Long-Lasting Photocatalytic and Antimicrobial Activity of Cotton Towels Modified with TiO2 and ZnO Nanoparticles

Abstract

This study aimed to evaluate the durability of the photocatalytic and antimicrobial activities of ZnO and TiO2 nanoparticles (NPs)-modified 100% cotton terry textiles. SEM-EDX confirmed the long-lasting durability of the washing materials, and TGA analysis revealed that ZnO and TiO2 NPs can be found on the terry fabric surface; however, the amount of NPs decreased 10 times after 15 washes and 1.6 times after the subsequent 15 washes. The efficiency of self-cleaning properties and antimicrobial activity against five microorganisms (Staphylococcus aureus ATCC 6538, Escherichia coli ATCC 10536, Candida albicans ATCC 10231, Aspergillus niger ATCC 16404, and Bacillus subtilis NCAIM 01644) depended on UVA/B radiation intensity. The increase in UVA/B radiation intensity from 400 to 1400 µW/cm2 significantly increases the effectiveness of photocatalysis. Long-lasting self-cleaning properties characterised the tested fabric; however, stronger photocatalytic efficiency was observed in light with a greater intensity of UVA/B radiation. At the UVA/B radiation intensity of 1400 µW/cm2, a biocidal effect (R = 100%) against all tested microorganisms (E. coli, S. aureus. B. subtilis, C. albicans, and A. niger) was observed on the surface of materials. The lower UVA/B radiation intensity (400 µW/cm2) and 30 wash cycles reduce the antimicrobial activity of the material (R = 65.4–99.4%) for B. subtilis, C. albicans, and A. niger. The antimicrobial activity of washed materials modified with TiO2/ZnO nanoparticles can be increased by irradiation with a light bulb (1400 µW/cm2).