Empirical kinetics for the growth of titania nanotube arrays by potentiostatic anodization in ethylene glycol

摘要

The goal of this research was to describe the effects of the main anodization variables on themorphology of the resulting titania nanotube arrays. Four variables were considered in this study:applied voltage, fluoride and water concentrations, and time. The first three variables were studiedsimultaneously in a central composite design of experiments using SEM measurements of tubelength as the response variable. The effect of time was modeled using transferred charge as theresponse variable. A field assisted oxidation-dissolution growth model was validated over a broadrange of experimental conditions under which tube growth can be accurately predicted directlyfrom the current transients using Faraday’s laws. The effects of anodization variables weredescribed based on this model and a simple, empirical kinetic expression was obtained andsuccessfully tested against data from other authors with fairly small errors over a broad range ofconditions.