Inhibitive Action of Sulfide Ions on Corrosion and Enhancing Charge-Discharge Efficiency of Zinc and Zinc-Indium Alloy as Anode for Alkaline Batteries

The obtained data reveal that the coverage of surface (theta) and protection efficiency (eta%) for the studied electrodes increases gradually as the inhibitor concentration increases. Tafel plot is carried out at variant temperatures in the investigated basic electrolyte containing 1x10-1 M of S ions. This study reveals that the activation energy barrier of the studied alloy is higher than that of pristine zinc anode at a fixed inhibitor concentration. It is observed that Goads. and eta% values rise with rising solution temperature, indicating that S ions adsorption on the studied electrode surfaces occurs by a chemisorption mechanism. Other calculations are made for the additional thermodynamic parameters such as Hoadsand Soads. The zinc anodes get more efficient when S ions are added to the solution, considerably decreasing electrochemical polarization. In addition, the presence of indium sulfide improves the exposed surface area of the alloy, supplying additional improvement in charge-discharge efficiency. Density functional theory (DFT) is utilized to extract the quantum data to acquire a deeper understanding of the chemical processes between sulfide ions at the interface. The study analyses the inhibition effect of sulfur ions on the corrosion of zinc and zinc-indium alloy in alkaline media. Adding sulfur ions is found to improve surface coverage, decrease corrosion current density, increase inhibition efficiency, and enhance the charge-discharge characteristics. DFT calculations and surface analyses provid insights into the chemical interactions between the sulfur inhibitor species and alloy surfaces. image