*Summary* *Intro* - *0:02**:* [Music] - *0:10**:* Introduction to the video on Electrochemical Impedance Spectroscopy (EIS). - *0:18**:* Acknowledgement of EIS's complexity and the video's introductory nature. - *0:38**:* Overview of the video structure, covering EIS components, data generation, and application. *What is Electrochemical Impedance Spectroscopy?* - *1:29**:* Explanation of EIS as a technique using potentiostats to apply and measure sinusoidal potentials/currents in electrochemical systems. - *1:50**:* Distinction between potentiostatic and galvanostatic EIS. - *2:10**:* Characteristics of the sinusoidal potential applied and the corresponding output current. - *2:57**:* Concept of phase shift or angle in EIS. - *3:09**:* Procedure of conducting EIS experiments across multiple frequencies. *Fourier Transform and what Impedance is* - *3:36**:* Use of Fourier transform to convert time-domain data to frequency-domain. - *4:00**:* Comparison of impedance calculation in EIS with Ohm's law in DC circuits. - *4:39**:* Definition of impedance in the context of alternating currents or potentials. - *5:00**:* Impedance as a measure of anything that impedes electron flow. *The Bode Plot* - *5:17**:* Introduction of the Bode plot from EIS data, showing impedance magnitude and phase angle. *The Nyquist Plot* - *5:48**:* Conversion of Bode plot data to Nyquist plot using cartesian coordinates. - *6:03**:* Explanation of real and imaginary impedance in Nyquist plot. *Analogy for understanding EIS* - *7:09**:* Use of a symphony analogy to explain how EIS discerns different electrochemical phenomena at characteristic frequencies. *Why use EIS?* - *8:24**:* EIS's ability to probe different electrochemical phenomena at specific frequencies. - *9:01**:* Contrast between EIS and other electrochemical techniques like DC voltammetry in analyzing concurrent processes. *How EIS data is used (modeling an electrochemical system)* - *10:09**:* Modeling complex electrochemical phenomena using circuit elements. - *11:03**:* Combination of qualitative and quantitative analysis in EIS through circuit fitting and software. *Conclusion* - *12:01**:* Acknowledgment of EIS's complexity and a call for viewers to stay tuned for more in-depth content.
I have been doing EIS this week and wanted a clear explanation of EIS basics. This video helped me understand and interpret my data. Thank you very much! Great help!
Thank you so much for this wonderful explanation. I've been trying to make sense of nyquist plots for some time now and none of the websites I visited made it this simple and clear.
We appreciate the comment, glad it was helpful for you! I think making sense of EIS data is a lifelong task, to be honest I'm not sure it ever completely makes sense! :D
We are glad you liked it! I would also say that university professors can get caught up in the weeds of the technique, but we prefer a simpler and more accessible approach to the technique :)
It was 12 minutes of pleasure, simple clear and easy explanation of eis. Please keep entertaining us with electrochemical technics especially those applied for electrocatalysis and rechargeable batteries…
EIS is probably one of the most complex areas of electrochemistry, and electrochemistry itself is pretty complex. We tried to make the introduction to the field as easy to understand as possible. But it will take some time and experimentation to really understand it. Thanks for watching!
I need video explaining how to use eis and which test I should select. I have like 8 option in my system. I'm confused and also how u determine if the same has high or low corrosion resistant from z real zcimag graph. I saw all your video but non explain what is the data mean in that I get. Thank you so much
I'm glad you enjoyed the video. It's one thing to understand EIS conceptually, it's another to do it on a real system and understand what it means. We have a bunch of other videos on EIS that go into more details, for example, our video on EIS of coated steel corrosion ua-cam.com/video/Ov1KKDWLq0s/v-deo.html
Pine Research's AfterMath software is free to download (you just need to make a free account) and it has EIS circuit fitting. We also have some tutorials on circuit fitting on our UA-cam channel. pineresearch.com/shop/kb/knowledge-category/software/
Thank you so much. These topics are so crucial for electrochemical research but seldom explained to this level of clarity.Waiting for more such educational videos..
