Corrosion inhibition effect on copper by 1-hydroxybenzotriazole and sodium molybdate

The corrosion inhibition effect of 1-hydroxybenzotriazole and sodium molybdate for copper in ASTM D 1384 simulation atmosphere corrosive liquid was investigated by using electrochemical impedance spectroscopy, scanning Kelvin probe (SKP) and quartz crystal microbalance (QCM). The results revealed that BTAOH and Na₂MoO₄ compounding in 2 to 1 could fast form adsorption film and oxidation film on copper surface, prevent the adsorption of corrosive ions on the surface of copper, and improve the charge transfer resistance. In corrosion inhibitor containing media, the copper surface was smooth and dense, while corrosion products of copper in simulation atmosphere corrosive liquid piled up on the surface in rendering granular. The scan Kelvin probe was used to obtain corrosion potential maps on copper surface under different hours. We can see that after 96 hours, the change of Kelvin potential on copper surface was very small, only slight corrosion occurred.