Understanding the Electrochemical Deposition Process of Silver Metal

Abstract

While lithium metal anode has been intensively studied in recent years, the unavoidable formation of solid electrolyte interphase (SEI) layers on Li surface implicates the fundamental understanding of the origin of uneven Li deposition driven by over potentials 1. Unlike Li, Ag has a very clean surface in contacting with the liquid electrolyte2 providing a good platform to study the mass transport process of metal cations in the solution phase and how they affect the final morphologies of Ag deposited. The effects of current density, and concentration of cation species on silver metal deposition firstly investigated and correlated to the various crystalline structures of Ag plated. Then different anions are added in the electrolyte to further understand how the coordination environments of Ag+ change in the presence of different anions and their impacts on the nucleation and growth process of Ag particles. A microelectrode was applied to measure the kinetic parameters such as diffusion coefficient and limited current density in different electrolytes. The kinetic and thermodynamic mechanisms governing the observed morphological changes in the deposited silver material will provide new insights for understanding the more complicated system such as Li deposition and inspire new solutions to fundamentally control the cation transport to realize the final morphology control of the electrochemically deposited metals. References Zhang, S. S. Problem, Status, and Possible Solutions for Lithium Metal Anode of Rechargeable Batteries. ACS Appl. Energy Mater. 1, 910–920 (2018).Suo, L. et al. “Water-in-salt” electrolyte enables high-voltage aqueous lithium-ion chemistries. Science 350, 938 (2015).