Sciencemadness Discussion Board
Not logged in [Login - Register]
Go To Bottom

Printable Version  
Author: Subject: Square Wave Voltammetry Simulation
smaerd
International Hazard
*****




Posts: 1262
Registered: 23-1-2010
Member Is Offline

Mood: hmm...

[*] posted on 25-12-2015 at 18:11
Square Wave Voltammetry Simulation


Because, I always thought electrochemistry was Oh-So-Fascinating I learned some of it's basic principles/applications. Interestingly electrochemistry is one of the types of chemistry which can be modelled quite easily and 'well' via simulation. One of my favorite applications is Square-wave Voltammetry (SWV). .

In the holiday spirit I figured I'd share some code with you all :).

Here's a SWV simulation function written in R which I adapted from a publication written in MATHCAD (Bulletin of the Chemists and Technologists of Macedonia, Vol. 18, No. 1, pp. 57–64 (1999)). Keep in mind this simulation is not the complete story and exhibits a good deal of simplifications/approximations but it's good enough to get the ball rolling.

Attachment: square.wave.R (3kB)
This file has been downloaded 124 times

I am also including a few small examples which demonstrate how the function can be used. The first uses the same kinetic parameters except changing diffusion based mass transfer (diffusion constant) in situations of say increasing binary solvent concentration.

Attachment: diffusion tests2.R (845B)
This file has been downloaded 120 times diffus sim kinda small.png - 5kB

The second examines the effect of charge transfer coefficient (α) and heteregeneous rate constant (k) on peak current. This is a simple theoretical way to try to find scan-rates that will produce quantitative data from peak current (height) in many samples with different environments/conditions.

For the uninitiated this simply means that the kinetic parameters (α, k) both change the observed peak height(amps) for a given analyte. Interestingly, these parameters are also effected by the scan rate (volts/second). So if there is a range of kinetic parameters where the peak current is effectively constant (flat) then the scan rate which induces the kinetic parameters to be in the constant "domain" is ideal for use to obtain quantitative information.

Attachment: K and alpha variance on current.R (3kB)
This file has been downloaded 111 times small sim plot.png - 6kB


Anyway, hope this helps someone out. It was fun doing it. Be kind, R is not my native language but it is free and widely available for all operating systems. Feel free to modify and use the code but do include the reference(my code is VERY SIMILAR to that of the mentioned article).

There are a few small hiccoughs in the code. I am sure of that :). Again, feel free to modify, improve, adapt, and upload changes or interesting uses for it.

[Edited on 26-12-2015 by smaerd]

[Edited on 26-12-2015 by smaerd]




View user's profile View All Posts By User

  Go To Top