Silver film on nanocrystalline TiO₂ support: Photocatalytic and antimicrobial ability

Highlights: • Simple photocatalytic rout for deposition of Ag on nanocrystalline TiO₂ films. • High antibactericidal efficiency of deposited Ag on TiO₂ support. • Improved photocatalytic performance of TiO₂ films in the presence of deposited Ag. - Abstract: Nanocrystalline TiO₂ films were prepared on glass slides by the dip coating technique using colloidal solutions consisting of 4.5 nm particles as a precursor. Photoirradiation of nanocrystalline TiO₂ film modified with alanine that covalently binds to the surface of TiO₂ and at the same time chelate silver ions induced formation of metallic silver film. Optical and morphological properties of thin silver films on nanocrystalline TiO₂ support were studied by absorption spectroscopy and atomic force microscopy. Improvement of photocatalytic performance of nanocrystalline TiO₂ films after deposition of silver was observed in degradation reaction of crystal violet. Antimicrobial ability of deposited silver films on nanocrystalline TiO₂ support was tested in dark as a function of time against Escherichia coli, Staphylococcus aureus, and Candida albicans. The silver films ensured maximum cells reduction of both bacteria, while the fungi reduction reached satisfactory 98.45% after 24 h of contact