Electrochemical Approaches for Material Conservation: Experimental and Theoretical Insights Using a Biopolymer

Maltodextrin (MLD) is introduced as a novel, potent green inhibitor for the corrosion control of zinc in 0.1 sulfamic acid. The corrosion and inhibition studies were done by electrochemical techniques such as potentiodynamic polarisation measurements and electrochemical impedance spectroscopy technique. Conditions were optimised to get maximum inhibition efficiency by varying the concentration of the inhibitor in the temperature range of 303–323 K. Activation and thermodynamic parameters were evaluated and discussed in detail. Suitable mechanism was proposed for corrosion and inhibition process. Surface characterisation was done by SEM, EDX and AFM techniques before and after the addition of inhibitor. The density functional theory calculations were performed and compared with experimental observations. Results indicated that inhibition efficiency increased with the temperature and inhibitor concentration. Maximum inhibition efficiency was found to be 62.3% for the addition of 0.4 g L⁻¹ MLD. Theoretical calculations confirmed the experimental observations.