A one-dimensional stochastic approach to the study of cyclic voltammetry with adsorption effects

Abstract

In this study, a one-dimensional stochastic model based on the random walk approach is used to simulate cyclic voltammetry. The model takes into account mass transport, kinetics of the redox reactions, adsorption effects and changes in the morphology of the electrode. The model is shown to display the expected behavior. Furthermore, the model shows consistent qualitative agreement with a finite difference solution. This approach allows for an understanding of phenomena on a microscopic level and may be useful for analyzing qualitative features observed in experimentally recorded signals.

What X‐Ray Absorption Spectroscopy Can Tell Us About the Active State of Earth‐Abundant Electrocatalysts for the Oxygen Evolution Reaction**

“…The peak potential of adsorption/desorption processes depends on the concentration of the involved ion in solution, which can be used for their identification [22] . On metal oxides, adsorption/desorption without a redox process is rarely discussed, likely due to localized electronic states [54–58] . Furthermore, different surface facets may have different reaction energies of the same element and thus two anodic peaks do not necessarily indicate redox of two different elements [59–61] .…”

“… [22] On metal oxides, adsorption/desorption without a redox process is rarely discussed, likely due to localized electronic states. [ 54 , 55 , 56 , 57 , 58 ] Furthermore, different surface facets may have different reaction energies of the same element and thus two anodic peaks do not necessarily indicate redox of two different elements. [ 59 , 60 , 61 ] Likewise, one broad peak or shoulder does not necessarily correspond to a single redox reaction but instead may correspond to several redox reactions.…”

What X-ray absorption spectroscopy can tell us about the active state of earth-abundant electrocatalysts for the oxygen evolution reaction

“…13 On metal oxides, adsorption/desorption without a redox process is rarely discussed, likely due to localized electronic states. [45][46][47][48][49] Furthermore, different surface facets may have different reaction energies of the same element and thus two anodic peaks do not necessarily indicate redox of two different elements. [50][51][52] Likewise, one broad peak or shoulder does not necessarily correspond to a single redox reaction but instead may correspond to several redox reactions.…”

Was uns die Röntgenabsorptionsspektroskopie über den aktiven Zustand von Elektrokatalysatoren für die Sauerstoffentwicklungsreaktion lehrt**

“…[22] Auf Metalloxiden wird Adsorption/Desorption ohne Redoxprozess nur selten diskutiert, was wahrscheinlich auf lokalisierte elektronische Zustände zurückzuführen ist. [54][55][56][57][58] Außerdem können verschiedene Oberflächenfacetten unterschiedliche Reaktionsenergien desselben Elements aufweisen, so dass zwei anodische lokale Extrempunkte nicht unbedingt auf Redoxreaktionen von zwei verschiedenen Elementen hinweisen. [59][60][61] Ebenso entspricht ein breiter lokaler Extrempunkt oder eine breite Schulter nicht unbedingt einer einzigen Redoxreaktion, sondern kann auf mehrere Redoxreaktionen zurückzuführen sein.…”