Effect of Titanium Matrix Structure on Growth Morphology of Anodized TiO2 Nanotube Arrays for Applications in Photoelectrochemical Performances

Abstract

In the application of a solar cell and photocatalytic system, anodized titanium dioxide nanotube arrays (TNTs) have one-dimensional highly ordered nanotube structure, so they have attracted much attention. In order to form ordered TNTs, many factors, such as voltage, anodizing time, solvent type, and so on, need to be controlled. However, these factors have mainly focused on the effect of external conditions, while the effect of internal factors such as the crystal structure of the titanium substrate on the growth of nanotubes have been less investigated. In this paper, the titanium substrate tissue structure with a (002) preferred orientation was obtained by a rolling treatment. On this basis, TNTs with highly ordered structure were constructed, and the effect of the titanium substrate structure on the nanotube growth morphology was investigated. The changes in morphology were characterized by scanning electron microscopy, and the relationship between the changes in the crystal structure and morphology of TNTs was systematically analyzed by combining metallographic structure and X-ray diffraction data. The changes in the electrochemical behavior of the titanium substrates after rolling were examined through electrochemical methods. The above results show that there are a large number of dislocations and microscopic internal stresses in the grain structure of the titanium substrate after rolling, which leads to improvement of the corrosion resistance of the materials. The changes in the microstructure of these materials make the nanotube arrays have highly ordered structure and better photoelectrochemical properties, which provides an idea for improving their applications in photoelectrochemistry.