Corrosion inhibition mechanism of copper by a novel benzotriazole-based multicomponent volatile corrosion inhibitors packaging film: Surface characterization and theoretical analysis

Abstract

Investigating the synergistic effects of multi-component complex formulation corrosion inhibitors is crucial for achieving optimal protection of metals against corrosion. The corrosion inhibition behaviors of benzotriazole(BTA) film and volatile corrosion inhibitors(VCIs) film on copper in a 3.5 wt% NaCl solution were systematically analyzed by weight loss tests, electrochemical analyses, FTIR, XRD, 3D electron microscopy, contact angle tests and SEM. Moreover, the synergistic effects between VCIs were illustrated molecularly by DFT and MD calculations. The findings revealed that the high corrosion inhibition efficiency was contingent upon the parallel adsorption orientations of VCIs, as well as the mixed physisorption and chemisorption mechanism. The corrosion inhibition effect of VCIs film on Cu was superior to that of BTA film, and the synergistic effect of the complex formulation VCIs was further confirmed by a higher adsorption energy and a denser parallel adsorption structure. VCIs demonstrated a favorable ability to form a protective film on the copper surface, with the efficacy increasing with the temperature of the inhibitor films formation treatment. The VCIs in the novel BTA multicomponent corrosion inhibitor packaging film functioned as mixed-type inhibitors, primarily inhibiting the cathodic reaction. This study holds significant importance in unraveling the mechanisms of the corrosion behavior regulated by VCIs.