Simultaneous Superhydrophobic and Photo-catalytic Properties on Polyester Fabric: Prior in-situ Synthesis of Nano ZnO with Subsequent Fluorochemical-based Water Repellent Treatment

A combination of two significant requirements of low surface energy and roughness should be utilized to obtain the lotus effect on polyester fabric. In this research, ZnO nano-particles were first in-situ synthesized on the polyester fabric using zinc nitrate and NaOH to create nano-roughness as one requirement for producing a superhydrophobic surface. The ZnO pre-treated fabrics were then irradiated under sunlight for seven consecutive days to enhance the hydrophilicity. They were then treated with a fluorocarbon-based water repellent through the pad-dry-cure method to generate the surface with low energy. The produced fabric considered as a substrate manipulated the lotus topography. The superhydrophobic properties of treated fabrics were investigated through contact and sliding angles, spray, and water drop tests. The surface morphology was observed under SEM, and the presence and distribution of Zn and F elements were proved by EDX and mapping pictures. The self-cleaning behaviors were examined by discoloration of Methylene Blue as a stain under daylight irradiation. The influence of nano ZnO pre-treatment and then daylight irradiation was positively indicated on the fluoropolymer post-treatment that was provided a superhydrophobic fabric with sliding and contact angles of 8 and 157.3 °, respectively.