Bridging the gap between ab initio simulations and experiments through EIS

Abstract

We have developed an analytical solution to compute the impedance spectra using ab initio parameters such as total Gibbs free energy change for the electron transfer reaction, reorganization energy, activation energy, and occupied energy levels in the electrode. The impedance model is developed to relate DFT computed parameters to experiments using Electrochemical Impedance Spectroscopy (EIS) using the analytical solution of the Marcus-Hush-Chidsey (MHC) reaction rate theory developed by Zeng et al. (Y. Zeng, R.B. Smith, P. Bai, M.Z. Bazant, “Simple formula for Marcus–Hush–Chidsey kinetics”, J. Electroanal. Chem. 735 (2014) 77–83.). Next, we compare the reaction rates computed by Butler-Volmer and MHC theory and impedance responses using the two reaction models. Finally, we provide a few analytical predictions of our analytical model using the MHC theory