Biferrocenyl Schiff bases as efficient corrosion inhibitors for an aluminium alloy in HCl solution: a combined experimental and theoretical study

• Published in: RSC advances Vol. 1; no. 13; pp. 7585 - 7599
• Main Authors: Nazir, Uzma, Akhter, Zareen, Janjua, Naveed Kausar, Adeel Asghar, Muhammad, Kanwal, Sehrish, Butt, Tehmeena Maryum, Sani, Asma, Liaqat, Faroha, Hussain, Rizwan, Shah, Faiz Ullah
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 20.02.2020; The Royal Society of Chemistry
• Subjects: Aluminum base alloys; Chemistry; Chemistry of Interfaces; Correlation analysis; Corrosion; Corrosion inhibitors; Corrosion prevention; Electrochemical impedance spectroscopy; Ethane; Fourier transforms; Gränsytors kemi; Imines; Infrared spectroscopy; NMR; Nuclear magnetic resonance; Organic chemistry; Polarization; Quantum chemistry; Quantum mechanics; Scanning electron microscopy; Spectrum analysis; Weight loss measurement
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/c9ra10692h

The corrosion inhibitive capabilities of some ferrocene-based Schiff bases on aluminium alloy AA2219-T6 in acidic medium were investigated using Tafel polarization, electrochemical impedance spectroscopy (EIS), weight loss measurement, FT-IR spectroscopy and scanning electron microscopic (SEM) techniques. The influence of molecular configuration on the corrosion inhibition behavior has been explored by quantum chemical calculation. Ferrocenyl Schiff bases 4,4′-(((ethane-1,2-diylbis(oxy))bis(4,1-phenylene))bis(methaneylylidene))bis(azaneylylidene))bisferrocene ( Fcua ), 4,4′-(((ethane-1,2-diylbis(oxy))bis(2-methoxy-1,4-phenylene))bis(methaneylylidene))bis(azaneylylidene))bisferrocene ( Fcub ) and 4,4′-(((ethane-1,2-diylbis(oxy))bis(2-ethoxy-1,4-phenylene))bis(methaneylylidene))bis(azaneylylidene))bisferrocene ( Fcuc ) have been synthesized and characterized by FT-IR, 1 H and 13 C NMR spectroscopic studies. These compounds showed a substantial corrosion inhibition against aluminium alloy in 0.1 M of HCl at 298 K. Fcub and Fcuc showed better anticorrosion efficiency as compared with Fcua due to the electron donating methoxy and ethoxy group substitutions, respectively. Polarization curves also indicated that the studied biferrocenyl Schiff bases were mixed type anticorrosive materials. The inhibition of the aluminium alloy surface by biferrocenyl Schiff bases was evidenced through scanning electron microscopy (SEM) studies. Semi-empirical quantum mechanical studies revealed a correlation between corrosion inhibition efficiency and structural functionalities. The anticorrosion activity of biferrocenyl Schiff bases on AA2219-T6 in acidic medium were studied using Tafel polarization, electrochemical impedance spectroscopy, weight loss analysis, FT-IR spectroscopy and scanning electron microscopic technique.