Copper Corrosion inhibition by a Quaternary Ammonium Salt-assisted Benzotriazole

Abstract

Quaternary ammonium salt (QAS) Hyamine 1622 and benzotriazole (BTAH) were used to form a protective layer on copper surface to resist the corrosion by immersing the copper into the inhibitors-containing solutions. The inhibitor’s anticorrosion properties are studied in neutral 3.5 wt.% NaCl medium by anodic polarization, Tafel polarization, electrochemical impedance spectroscopy (EIS) and OCP exposure. The surface characterization is analyzed by Contact angle(CA) measurement, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy(SEM). The electrochemical tests show that they can act as single inhibitor to form a passive layer to resist Cu corrosion, and the anticorrosion properties of Cu can be improved by using binary Hyamine 1622/BTAH inhibitors. XPS results indicate that both BATH and Hyamine 1622 molecule can be chemisorbed onto the copper surface and make complex films with Cu species. CA measurement revealed the enhancement of hydrophobicity by combining QSA with BTAH. OCP exposure in neutral medium for 72 h evidently reveals that the passive layer formed by binary inhibitors decreases the pit corrosion. Better hydrophobic nature and more compact passive layer give rise to excellent inhibition properties of binary inhibitors.

Keywords

• copper anticorrosion
• quaternary ammonium salt
• benzotriazole