What is Cyclic Voltammetry? скачать в хорошем качестве

What is Cyclic Voltammetry?

Lets dive into Cyclic Voltammetry with Dr. Lutz Stratmann. Would you like more information about Cyclic Voltammetry: have a look at the PalmSens Knowledgebase: https://www.palmsens.com/knowledgebas.... For an overview of PalmSens potentiostats that support Cyclic Voltammetry, please have a look here: https://www.palmsens.com/product-select/ Transcript: Hello everyone, let's have a look at the most popular electrochemical technique, which is cyclic voltammetry. Let's first have a look at the potential profile that's used to make a cyclic voltammogram. So we start with a linear sweep of the potential. If you're doing it good, you're screening through your formal potential of the species you're interested in. Once you reach a certain potential, the so-called vertex potential, you turn the direction of the scan rate, so the slope of this linear sweep, and then you go back to the potential where you came from. During all of this, you record the current. It might look like something like this. Since it's not very handy to make plots of two curves, usually you make a voltamagram, which is a plot of the current versus the potential. And it looks like this, so you kind of folded the current around, and now it looks like this typical duct shape that you most likely have seen somewhere. Cyclic voltammetry is very popular, because it is very fast. Often the CVs have a characteristic shape that you already have an idea what's going on. The signals you get are quantitative, so you can use it to analyze how much stuff is in your solution. And you can get kinetic information, because you can vary how fast your experiment is with the scan rate. A possible application is the detection of redox mediators. So we're looking for a molecule that can go into an enzyme's active center and take away an electron there, and then bring that to our electrode. And ideally it does that by shuttling between them. So basically we're looking for the last circle on the bottom left. Usually if the complete system is arranged and works, our CV will have a very characteristic shape. Another possible application is the investigation of gold surfaces. So we can make a CV of our gold surface, and while we're moving towards oxidizing potentials, we are oxidizing the gold surface, but only the top layer. Nice property of gold. Then we're going to more negative potentials. Again, the gold gets reduced, we get this very sharp reduction peak that you see here in the CV, and you can use this to find the charge that was used to reduce all your gold. And since in the literature you can find the value for the charge required to reduce a certain area of gold, you can determine this way your real gold area. So this was a quick introduction to cyclic voltammetry. Since it's the most popular technique, of course all our PalmSens instruments can perform cyclic voltammetry. Really all of them. Have a great day, thanks for watching! Chapters: 0:00 Introduction 0:12 Potential profile of a CV: Voltammogram 1:01 Why is Cyclic Voltammetry so popular? 1:25 Possible applications of Cyclic Voltammetry 2:34 Please subscribe to our YouTube channel and find us on LinkedIn   / palmsens-bv