Synergistic Effect of Vanadate and Nanoclay Hybrid Inhibitor on the Self-Corrosion and Discharge Activity of Al Anode in Alkaline Aluminum-Air Batteries

The inherent safety and low cost of aqueous aluminum-air (Al-air) batteries have attracted significant attention. However, their lifespan is constrained due to the formation of passive layers and severe self-corrosion of the Al anode. This work addresses the Al anode issues using an innovative design strategy by adding vanadate and nanoclay to modify the interaction of Al and electrolyte. The results have shown that adding each vanadate, nanoclay, and a hybrid combination of both reduced Al anode corrosion considerably. However, the hybrid additive provided the highest inhibition efficiency of 72.6% compared to 57.6% for vanadium and 69.8% for nanoclay. The anode's anodic efficiency and capacity density reached 81.4% and 2426 mAh.g-1 using a hybrid inhibitor. Electrochemical and microscopical analysis indicated that the corrosion inhibition of the additives was attributed to a protective film formed on the Al anode surface. Therefore, this technique has the potential for application in Al-air batteries to increase their lifespan by increasing the inhibition efficiency of the Al anode.