Effect of the Geometrical Structure on the Superhydrophobicity and Self-Cleaning Properties of Plasma-Treated Polyvinylidene Fluoride Fabrics.

The purpose of this study is to develop superhydrophobic polyvinylidene fluoride (PVDF) fabrics to increase their water repellency and self-cleaning properties and to investigate the effects of the inherent fabric roughness on these properties. A PVDF fabric, composed entirely of electrospun PVDF filament yarns, and two PVDF/polyester (PET) fabrics with different weave densities are used. After treatment with O plasma for 12 min and CF plasma for 4 min, superhydrophobicity is achieved in all fabrics, resulting in an increase in water repellency and self-cleaning efficiency. The PVDF fabric with the lowest shedding angle exhibits the most pronounced droplet rebound behavior and the highest self-cleaning efficiency. Increases in surface inclination angle and droplet volume and a decrease in the drop fall height all contribute to conditions more favorable for water droplet repellency. The self-cleaning efficiencies of the plasma-treated PVDF fabric and high-density PVDF/PET fabric are higher for hydrophilic dust, in contrast to those of the untreated ones. The findings of this study are expected to enable the design of weaving or nano-structuring conditions that enhance the water repellency and self-cleaning properties of PVDF fabrics, for the development of stable energy-harvesting smart textiles.