A Theoretical Framework for the Electrochemical Characterization of Anisotropic Micro-Emulsions

TL;DR

This paper develops a theoretical framework for electrochemical characterization of anisotropic micro-emulsions using cyclic voltammetry, incorporating spatially dependent diffusion and complex reaction schemes.

Contribution

It introduces a modified diffusion equation for anisotropic MEs and an extended numerical scheme for kinetically controlled reactions, validated by experimental data.

Findings

Validated theoretical model with experimental CV data.

Captured anisotropic diffusion effects in electrochemical analysis.

Provided a quantitative method for characterizing micro-emulsions.

Abstract

Micro emulsions (MEs) offer an exceptionally broad spectrum of applications covering sensing, electrosynthesis, supercapacitors and redox-flow batteries. Herein, we develop the theory for a sophisticated electrochemical characterizion of MEs with a spatially and time-invariant anisotropy in the diffusion domain by means of cyclic voltammerty (CV). By introducing spatially dependent diffusion coefficients into Ficks' first law, we derive a modified diffusion equation to simulate any inherent anisotropy of the ME under investigation. Moreover, by formulating an extended second-order homogeneous six-member square scheme for a kinetically controlled two-step two-electron reaction we capture the intricate entanglement of chemical and electrochemical equilibria. Our theoretical concept is finally validated by experimental CV data for the ME based two-step redox reaction of methyl-viologen which paves the way for a quantitative electrochemical characterization MEs.