Adsorption and corrosion inhibition of phytic acid calcium on the copper surface in 3 wt% NaCl solution

The adsorption and corrosion protection effect of phytic acid calcium (PAC) film on the copper surface in 3 wt% NaCl solution was investigated using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and Raman spectroscopy. Polarization curves indicate that PAC is a mixed inhibitor, affecting both cathodic and anodic corrosion currents. The inhibition efficiency of PAC film reached 92.53% at an optimized condition. Adsorption of PAC molecules on the surface followed Langmuir adsorption isotherm and the standard Gibbs energy of -37.32 kJ mol(-1) indicated a chemisorptive way. Raman studies suggested that PAC molecule chemically anchored at the surface via P-O groups. (c) 2014 Elsevier Ltd. All rights reserved.