Preparation and characterization of hollow ceria based smart anti-corrosive coatings on copper

Abstract

Hollow CeO2 nanoparticles were prepared and employed as nano-carriers to encapsule benzotriazole inhibitor. The benzotriazole loaded formulations were co-electrodeposited with silanol groups to fabricate a superhydrophobic self-healing silane nanocomposite on copper. The CeO2 nano-containers had a high loading amount of 21.7%. The release of BTA inhibitor in CeO2@BTA composite was pH responsive. Potentiodynamic polarization tests and electrochemical impedance spectroscopy were conducted to evaluate the corrosion protection and self-repairing ability of the deposited CeO2@BTA-silane nanocomposite in 1 M NaCl solution. Potentiodynamic polarization curves suggested that the CeO2@BTA-silane coated sample exhibited a noble corrosion potential and decreased corrosion current density in comparison with the uncoated specimen. The inhibition efficiency was found to be 99.7%. After 20 d immersion, the impedance modulus at 0.01 Hz decreased slightly to 557.2 kΩ.cm2 from 582.3 kΩ.cm2, revealing an outstanding chemical stability. Most of the artificial defects were sealed and repaired by the formed CeO2 passive coating and Cu-BTA complex. This paradigm offers an efficient strategy for constructing excellent anti-corrosion and self-healing coatings.