Oliveira, N. T. C.
Nogueira, R. P.
Total Authors: 5
 UNED, Fac Ciencias, Dept Fis Matemat & Fluidos, Madrid 28040 - Spain
 Fed Univ Sao Carlos UFSCar, Dept Mat Engn DEMa, Sao Carlos, SP - Brazil
 Univ Grenoble Alpes, LEPMI, F-38000 Grenoble - France
 LEPMI, CNRS, F-38000 Grenoble - France
Total Affiliations: 4
Journal of Electroanalytical Chemistry;
JAN 15 2015.
Web of Science Citations:
A new direct approach for model identification is proposed. It allows a more accurate survey of the different relaxation processes yielding distinct time constants in electrochemical impedance spectroscopy. With the help of self-organized TiO2 nanotubes layers grown in pure Ti substrates, it is shown that the conventional impedance data representation methods are susceptible to miss some information that is made accessible by the frequency survey of alpha(eff), the effective CPE exponent parameter. In the specific case of the present work, the alternative representation proposed here shows that the electrochemical behavior of the TiO2 layers exposed to Ringer physiological solution is characterized by up to three time constants related to a simple double-layered structure composed by a dense barrier and the porous nanotubes one, instead of the ubiquitous two time constants mentioned in the literature for the same systems. (C) 2014 Elsevier B.V. All rights reserved. (AU)