TiO 2 nanotubes produced on thin titanium wires using aqueous electrolytes

In this experimental work, homogeneous nanotube layers were successfully formed by anodization on titanium wires with diameters lower than 200 µm employing an aqueous anodizing solution composed of carboxymethylcellulose and sodium fluoride. Homogeneous nanotube layers were formed only when the titanium wires were electropolished. After heat treatment at 350 and 600°C, the nanotubes were transformed from amorphous phase into anatase phase or a mix between anatase and rutile phases. After both heat treatments, the nanotube coatings remained uniform; namely, no apparent cracks, critical defects, or coating delamination were seen. To the best of our knowledge, a homogeneous nanotube coating composed of anatase or a mix between anatase and rutile phases on titanium wires with diameters lower than 200 µm has not been reported. These coatings may be potentially useful in a variety of fields, including biomedicine, sensing, and catalysis.