On the estimation of standard adsorption free energy from corrosion inhibition efficiencies

The standard adsorption Gibbs energy ( ) is often estimated by assuming that the corrosion inhibition efficiency is equivalent to fractional surface coverage. However, Lindsay et al. [Corros. Sci. 155 (2019) 182–185] demonstrated that this assumption is not necessarily valid. Therefore, a model that maps inhibition efficiency to fractional surface coverage is developed herein to provide a more reliable estimation of . The model is validated with the experimental data of Lindsay et al.; the analysis confirms their conclusion that a significant error in estimation can be made by using inhibition efficiency as a proxy for surface coverage.