Regulating the Anode Corrosion by a Tryptophan Derivative for Alkaline Al–Air Batteries
Yue Huang, Lei Guo, Qiao Zhang, Wei Shi, Wei Feng, Faheem Abbas, Xingwen Zheng, Senlin Leng, Yujie Qiang, Viswanathan S. Saji
Abstract
Screening a green corrosion inhibitor that can prevent Al anode corrosion and enhance the battery performance is highly significant for developing next-generation Al–air batteries. This work explores the non-toxic, environmentally safe, and nitrogen-rich amino acid derivative, N (α)-Boc- l -tryptophan (BCTO), as a green corrosion inhibitor for Al anodes. Our results confirm that BCTO has an excellent corrosion inhibition effect for the Al-5052 alloy in 4 M NaOH solution. An optimum inhibitor addition (2 mM) has increased the Al–air battery performance; the corrosion inhibition efficiency was 68.2%, and the anode utilization efficiency reached 92.0%. The capacity and energy density values increased from 990.10 mA h g –1 and 1317.23 W h kg –1 of the uninhibited system to 2739.70 mA h g –1 and 3723.53 W h kg –1 for the 2 mM BCTO added system. The adsorption behavior of BCTO on the Al-5052 surface was further explored by theoretical calculations. This work paves the way for constructing durable Al–air batteries through an electrolyte regulation strategy.