Benzotriazole as a volatile corrosion inhibitor during the early stage of copper corrosion under adsorbed thin electrolyte layers

[Display omitted] ► Inhibition effect under adsorbed thin electrolyte layer is investigated. ► Copper corrosion process is found under the control of CuCl2− mass-transport. ► An adsorption model of benzotriazole on copper surface is proposed. The inhibition effect of benzotriazole (BTAH) during the early stage of copper corrosion under adsorbed thin electrolyte layers (ATEL) was investigated. Electrochemical data show that BTAH suppressed the anodic corrosion reaction and inhibited copper corrosion under ATEL. The surface was examined by using a scanning electron microscopy, in situ atomic force microscopy, X-ray photoelectron spectroscopy, and attenuated total reflectance Fourier-transform infrared measurements. The inhibition of BTAH is attributed to its quick interaction with Cu(0) that formed a thin protective film in non-corroded areas and interaction with Cu(I) that formed a complex on Cu2O substrate in defect sites.