In this study, a combination of scanning tunneling microscopy (STM), scanning tunneling spectroscopy (STS), atomic force microscopy (AFM), scanning Kelvin probe force microscopy (SKPFM), and density functional theory is applied to investigate the evolution of Volta potential and electronic properties of TiO2/Cu2O coupled oxides in presence of chloride-containing corrosive solution. Volta potential and the band gap of Cu2O are increased in presence of chloride ion due to paratacamite (Cu-2(OH)(3)Cl) formation whereas the opposite is seen for TiO2 due to the formation of H4TiO4. The results shows a good correlation between the measured Volta potential difference and the observed corrosion behavior. (C) 2018 Elsevier B.V. All rights reserved.