Anodized multi – component titanium alloys carrying antibacterial features

• Published in: Applied surface science 2023-03, Vol.613, p.156009, Article 156009
• Main Authors: Kozak, Magda, Mazierski, Paweł, Baluk, Mateusz, Żebrowska, Joanna, Lisowski, Wojciech, Trykowski, Grzegorz, Skowron, Piotr, Zaleska-Medynska, Adriana
• Format: Article
• Language: English
• Subjects: Anodization; Heterogeneous photocatalysis; Nanotubes; Physicochemical properties of NTs; Removal of microbiological pollutants; Ternary alloys
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2022.156009

[Display omitted] •Ternary alloys Ti89Ag10Pt1, Ti90Ag5Cu5 andTi94Ag5Au1 allowed formation of nanotubular layers.•TiO2/Ag2O/Cu2O, TiO2/Ag2O/PtOX and TiO2/Ag2O/Au0 were obtained within nanotube layers.•Alloy nanoparticles of Ag2O/Cu2O, Ag2O/PtOX and Ag2O/Au0 were distributed along the nanotubes.•Enhanced inactivation of E.coli, S. aureus and Clostridium sp. under visible light was observed.•TiO2/Ag2O/Au0 nanotube layers were characterized by the highest inactivation of bacteria.•Efficiency of 99.9, 90 and 92.8% in terms of S.Aureus, E.Coli and Clostridium sp were reached, respectively. TiO2 nanotubes (NTs) obtained from multicomponent alloys by electrochemical anodization are prospective nanomaterials in photocatalytic reactions as well as in disinfection processes. New nanotubular structures were obtained in the anodization process from three – component alloys consisting of metals characterized by antibacterial properties and improved charge transfer. TiO2/Ag2O/Cu2O, TiO2/Ag2O/PtOX and TiO2/Ag2O/Au0 heterojunctions were obtained for the first time. The physicochemical properties of NTs layers were characterized by XRD, DRS, UV–vis, SEM, TEM, XPS and EDX. Antimicrobial properties were investigated in three model reactions – under visible irradiation (λ > 420 nm), in the dark and without photocatalysts in the presence of E.coli, S.aureus, Pseudomonas aeruginosa, K.oxytoca and Clostridium sp. Enhanced activity under visible irradiation was observed. The most efficient process of bacteria inactivation was obtained by TiO2/Ag2O/Au0 NTs. TEM images of bacteria after the process were prepared. The Mechanism of bacteria inactivation was studied. It is assumed that during the process the transfer of photoexcited electron from Ag2O to TiO2 emerged. Photogenerated electrons and holes get across with other substances to create reactive oxygen species including ̇O2, which led to damage of the bacteria cells.