guest ::
| Home > Publications database > In-Situ electrochemical mapping of local activity on Zn and Zn-Al alloy using scanning electrochemical microscopy |
| Home > Publications database > In-Situ electrochemical mapping of local activity on Zn and Zn-Al alloy using scanning electrochemical microscopy |
| Poster (After Call) | FZJ-2024-00086 |
; ; ; ; ;
2023
Abstract: Metal-air batteries have gained tremendous attention in the past years as promising technologies due to their theoretically high specific energy and environmentally friendly use of oxygen 1. Considering the cost-effectiveness and natural abundance, Zn and Al are good candidates for metal-air batteries. However, in Zn-air systems, stable cyclability is an issue due to the passivation layer on Zn electrodes in neutral electrolyte. Guerrero et al. reported recently that ethylenediaminetetraacetic acid (EDTA) as an electrolyte additive activates the surface of Zn electrode to maintain metallic property, thereby improving the performance of Zn-air batteries in near-neutral chloride-based electrolyte 2. In this study, we investigate the local activity on Zn and Zn-10Al alloy electrodes in 2 M NaCl (pH 10) containing EDTA by using scanning electrochemical microscopy (SECM). We observed that the surfaces of Zn and Zn-10Al alloy electrodes are passivated at open circuit potential (OCP) and these passivation layers disappear at OCP by adding EDTA in the electrolyte. As the potential is applied to slightly positive of OCP, the formation of the passivation layer is more dominant than the activation by EDTA, resulting from the limited amount of dissociated EDTA in near-neutral electrolyte. It is noteworthy that a clear topographic change is observed by means of AFM-SECM after the electrode contacts with EDTA, which demonstrates the effect of EDTA.
|
The record appears in these collections: |