Superhyrophobicity and antibacterial activity of ZnO nanoparticles coated cotton fabrics

The superhydrophobic and antibacterial properties of zinc oxide (ZnO) nanoparticles-coated cotton fabric have been investigated. The structures and morphologies of the ZnO nanoparticles were characterized and determined through x-ray diffraction (XRD) and transmission electron microscopy (TEM). ZnO nanoparticles show single phase material with common micro-rod shape particles with an average length and a diameter about 234 and 98 nm, respectively. ZnO nanoparticles diffuse into the fabric through spray coating method. Prior to the coating, surface preparation is the primary step toward treatment of the surface. The fabric surface pre-treatment consists of applying azelaic acid cured epoxy soybean oil as a crosslinking agent and dioctyl phthalate as the catalyst. This low-cost and eco-friendly combination of the cross-link and catalyst provides an interface adhesive bonding of ZnO nanoparticles layer and fabric surface. Then superhydrophobicity obtained by immersing the fabric into stearic acid. The superhydrophobic coating was confirmed by the water contact angle (WCA) measurement of 155°. The surface of ZnO nanoparticles-coated fabric was characterized by scanning electron microscopy (SEM). The antibacterial activity was examined against some common gram-positive, Bacillus subtilis, and gram-negative bacteria, Escherichia coli, by textile dilution method, using 200 µL of test microbe inoculum. The results show significant antibacterial activities of ZnO nanoparticles-coated fabrics against both bacteria.