More Accurate Measurement of Return Peak Current in Cyclic Voltammetry Using Diffusional Baseline Fitting
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| Název: | More Accurate Measurement of Return Peak Current in Cyclic Voltammetry Using Diffusional Baseline Fitting |
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| Autoři: | David Macedo, Theo Rodopoulos, Mikko Vepsäläinen, Samridhi Bajaj, Conor Hogan |
| Rok vydání: | 2024 |
| Sbírka: | La Trobe University (Melbourne): Figshare |
| Témata: | Medical biochemistry and metabolomics, Analytical chemistry, Chemical engineering, Electrical energy transmission, networks and systems, cyclic voltammetry (CV), peak currents, linear baseline, diffusional baseline fitting |
| Popis: | The difficulty associated with accurately measuring the height of the back peak (Ipb) in cyclic voltammetry (CV) has long plagued electrochemists. Most commonly, Ipb is measured by extrapolating a linear fit from a selected region of a voltammogram after the switching potential (Eλ), but without substantial separation between the peak potential (Ep) and Eλ, this approach always overestimates the background current and so underestimates Ipb. Moreover, experimental conditions can present challenges for this method as an appropriate region for linear fitting is often lacking due to neighboring peaks or solvent electrolysis current. Here, we present a new method for finding the baseline current for the back peak in CV experiments. By examining the CV data as a function of time rather than potential, it is possible to fit a generalized Cottrell or Shoup-Szabo equation to the current decay of the forward peak and extrapolate this function as a baseline for the return peak. This approach was tested by using simulated and experimental data in a variety of conditions, including data demonstrating linear and radial diffusional control. We found that the method allows for more accurate determination of back peak currents, especially when linear fits are complicated by narrow electrochemical windows or radial diffusion. A user-friendly Python program was written to automatically find an appropriate fitting range for this analysis and measure peak currents. We have made this program available to the electrochemical community at large. |
| Druh dokumentu: | article in journal/newspaper |
| Jazyk: | unknown |
| Relation: | https://figshare.com/articles/journal_contribution/More_Accurate_Measurement_of_Return_Peak_Current_in_Cyclic_Voltammetry_Using_Diffusional_Baseline_Fitting/25143947 |
| DOI: | 10.26181/25143947.v1 |
| Dostupnost: | https://doi.org/10.26181/25143947.v1 https://figshare.com/articles/journal_contribution/More_Accurate_Measurement_of_Return_Peak_Current_in_Cyclic_Voltammetry_Using_Diffusional_Baseline_Fitting/25143947 |
| Rights: | CC BY-NC 4.0 |
| Přístupové číslo: | edsbas.13AD0A8D |
| Databáze: | BASE |
Nájsť tento článok vo Web of Science | Abstrakt: | The difficulty associated with accurately measuring the height of the back peak (Ipb) in cyclic voltammetry (CV) has long plagued electrochemists. Most commonly, Ipb is measured by extrapolating a linear fit from a selected region of a voltammogram after the switching potential (Eλ), but without substantial separation between the peak potential (Ep) and Eλ, this approach always overestimates the background current and so underestimates Ipb. Moreover, experimental conditions can present challenges for this method as an appropriate region for linear fitting is often lacking due to neighboring peaks or solvent electrolysis current. Here, we present a new method for finding the baseline current for the back peak in CV experiments. By examining the CV data as a function of time rather than potential, it is possible to fit a generalized Cottrell or Shoup-Szabo equation to the current decay of the forward peak and extrapolate this function as a baseline for the return peak. This approach was tested by using simulated and experimental data in a variety of conditions, including data demonstrating linear and radial diffusional control. We found that the method allows for more accurate determination of back peak currents, especially when linear fits are complicated by narrow electrochemical windows or radial diffusion. A user-friendly Python program was written to automatically find an appropriate fitting range for this analysis and measure peak currents. We have made this program available to the electrochemical community at large. |
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| DOI: | 10.26181/25143947.v1 |