TiO2 nanotube arrays grown in ethylene glycol-based media containing fluoride: Understanding the effect of early anodization stages on the morphology

BROENS, MARTÍN I.; CERVANTES, WILKENDRY RAMOS; COLLAO, ANDRÉS M. ASENJO; IGLESIAS, RODRIGO A.; TEIJELO, MANUEL LÓPEZ; LINAREZ PÉREZ, OMAR E.

JOURNAL OF ELECTROANALYTICAL CHEMISTRY - (Print)

ELSEVIER SCIENCE SA

Año: 2023

1572-6657

n this work, we develop a phenomenological model describing the growth ofTiO2 nanotube arrays (NTA-TiO2) by titanium anodization in ethylene glycol-basedelectrolytes containing fluoride. NTA-TiO2 formation is described in terms of the well-known High-Field mechanism (HFM) considering film thinning by dissolution, and theelectronic current contribution according to the Oxygen Bubble Mold (OBM) model, asit has been previously reported. For the first time, the inclusion of the nucleation ofoxygen bubbles as the rate determining step at early anodization times is considered. Bysimultaneous fitting of the potentiostatic profiles and the time evolution of𝑗/𝑡morphological features such as pore radius, layer thickness and density of pores, thebehavior observed for several experimental conditions is accurately described, in contrastto previously reported Field Assisted Dissolution (FAD) and OBM models. Proposedmodel allows obtaining physical and phenomenological information con