High-Performance Friction Nanogenerators Based on Electrospun Poly(vinylidene fluoride) Loaded with Microbead Structures

Triboelectric nanogenerators (TENGs), which are capable of harvesting various forms of environmental mechanical energy or low-frequency mechanical energy from human movement and converting them into electrical energy, are some of the best choices to address the demand for distributed power sources. The performance of TENGs is significantly related to the materials and structures selected. Electrospinning nanofibers with a high specific surface area and porosity provide sites for friction layers to generate triboelectric charges. The excellent air permeability and stretchability are also more suitable for wearable electronics than inherently rigid conventional batteries. It has important implications for the development of self-powered wearable electronics. In this paper, poly(vinylidene fluoride) (PVDF)/polyamides 6 (PA6) all-electrospinning TENGs were prepared by single-needle spinning, and the output performance of the assembled TENGs was used as the foundation to investigate the electrospinning of PVDF and to derive the optimal spinning parameters. PVDF possesses a strong capacity to gain electrons, and the microbead structure of the PVDF nanofiber membrane (NFM) dramatically increases the effective contact area of the friction layer, which results in the excellent electrical output performance of the TENGs. The prepared TENGs are not only low-cost and simple to fabricate, with a maximum instantaneous power density of 583.31 mW/m2, which can be used to charge commercial capacitors or power small electronic devices, but also offer favorable durability and sensing capability in response to external stimuli. Additionally, the all-electrospinning structure provides a certain extent of comfort and holds great potential for application in wearable electronics for harvesting energy from the human body.