Influence of Micrometric-Scale Electrode Heterogeneity on Electrochemical Impedance Spectroscopy

Christopher L. Alexander (1) , Bernard Tribollet (2) , Mark E. Orazem (1)

1 UF|CHE - Department of Chemical Engineering [Gainesville]
2 LISE - Laboratoire Interfaces et Systèmes Electrochimiques

Numerical simulationsforadiskelectrodeshowthatthefrequencyatwhichtime–constantdispersion appears dependsonthecharacteristicdimensionofthefeaturecausingthedispersion.Thecharacter- istic dimensionforadiskistheradius;forroughness,itisafunctionofrugosityandtheperiodof the roughness;andforacapacitancedistribution,itistheperiodofthedistribution.Distributionsof charge–transfer resistancedonotcausetime–constantdispersionbecausetheyinfluenceneitherthe ohmic resistancenorthecapacitance.Asonlythehigh–frequencyimpedanceisaffectedbyroughness and capacitydistributionsandcharge–transferresistancedistributionsdonotcausefrequencydisper- sion, surfaceheterogeneityintheformofroughness,capacitance,orcharge–transferresistancecannot provide anexplanationforCPEbehaviorassociatedwithsurfacedistributions.

Mots clés: Frequency dispersion; capacitance; impedance spectroscopy

Domaines: Chimie; Autre

Christopher L. Alexander, Bernard Tribollet, Mark E. Orazem. Influence of Micrometric-Scale Electrode Heterogeneity on Electrochemical Impedance Spectroscopy. Electrochimica Acta, 2016, 201, pp.374 - 379. ⟨10.1016/j.electacta.2016.02.133⟩. ⟨hal-01402265⟩