Cu/SiO₂ thin film on TiO₂ nanotubes on Ti15Mo alloy: surface and antibacterial evaluation Available to Purchase

In this study, the antibacterial efficacies of Cu and co-deposited Cu/SiO₂ thin films with 30% and 50% Cu concentrations, as deposited on TiO₂ nanotubes formed on a Ti15Mo alloy, were investigated against the Escherichia coli (E. coli) bacterium. Initially, bioactive TiO₂ nanotube arrays were fabricated on the Ti15Mo alloy via anodic oxidation at 35 V and room temperature. The anodically oxidised Ti15Mo surfaces were then annealed at 400°C under atmospheric conditions to obtain a crystalline structure without any morphological difference. Well-ordered nanotube arrays with an average diameter of 80 ± 0.7 nm were obtained. To enhance antibacterial activity, ≈10-nm-thick Cu, SiO₂, and Cu/SiO₂ thin films were deposited on the oxidised surfaces via magnetron sputtering using a co-deposition method. The thin film deposition did not affect the surface morphology of the TiO₂ nanotubes. The sputtered materials were homogeneously distributed across the entire surface and even within the nanotube interiors. All surfaces exhibited hydrophilic behaviour, with the Cu-coated surface showing the highest contact angle of 79.4°. Antibacterial testing against E. coli revealed that the Cu-coated surface exhibited a 57.9% improvement compared to bare Ti15Mo. The Cu:SiO₂ (50:50) thin film demonstrated the highest antibacterial efficacy, with an 80.7% improvement.