title: Formation process of TiO2 nanotube arrays prepared by anodic oxidation method.
abstract: TiO2 nanotube array thin films have great potential in many fields, such as solar cell, photo catalyst, photo-induced cathodic protection for metals and bioactivity. In order to investigate the formation process of the TiO2 nanotube array thin films, the EIS spectrum and current density were measured during the anodic oxidation. The results showed that the formation process could be divided into four stages. The current density decreased sharply at the first stage, and then increased at the second stage, followed by declining and finally remained constant value. In addition, the current density increased with the anodic voltage. The EIS spectrum varied in different stage. The simulated circuit was composed three sections, the first sections indicated the resistance of the electrolyte, the second one gave the double layer structure between the electrolyte and titanium electrode, the third one was a inductive loop, which represented the anions absorbed on the surface of the TiO2 nanotube's wall. The more cations were absorbed, the higher value of the inductive loop would be. The EIS results showed that the value increased with the outer voltage, which means that more cations were absorbed under the higher anodic voltage.
authors.affiliation: Key Laboratory of Advanced Functional Materials, School of Materials and Engineering, Beijing University of Technology, Beijing 100124, China.
authors.forename: Hongyi
authors.initials: H
authors.lastname: Li
authors.forename: Man
authors.initials: M
authors.lastname: Liu
authors.forename: Hong
authors.initials: H
authors.lastname: Wang
authors.forename: Junshu
authors.initials: J
authors.lastname: Wu
authors.forename: Penglei
authors.initials: P
authors.lastname: Su
authors.forename: Dasheng
authors.initials: D
authors.lastname: Li
authors.forename: Jinshu
authors.initials: J
authors.lastname: Wang