1. Introduction

Within the last decade, nanoscale and nanostructured metal oxide materials have strongly influenced numerous fields in science and technology. Among the various nanostructured oxide materials, TiO2 nanotube arrays (TNA) have received special attention due to its enhanced properties, cost-effective fabrication and higher surface-to-volume ratio [1]. TNA offers unique properties and a high functionality for various applications such as photocatalysis [2, 3], solar cell [4–6], biomedical [7, 8], and sensors [9, 10]. Their performance in various applications significantly determined by geometry, shape, and morphology of nanostructures [11]. In this concern, a

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and eproduction in any medium, provided the original work is properly cited. © 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

defined arrangement and a vertical and homogeneous alignment over the entire substrate surface, based on the self-organized anodic oxidation is pursued. Electrochemical anodization is widely used because of its controllable, reproducible results and simplicity of the process. The feasibility to tune the size and shape of nanotubular arrays to the desired dimensions and meeting the demands of specific applications by means of controlled anodic oxidation of the metal substrate have widen the application of TNA. Furthermore, it is a cost-effective method and the tubes prepared via this method have good adherent strength.
