420 mV is generated when the saline solution flows over a 6-cm-long FFNG. The output voltage of the FFNG shows excellent stability and repeatability in multiple cyclic tensile tests . Furthermore, the excellent mechanical properties and high stretchability of FFNG enable it to be woven into fabric, proving its tremendous potential for use in conformal electronics. The robust FFNG can also act as a self-powered wave sensor, which provides basic information on the wave conditions.