Synthesis of TiO2 nanotubes via electrochemical anodization with different water content

Effect of the electrolyte chemical nature on the formation and characteristics of TiO2 nanotubes synthesized by anodic oxidation using a Ti cathode

“…This figure shows the formation of a compact array of TNT-I, adjacent and parallel to each other, with a structural regularity that contrasts with their base, which indicates that there was uniformity in the length of the TNT-I. In addition, a conical shape is shown with an apparently rough outer wall that presents undulations, attributed to the high water content of the electrolyte as has been reported earlier by [9,12]. In this figure, severe fractures along the TNT-I, seen as ruptures and tilt of the nanotubes wall are visible.…”

“…TiO 2 is a relatively abundant semiconductor material. Due to its excellent properties such as low toxicity, excellent stability to corrosion, and good chemical and biological stability, TiO 2 is used in the fabrication of solar and fuel cells, paints, cosmetics, inks printing, ceramics, textiles, pavements coverings, energy storage devices, hydrogen production, biomedical applications, and as a photocatalyst for water and air purification, metal oxidation, and inactivation of viruses and pathogenic microorganisms [1][2][3][4][5][6][7][8][9]. Nanostructured TiO 2 can be prepared in the form of a powder or thin films, produced using a variety of techniques such as thermal oxidation, spraying, chemical or physical deposition in the vapor phase, sol-gel, solvo-thermal processes, inverse micellar, and hydrothermal [7,[10][11][12][13][14].…”

“…However, other anodization parameters such as the geometry, size, material, and cleaning of the electrodes; distance between the electrodes; type and speed of stirring; the pH, water content, temperature, and chemical nature of the electrolyte have been less studied, while regarding the reuse of electrolytes no report was found. Other characteristics such as a change in the volume of the electrolyte or the potential sweep speed do not affect the physical characteristics of the nanostructures [9,12,[26][27][28][29][30].…”

“…Alternatively, the TiO 2 nanostructures that present characteristics such as biocompatibility, photocatalytic activity and superhydrophilicity have been found to offer great potential in biomedical applications, and photoelectrochemical and photocatalytic processes [8,9,21,24,29,[33][34][35][36][37][38]. In this regard, the advantage of TNT over other nanostructures such as nanoparticles, nanowires, nanobars, and nanofibers is the area provided by their internal and external surfaces.…”

“…A thermal treatment of the anodized substrates at 300-350 °C generally allows the amorphous structure of the anodic oxide to transform into photoactive crystalline phases [4,12,19,21,24,[42][43][44]. Thus, using anodic oxidation, the pores of the TNT grow directly from the Ti substrate (TNT/Ti) generating good size, uniformity, order, electrical conductivity, and strong mechanical adhesion [9,19,44].…”