Simulation-Based Approach to Determining Electron Transfer Rates Using Square-Wave Voltammetry

Philippe Dauphin-Ducharme, Netzahualcóyotl Arroyo-Currás, Martin Kurnik, Gabriel Ortega, Hui Li, Kevin W. Plaxco

Research output: Contribution to journalArticlepeer-review

Abstract

The efficiency with which square-wave voltammetry differentiates faradic and charging currents makes it a particularly sensitive electroanalytical approach, as evidenced by its ability to measure nanomolar or even picomolar concentrations of electroactive analytes. Because of the relative complexity of the potential sweep it uses, however, the extraction of detailed kinetic and mechanistic information from square-wave data remains challenging. In response, we demonstrate here a numerical approach by which square-wave data can be used to determine electron transfer rates. Specifically, we have developed a numerical approach in which we model the height and the shape of voltammograms collected over a range of square-wave frequencies and amplitudes to simulated voltammograms as functions of the heterogeneous rate constant and the electron transfer coefficient. As validation of the approach, we have used it to determine electron transfer kinetics in both freely diffusing and diffusionless surface-tethered species, obtaining electron transfer kinetics in all cases in good agreement with values derived using non-square-wave methods.

Original languageEnglish (US)
Pages (from-to)4407-4413
Number of pages7
JournalLangmuir
Volume33
Issue number18
DOIs
StatePublished - May 9 2017
Externally publishedYes

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Surfaces and Interfaces
  • Spectroscopy
  • Electrochemistry

Fingerprint Dive into the research topics of 'Simulation-Based Approach to Determining Electron Transfer Rates Using Square-Wave Voltammetry'. Together they form a unique fingerprint.

Cite this