Influences of Electrolyte Characteristic on Morphology and Growth Mechanics of TiO2 Nanotube Arrays

The highly ordered TiO2 nanotube arrays were fabricated by anodic oxidation of titanium foil. The influences of electrolyte characteristic and concentration as well as anodization time on the morphology of TiO2 nanotube arrays were studied, and the growth mechanics were analyzed. Results show that regular ordered TiO2 nanotube arrays can be prepared in hydrofluoric acidic solution, the pipe diameters are uniform and the surfaces are smooth, but the lengthes are limlited in the range from 300nm to 350nm. TiO2 nanotube arrays and nanorod arrays can be obtained in high concentrate hydrofluoric acidic solution. TiO2 nanotube arrays with high slenderness ratios and rough surfaces are prepared in sodium fluoride and sodium sulfate electrolyte with lengths of 700nm which are longer than those prepared in hydrofluoric acidic electrolyte. TiO2 nanotube arrays with pipe diameters of about 150nm can also be prepared in glycol, ammonium fluoride and water ethyleneglycol electrolyte, the lengths of which can reach up to 6| .