Adsorption and corrosion inhibiting behavior of Lannea coromandelica leaf extract on mild steel corrosion

Lannea coromandelica leaf extract (LCLE) as a corrosion inhibitor in 1 M H2SO4 was investigated by weight loss and electrochemical techniques. Inhibition efficiency of LCLE was found to increase with increasing concentration but decreased with increasing temperature. Polarization measurements revealed that the LCLE acted as a mixed type inhibitor. Nyquist plots showed that on increasing the LCLE concentration, the charge transfer resistance increased and the double layer capacitance decreased. The adsorption of LCLE on mild steel obeyed the Lang-muir adsorption isotherm. FT-IR, XRD, SEM and AFM techniques confirmed the adsorption of LCLE on mild steel surface. (C) 2013 Production and hosting by Elsevier B.V. on behalf of King Saud University.