Abstract:The corrosion inhibition property of PEG600 and In(OH)₃ as composite corrosion inhibitors for secondary alkaline zinc electrodes was studied, and the inhibition efficiency was determined as 81.9%. The research focused on the mechanism by the methods of electrochemical impedance spectroscopy, polarization curves and IR spectroscopy. The results indicate that the corrosion inhibition effectiveness is attributed to the joint inhibition of anodic zinc dissolution and cathodic hydrogen evolution. And the anodic process is depressed to a greater extent than the cathodic process. The synergistic mechanism of the composite inhinbitors proves to be the enhancement of adsorption of PEG600 by In(OH)₃. Potentiostatic experiment results and SEM images verify the inhibition of dendritic growth by the composite inhibitors.

Key words: secondary alkaline zinc anode; composite corrosion inhibitors; corrosion inhibition; synergistic effect; dendritic growth