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

LINAREZ PÉREZ, OMAR E.

JOURNAL OF ELECTROANALYTICAL CHEMISTRY - (Print)

ELSEVIER SCIENCE SA

Año: 2023 vol. 935 p. 117314 - 117314

1572-6657

n this work, we develop a phenomenological model describing the growth of TiO2 nanotube arrays (NTA-TiO2)by titanium anodization in ethylene glycol-based electrolytes containing fluoride. NTA-TiO2 formation is describedin terms of the well-known High-Field mechanism (HFM) considering film thinning by dissolution, andthe electronic current contribution according to the Oxygen Bubble Mold (OBM) model, as it has been previouslyreported. For the first time, the inclusion of the nucleation of oxygen bubbles as the rate determining step at earlyanodization times is considered. By simultaneous fitting of the potentiostatic profiles and the time evolutionof morphological features such as pore radius, layer thickness and density of pores, the behavior observed forseveral experimental conditions is accurately described, in contrast to previously reported Field Assisted Dissolution(FAD) and OBM models. Proposed model allows obtaining physical and phenomenological information concerningthe format