Electrochemical response of TiO2 anodic layers fabricated on Ti6Al4V alloy with nanoporous, dual and nanotubular morphology

Abstract

Nanoporous, dual and nanotubular anodic layers were grown on Ti6Al4V. Impedance spectra for nanoporous and dual revealed a response controlled by the barrier layer. Conversely, the response of the nanotubular layers depends on size of the intertubular space and immersion time. At immersion times ≥24 h, the spectra of the nanotubular layers with intertubular spaces ≤20 nm show the response of the barrier layer and the oxide covering the substrate. While for the nanotubular with intertubular spaces of ∼30 nm, the spectra show only the contribution of the substrate at the bottom of the intertubular spaces.