The effect of 2-Pyridinecarbonitrile (2-PCN) was studied on mild steel (MS) corrosion in 0.1 mol L-1 HCl by electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR) and potentiodynamic polarization measurements. The surface morphologies of the MS were investigated in the inhibitor-free and in the presence of 10 mmol L-1 2-PCN containing corrosive media, at 120 h exposure period by scanning electron microscopy (SEM). The mechanism of adsorption was determined from the potential of zero charge (E-pzc). 2-PCN adsorption on the MS surface obeyed the isotherm of Langmuir and the thermodynamic parameters K-ads; Delta G(ads)degrees were also calculated and discussed. (C) 2014 Elsevier Ltd. All rights reserved.