EQCM Study on Electrochemical Zinc Deposition-Dissolution in Water-In-Salt Electrolyte

Abstract

The reversible deposition-dissolution reactions of zinc in several “water-in-salt” (WIS)-based electrolytes were monitored and compared using an electrochemical quartz microbalance (EQCM). These WIS electrolytes, irrespective of composition, promote reversible zinc deposition with high Coulombic efficiency. The mass change on the electrode, the local viscosity, and the change in the water content differ among electrolyte compositions, possibly because of phase separation to a solid zinc salt-water precipitate induced by the local concentration change of electrolyte during zinc dissolution.

Keywords

• electrochemical quartz microbalance
• water-in-salt electrolyte
• zinc deposition