Characterization and photocatalytic activity of TiO 2 nanoparticles on cotton fabrics, for antibacterial masks.

The in-situ impregnation of two commercial cotton fabrics (lab coat and Indiolino) with TiO 2 nanoparticles (TiO 2 -NPs) was carried out. For this, two commercial cotton fabrics were dipped in titanium isopropoxide, titanium butoxide and titanium tetrachloride solutions to the TiO 2 -NPs formation and in-situ TiO 2 -NPs impregnation on the cotton fabric surface by the sonochemical, hydrothermal and solvothermal methods, respectively. The impregnated fabrics were characterized by ATR-FTIR, SEM-EDS, Raman, UV-Vis, DRS and tension tests. The results showed the successful formation and impregnation of TiO 2 -NPs on both cotton fabrics. The leaching of TiO 2 -NPs from cotton fabrics was negligible after several washing cycles. The self-cleaning properties and antibacterial activity of TiO 2 -NPs functionalized cotton fabrics were assessed by photocatalytic and antibacterial tests. The photocatalytic activity was determined by the degradation of methylene blue dye under UV and solar irradiation. The materials showed good photoactivity, since MB was degraded up to 99% under solar and UV irradiations in 60 min. The bactericidal capacity of the TiO 2 -NPs on fabrics, evaluated in-situ by SEM, showed that Indiolino presented the best antibacterial properties against Escherichia coli and Bacillus pumilus.