Atomic layer deposition of TiO2 and Al2O3 thin films for the electrochemical study of corrosion protection in aluminum alloy cans used in beverage

• Published in: Materials research express Vol. 7; no. 7; pp. 076408 - 76420
• Main Authors: Dias, V M, Chiappim, W, Fraga, M A, Maciel, H S, Marciano, F R, Pessoa, R S
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.07.2020
• Subjects: Aluminum base alloys; Aluminum oxide; atomic layer deposition; Atomic layer epitaxy; Circuits; Comparative studies; Corrosion; Corrosion prevention; Corrosion tests; Electrochemical impedance spectroscopy; Resins; Substrates; Thickness; Thin films; Titanium; Titanium dioxide
• ISSN: 2053-1591
• DOI: 10.1088/2053-1591/aba557

Titanium dioxide (TiO2) and aluminum oxide (Al2O3) thin films, with thicknesses around 100 nm, were grown on commercial pure- and resin-coated Al substrates using the atomic layer deposition (ALD). A comprehensive and comparative study of corrosion protection was carried out by linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) measurements for a set of six samples: two reference samples (Al-bare and Al-resin), and four ALD coated samples ( Al-TiO2, Al-Al2O3, Al-resin-TiO2, and Al-resin-Al2O3). The LSV and EIS results display good mutual agreement, indicating a higher protection efficiency of all ALD-coated samples after immersion in NaCl. When compared to Al-bare, all ALD coated samples (TiO2 or Al2O3) showed a corrosion inhibition enhancement factor of 99%. Besides, our results demonstrated that Al-resin+Al2O3 has 24.95% and 33.40% more corrosion inhibition than Al-Al2O3 and Al-resin, respectively. EIS data were fitted by an equivalent electric circuit (EEC). The Nyquist and Bode plots from the experiments showed that ALD films are a potential candidate for altering/improving commercial resin-coated Al cans.