A connection between anomalous Poisson-Nernst-Planck models and equivalent circuits with constant--phase elements

TL;DR

This paper establishes a theoretical link between anomalous Poisson-Nernst-Planck models and equivalent circuits with constant phase elements, explaining surface effects in electrolytic cells and validating predictions with experimental data.

Contribution

It introduces a novel connection between PNPA models and CPE-based circuits, enhancing understanding of impedance responses in electrolytic systems.

Findings

CPE can replicate anomalous diffusive effects in impedance spectra

The model aligns with experimental data from electrolytic solutions

Surface effects are linked to circuit elements in low-frequency limit

Abstract

A connection between the impedance spectroscopy response of anomalous Poisson-Nernst-Planck (PNPA) diffusional models and of equivalent circuits containing constant phase elements (CPE) is established for a typical electrolytic cell. The analysis is carried out in the limit of low frequency in order to highlight the surface effects and to explore how they can be connected to the presence of CPE in the circuit. It is shown that, depending on the choice of the equivalent circuit, the action of these elements can be the same as the one obtained by using integro-differential boundary conditions to describe anomalous diffusive processes in the framework of PNPA models. The predictions are also compared with an experimental data obtained from an electrolytic solution.