Evaluation of TiO 2 and ZnO atomic layer deposition coated polyamide 66 fabrics for photocatalytic activity and antibacterial applications

Abstract

Atomic layer deposition (ALD) is a versatile technique to functionalize textile substrates due to its ability to create conformal films on the fibers' surface. Photocatalytic activity and antibacterial activity of TiO2 and ZnO films deposited onto polyamide 66 fabrics were investigated. ALD coated fabrics were examined to eliminate Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria with ISO 20645 and AATCC 100 standard methods. Both materials were only slightly successful for the elimination of E. coli. However, ZnO films were more effective in killing S. aureus bacteria than TiO2 films independent of incubation conditions (i.e., under dark or ambient light). Deposited films were characterized using SEM, FTIR, UV-Vis, and XPS spectroscopy techniques. Furthermore, the samples' photocatalytic activity was determined by measuring methylene blue degradation as a model organic molecule showing that ZnO films were better photocatalysts as deposited. The films' antibacterial mechanism is mainly due to ions dissolving from the films into the bacterial solutions.