Synergistic Inhibitory Effect of Potassium Sodium Tartrate Tetrahydrate and Sodium Stannate Trihydrate on Self‐Corrosion of Aluminum in Alkaline Aluminum‐Air Batteries

Abstract To promote the efficiency of aluminum‐air batteries, the present paper proposes using inhibitor for decreasing anodic corrosion; therefor, the self‐corrosion of pure aluminum sheet (PAS) in KOH (1 M) solution at different concentrations of two inhibitors; potassium sodium tartrate tetrahydrate (STT) and sodium stannate trihydrate (SST) has been investigated both individually and collectively. The characteristics of PAS were studied through electrochemical methods including Tafel polarization curves, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), and energy‐dispersive X‐ray spectroscopy (EDS). The results indicate that inhibition efficiencies for both inhibitors (STT and SST) increased with a rise in concentration of the inhibitors reaching a maximum in one certain concentration called optimum concentration. The constant current discharge plots for the assembled prototype aluminum‐air battery were also obtained, further confirming the aforementioned results. Finally, the calculated anode efficiency results indicate that the addition of mix inhibitor into electrolyte demonstrates the highest impact compared with the others, which should be attributed to the significantly reduced self‐corrosion reaction.