Biomedical implants and devices that penetrate soft tissue are highly susceptible to infection, but also accessible for UV induced decontamination through photocatalysis if coated with suitable surfaces. As an on-demand antibacterial strategy, photocatalytic surfaces should be able to maintain their antibacterial properties over repeated activation. This study evaluates the surface properties and photocatalytic performance of titania films obtained by H 2 O 2 -oxidation and heat treatment of Ti and Ti-6Al-4V substrates, as well as the prospect of assisting photocatalytic reactions with H 2 O 2 for improved efficiency. H 2 O 2 -oxidation generated a nanoporous coating, and subsequent heat treatment above 500°C resulted in anatase formation. Tests using photo-assisted degradation of rhodamine B showed that prior to heat treatment, an initially high photocatalytic activity (PCA) of H 2 O 2 -oxidized substrates decayed significantly with repeated testing. Heat treating the samples at 600°C resulted in stable yet lower PCA. Addition of 3% H 2 O 2 during the photo-assisted reaction led to a substantial increase in PCA due to synergetic effects at the surface and H 2 O 2 photolysis, the effect being most notable for non-heat treated samples. Both heat treated and non-heat treated samples showed stable PCA through repeated tests with H 2 O 2 -assisted photocatalysis, indicating that the combination of H 2 O 2 -oxidized titania films, UV light and added H 2 O 2 can improve efficiency of these photocatalytic surfaces.
Highlightsï·ï Ti and Ti64 substrates were surface modified by H 2 O 2 -oxidation and heat treatments.ï·ï TiO 2 /UV/H 2 O 2 synergy effects significantly boosted rhodamine B degradation.ï·ï 3% H 2 O 2 addition increased stability over repeated use.