All-Fiber-Based Superhydrophobic Wearable Self-Powered Triboelectric Nanogenerators for Biomechanical and Droplet Energy Harvesting

The use of triboelectric nanogenerators to collect low-frequency mechanical energy has received widespread attention in recent years. Among these, single-electrode triboelectric nanogenerators have been studied for use as a power supply source for wearable electronic devices due to their simple and stable structure. The stability, hydrophobicity, and permeability under harsh environments are surely more pressing issues in the development and utilization of wearable devices. Herein, a superhydrophobic poly(vinylidene fluoride) nanofiber membrane with built-in polydopamine-coated carbon cloth electrode was prepared using electrostatic spinning technology and spraying process to develop an all-fiber-based single electrode triboelectric nanogenerator (F-TENG). The results show that the triboelectric nanogenerator has an open-circuit voltage of up to 270 V, a short-circuit current of up to 80 μA, and a maximum power density of about 1.79 W/m2. The F-TENG can quickly recover the electrical energy output after being affected by water droplets and has an excellent sensing performance with stability during repeated water spraying. It was suggested that the prepared F-TENG with good air permeability, flexibility, superhydrophobicity, and self-cleaning capability can be used to power IoT devices exposed to harsh environments, thus making it a self-powered energy source for wearable electronic devices.