Synergistic effect of chloride assisted nanoporous anodic TiO₂ and silver nanoparticle modification on the corrosion behavior of additively manufactured Ti-6Al-4V implant alloy

Titanium alloys are widely used as implant materials; however, their long-term performance in physiological environments is often limited by corrosion and surface instability. In this study, nanoporous TiO2 layers were formed on additively manufactured Ti-6Al-4V by anodization in H2SO4 and H2SO4 + NaCl electrolytes and subsequently functionalized with silver nanoparticles (Ag NPs) by cyclic voltammetry. The structural, morphological, topographical, and electrochemical properties of the modified surfaces were systematically investigated using XRD, SEM/EDS, 3D profilometry, and electrochemical tests in simulated body fluid (SBF). Anodization significantly improved the corrosion resistance of Ti-6Al-4V, increasing the coating resistance into the 10(3)-10(4) M Omega & centerdot;cm & sup2; range and reducing the corrosion rate by up to similar to 84% compared with the untreated alloy. Samples anodized in H2SO4 + NaCl and further modified with Ag NPs exhibited the highest impedance values and the lowest corrosion current densities and retained high resistance after polarization, indicating superior electrochemical stability. Post-corrosion SEM/EDS analyses revealed reduced localized attack together with Ag- and Ca-P-containing surface layers on Ag NPs-modified samples. Overall, the results demonstrate that chloride-assisted anodization produces more compact and homogeneous nanoporous TiO2 layers, while Ag NPs modification enhances the stability of the oxide by sealing defects and promoting repassivation in SBF.

Journal

ELECTROCHIMICA ACTA

Year

2026

Volume

560

ISSN

0013-4686

eISSN

1873-3859

DOI

10.1016/j.electacta.2026.148671

WoS UID

WOS:001721190700001