Improving pitting corrosion resistance of the commercial titanium through graphene oxide-titanium oxide composite

Talal A Aljohani; Muntathir I Albeladi; Basheer A Alshammari

doi:10.1016/j.heliyon.2021.e07289

Improving pitting corrosion resistance of the commercial titanium through graphene oxide-titanium oxide composite

Heliyon. 2021 Jun 12;7(6):e07289. doi: 10.1016/j.heliyon.2021.e07289. eCollection 2021 Jun.

Authors

Talal A Aljohani¹, Muntathir I Albeladi¹, Basheer A Alshammari²

Affiliations

¹ National Centre for Chemical Technologies, King Abdulaziz City for Science and Technology (KACST), Riyadh, Saudi Arabia.
² Materials Science Research Institute, King Abdulaziz City for Science and Technology (KACST), Riyadh, Saudi Arabia.

Abstract

Titanium oxide has been commonly used for wide range of applications due to excellent corrosion resistance. This study presents the impact of graphene oxide (GO) addition to titanium oxide as coating materials during titanium anodization process on the corrosion behaviour. The GO was prepared by electrochemical exfoliation using low voltage mode in a sodium sulphate electrolyte, which is easier and more environmentally friendly compared to the chemical approach. Raman and scanning electron microscope were used to examine the success of the exfoliation process. The surface morphologies and potentiodynamic polarization results indicate that the addition of GO significantly inhibit the pitting corrosion and stabilize passivation current densities over wide ranges of anodic potentials. The untreated titanium, however, noticeably displayed fluctuation of anodic current densities, confirming the presence of pitting corrosion. The results obtained by electrochemical impedance spectroscopy (EIS) also confirm that the addition of GO enhanced corrosion protection even at higher frequency ranges. The cyclic polarization scan results show a positive shift in the re-passivation potential E_rep after the addition of GO. This work emphasizes that the addition of GO during anodization of titanium not only protect its surface from pitting corrosion but also provide a strong passive layer.

Keywords: Electrochemical graphene oxide exfoliation; Electrochemical impedance spectroscopy (EIS); Electrochemical oxidation; Nanoparticles; Polarization resistance.