Benzotriazole loaded CeO2 nano-containers towards superior anti-corrosive silane coating for protection of copper

In this work, we synthesized a superhydrophobic self-healing silane hybrid coating based on benzotriazole (BTA) loaded hollow CeO2 nano-capsules on copper substrate and evaluated the anti-corrosion and self-healing capability in 1 mol/L NaCl solution. The CeO2 nano-carriers possessed a high loading capacity of 24.7% for the BTA inhibitor. The constructed CeO2@BTA/silane composite shifted the corrosion potential of copper substrate to more inert value. Both the anodic and cathodic reaction rates during copper corrosion process were remarkably inhibited. The corrosion current density was over three orders of magnitude smaller than that of the neat silane coating. Electrochemical impedance spectroscopy revealed that the protection efficiency was 99.5% and the polarization resistance was reduced slightly after 15 days of corrosion for the prepared CeO2@BTA/silane hybrid coating. The prepared coating also exhibited an excellent self-healing ability to external damages by fast desorption of the BTA inhibitor.