Influence of water content on controlling parameters of morphology of TiO₂ nanotube

TiO2 nanotube arrays were fabricated by anodic oxidation of titanium foil in ethylene glycol electrolytes with different amount of water. The influences of water content on the conductivity, viscosity and current were studied by the curve of conductivity, viscosity and the loop current recorded online in the reaction process changing with time. The relationship between the dimension and the quantity of electric charge consumption of chemical dissolution of TiO2 oxide films was analyzed. The results show that cubics function relationship existed between viscosity and water content and between conductivity and water content. The correlation coefficients were 0.992 5 and 0.977 8, respectively. Viscosity of electrolyte increased slowly in the reaction process. Viscosity of electrolyte with different water content was not similar. Diversities in the number of H+ and OH- of electrolyte, as well as different transfer rate of F- resulted in the variation trends of current-time curve and conductivity-time curve. When the water content was 4%, 5%, 6% and 10%, the nanotubes morphology was highly in order and there was little debris on the surface of the TiO2 nanotube arrays. The nanotubes diameter was between 50 nm and 72 nm, and the length ranged from 850 nm to 1.90 m. The quantity of electric charge consumption of chemical dissolution of TiO2 oxide films in line with volume of TiO2 films dissolved in the electrolyte, the volume of TiO2 films dissolved increased with the increasing of the quantity of electric charge consumption of chemical dissolution of TiO2 oxide films, which provided a theoretical basis for the preparation of morphology and dimension controllable nanotube arrays.