Temperature Effect on Silver Electrodeposition in a Deep Eutectic Solvent

Abstract

This work was conducted to determine the influence of temperature of the electrolyte consisting of choline chloride and urea at 1: 2 molar ratio, for silver electrodeposition. Cyclic voltammetry and chronoamperometry analyses were employed to carry out the silver electrodeposition on glassy carbon at 50, 60 and 70 °C. The current density for silver electrodeposition increases with increasing temperature. The description of experimental data through Scharifker and Mostany model, see Figure 1 (a), indicate that the Ag nucleation and growth processes on glassy carbon, regardless of T, are a diffusion controlled processes. The diffusion coefficient, D0, the nucleation rate constant, A, the density of active sites, N0, the work of forming the critical nucleus, ΔG*, and the size of the critical radius, n*, are calculated from experimental data for all temperatures. From SEM images, the morphology of deposited Ag was seen to correspond to a progressive nucleation mechanism, regardless of T, and that the silver concentration in the electrolyte has a significant impact on the nucleation mechanism. Figure 1