Electrochemistry Tools
A collection of experimental and analytical tools for conducting molten salt electrochemistry work
Cyclic (or linear sweep) Voltammetry Models
Soluble-Insoluble Reactions
Electrodeposition is a common soluble-insoluble reaction. A few models for calculating a couple properties are available at the github links below.
This model simulates the cyclic voltammetry response of an electrodeposition reaction in molten salts. It accounts for uncompensated resistance, semi-infinite linear diffusion, migration, adsorption (deposition onto a foreign substrate), and activity effects of dissolved analytes. It is currently under development to account for radial diffusion and natural convection. Additional effects, such as kinetics and surface area growth, will also be implemented, but will require longer developmental times.
Two files are provided in the repository linked above. One uses the solver, and the other uses a macro. Descriptions of each file are provided in the linked repository. These files account for the activity effects encountered when depositing onto a foreign substrate and/or using a digital staircase instead of a true linear (analog) scan for reversible reactions. However, it does not account for uncompensated resistance.
Standard Apparent (or Formal) Potential
The linked file can be used to calculate the standard apparent potential from the peak potential of cyclic voltammetry reduction peaks correlated to the deposition of metal onto a foreign substrate. The model assumes semi-infinite linear diffusion and reversible soluble-insoluble reactions. The model accounts for: (1) reversible reactions, (2) deposition onto a foreign substrate, (3) digital staircase instead of a true linear scan, and (4) uncompensated resistance.
The linked file above estimates the uncompensated resistance present in a cyclic voltammetry measurement based on the peak potential. Uncompensated resistance can distort measurements by shifting the peak potential and suppressing the peak. The model assumes semi-infinite linear diffusion and reversible soluble-insoluble reactions. The model accounts for: (1) reversible reactions, (2) deposition onto a foreign substrate, (3) digital staircase instead of a true linear scan, and (4) uncompensated resistance.
The linked file above estimates the uncompensated resistance in a square wave voltammetry (SWV) measurement based on the "back-half" peak width of the SWV peak. For more details, see Fuller et al. (2022) A comparison of square-wave voltammetry models to determine the number of electrons exchanged in metal deposition. Electrochimica Acta, 414, 140220. https://doi.org/10.1016/j.electacta.2022.140220 or Accepted Manuscript. Be sure to verify that you meet the requirements on the "Introduction" tab of the spreadsheet after downloading.
Experimental Tools
Conversion from Ag/AgCl to Cl-/Cl2 reference potentials
This file uses the most reliable data from the literature to compare and convert between the Ag/AgCl reference electrode and the Cl-/Cl2 reference electrode in eutectic LiCl-KCl melts
This tool can be used to determine the amount of each salt constituent to add to achieve a eutectic mixture of LiCl-KCl and to achieve a certain wt% of analyte(s) within the eutectic LiCl-KCl melt
This tool estimates the standard reduction potential from thermodynamic data. It has been specifically designed for high-temperature molten salts. Some thermodynamic data is preloaded. However, the user may need to add additional data for their specific species. This assumes a pure reference state (i.e., mole fraction of 1). If the species is dilute, the equilibrium potential may vary significantly from E0. This is a simple estimation tool and doesn't calculate the hypothetical supercooled liquid reference state when estimating standard potentials. This may introduce some error on the order of 10-100 mV. However, it can give a good approximation when standard potentials are unknown.