Understanding the synergistic effect of alkyl polyglucoside and potassium stannate as advanced hybrid corrosion inhibitor for alkaline aluminum-air battery

An advanced hybrid corrosion inhibitor consisting of alkyl polyglucoside (APG) and potassium stannate (K2SnO3) is proposed to suppress the self-discharge corrosion of the Al anode in an alkaline Al-air battery. The results show that the hydrogen evolution rate with the optimum hybrid inhibitor is significantly decreased from 0.735 ml cm−2 min−1(blank) to 0.043 ml cm−2 min−1 (corresponding to the inhibition efficiency of 94.14%). The discharge mass specific capacity of the full cell with hybrid inhibitor reaches to 2180 mAh g−1, approximately 2.5 times as much as the one with no additive (840 mAh g−1). The significantly reduced hydrogen evolution can be attributed to the synergistic effect of stannate and APG, that is, the hydrophobic segment of APG can regulate the reduction of stannate in the solution system leading to the more uniform and firmer deposition of Sn on the surface of the Al anode. This work can shed some lights on clarifying the corrosion inhibition mechanism of corrosion inhibitors in alkaline Al-air batteries and exploring advanced corrosion inhibitors.