Electrochemical and surface analysis studies on corrosion inhibition of Q235 steel by imidazoline derivative against CO2 corrosion

The inhibition performance of a newly synthesized thioureido imidazoline inhibitor (TAI) in CO2 corrosion was studied by using electrochemical impedance spectroscopy (EIS) atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) Results show that the values of inhibition efficiency show peak-value-phenomenon at concentration of 0 15 mmol dm(-3) owing to the change of adsorption mode The adsorption of protonated TAI molecules on the negatively charged steel surface makes the potential of zero charge (PZC) shift to positive direction and the long-range electrostatic exclusive forces between AFM tip and sample surface are reduced by screening effect of surface charges (C) 2010 Elsevier Ltd All rights reserved