Fluoride-free porous TiO2 fabricated by polymer resin assisted-anodization

초록

Titanium (Ti) is currently under investigation to fabricate the oxide films with unique nanostructures through anodization. Its robust corrosion resistance, semiconductor properties, and lightweight nature make it a preferred choice in various sectors such as medicine, photocatalysis, and aviation. Traditionally, anodization is performed in an electrolyte containing fluoride ions. However, this method results in weak adhesion between the oxide film and Ti substrate due to the fluoride-rich layers. Recently, additional treatment after anodization was researched to enhance the adhesion properties. However, there is a fundamental limitation on anodization using electrolytes with fluorine ions. In this study, we successfully fabricated an oxide film with excellent adhesive strength using a polymer resin-assisted anodization that does not induce a fluoride-rich layer. By adjusting the reaction voltage, we could control the thickness and pore size of the oxide film. We compared the surface roughness and hardness of the oxide films with and without fluoride-rich layers. Additionally, we investigated the morphology and crystallinity using scanning electron microscopy (SEM) and X-ray diffraction (XRD). By introducing a novel anodization mechanism, we have broadened the application scope of anodized titanium oxide, which was previously limited due to the fluoride-rich layer.