Measuring Temperature-Dependent Thermodynamics of Electrochemical Reactions

Abstract

Temperature is a critical parameter that can significantly influence the outcome of the redox reactions. However, determining the temperature-dependent properties of redox couples is often time-consuming and susceptible to inconsistencies. In this work, we present a temperature-controlled electrochemical station capable of acquiring electrochemical measurements under preprogrammed conditions to extract key thermodynamic parameters. We demonstrate the functionality of this system using electrochemical impedance spectroscopy to determine the activation energies of the [Fe(CN)6]3–/4–redox couple and the hydrogen evolution reaction on platinum and gold electrodes. Additionally, we illustrate automated cyclic voltammetry data acquisition for [Fe(CN)6]3–/4–, [Ru(NH3)6]2+/3+, benzoquinone, and anthraquinone. By analyzing the temperature-dependent shifts in E1/2, we calculated the entropy changes and thermogalvanic coefficients of these systems. Furthermore, we examined the entropy variations of ferricyanide in mixed aqueous–organic electrolytes, highlighting the role of solvation reconfiguration. The versatility of this setup offers a robust and efficient platform for the rapid characterization of temperature-dependent redox properties, with implications for energy conversion and sensing applications.