|M.Sc Student||Mahmud Auinat|
|Subject||Zinc Corrosion in Alkaline Solutions - Study of|
Inhibition Mechanism in the Presence of Organic
|Department||Department of Materials Science and Engineering||Supervisor||Full Professor Ein-Eli Yair|
The corrosion of the zinc electrode in alkaline cells and batteries is the main cause for self-discharge and relatively short shelf life. Zinc corrosion in alkaline media is controlled by the cathodic reaction of water reduction. One of the reduction products of this process is hydrogen gas and therefore, the ability to control the parasitic reaction of water reduction is a major a challenge. In order to minimize hydrogen release and to increase the corrosion resistance of the zinc metal in the alkaline media, organic inhibitors are widely employed in alkaline batteries. These inhibitors are environmentally benign and can serve as good alternative to mercury, which is considered to be highly efficient zinc corrosion inhibitor. In the present work we studied the effect of different polymeric organic inhibitors on the electrochemical behavior of zinc in strong alkaline electrolytes. The electrochemical studies included potentiodynamic and potentiostatic polarization along with linear polarization. The electrochemical measurements show that the studied inhibitors strongly decrease the rate of zinc cathodic reaction. Surface analysis obtained with the use of HRSEM and in situ AFM revealed different morphology characteristic developed at the zinc surface in the presence of the organic inhibitors. Detection of the adsorbed species on the zinc surface was performed with the use of FTIR spectroscopy.