@@ayushisinghal1379 Hello Ayushi. Two semi circles means that you have two Randles circuits (resistor and capacitor in parallel) in series. Physically, your electrochemical system has at least two interfaces. Does this make sense? We have free circuit simulation software you can download off our website pineresearch.com/shop/kb/knowledge-category/downloads/ You just need to create an account, but then you can download AfterMath software and under the Analysis/Tools select circuit simulation. You can then see what the Nyquist plot with two Randles circuits in series look like and how the two semi-circles change. I hope this helps.
@@ayushisinghal1379 Another resource that might help is our knowledgebase article pineresearch.com/shop/kb/theory/eis-theory/eis-basics/ Section 3 in particular goes into circuit fitting and the Randles (RC) circuit. The article only describes the simple case of one semi-circle however. If you have two RC circuits in series you would get two semi-circles, using the same logic described for the one semi-circle case.
I have questions please, what is the point of doing model for EIS ? Do the circuit represent the electrochemical reaction so basically we can use it as model for our system????
Your exactly right. EIS data by itself isn't very useful, it's only useful when you use it to model an electrochemical system, using the circuit elements as parts of your system.
In reality there are some special transformations a potentiostat/software does to calculate the phase shift. However, you are correct, the phase shift can be thought of as the time delay between the input and output max amplitudes. But it's also the delay between every other point as well. The maximum amplitude is the easiest to visualize when it comes to visualizing the phaseshift. Remember, that both input and output signals must have the same frequency for it to be impedance. I hope this helps.
Thank u for providing such a knowledgeable and important video in free of cost. The way you explained everything, is really comprehensible. NeverthIess, I have one question regarding this EIS, I hope You will address my doubt. I have seen a video in you tube where Mott Schottkey plot was done from EIS data. I have used the same method to plot Mott Schottkey from EIS, but in EIS data, no potential data column was given, which is required to plot Mott Schottkey, instead a frequency column was given. I want to know if you have any idea how EIS data can be used to plot Mott Schottkey. Thank u
Thank you for your kind words. I'm no expert at Mott-Schottky, my colleague Dr. Neil Spinner prepared the advanced EIS webinar on the topic. But you are correct, Mott-Schottky requires a column of potential data as well to perform the analysis. What that means is you will need to perform EIS experiments centered around multiple potentials. So it's a fairly long experiment. Does that make sense?
The impedance itself is the resistance, so if you are studying a corrosion inhibitor you should observe a large increase in the resistance when the inhibitor is added. But most people study corrosion using techniques like linear-polarization resistance (LPR) which gives you things like the corrosion rate.
We appreciate your comment and watching our video! If you have more questions you want to ask us, feel free to join one of our Livestreams on Fridays at 1pm EST, we try to answer electrochemistry questions every week.
Thank you for your explanation, I finally understood the basics. But can I calculate the solution resistance without a programm? I can measure all important values but I don’t have an analysis programm. Thank you!
I am not sure exactly what you mean by "without a program." If you have an instrument capable of performing EIS, then you should be able to calculate the solution resistance, yes, even if you do not have software that automatically displays the result for you. All you need to do is perform an EIS experiment over a few decades of high frequency (i.e., 100 kHz to 1 kHz will likely be sufficient), then obtain a reasonable estimate one of two ways: first, on the Nyquist plot you can find the point closest to the x-axis (where the y-axis -Zim value is smallest) and take that corresponding Zreal value to roughly be equivalent to the solution resistance. The second method would be to use the Bode plot and take the corresponding |Z| value where the phase angle is closest to zero. Either will likely give you a similar value and should be equivalent to the solution resistance.
You answered my question perfectly, thank you! Will the measurement change my solution or can I reuse it for other measurements like CV or EIS at a different temperature?
@@NadineLachmann One of the great things about EIS is that it is fundamentally non-invasive, so almost certainly the measurement itself should not impact your solution, no. That means you should be able to measure the solution resistance and then use it for subsequent experiments. However, I should be clear that if you change the temperature, it may have an effect on the solution resistance. I suggest you measure and use the solution resistance value unique to each temperature you wish to conduct further experiments at, whether CV or EIS.
That‘s exactly what I want to do! I want to determine the solution resistance for three different temperatures to get a better understanding of my system! Thank you so much!😊
We have a bunch of advanced EIS videos from our webinars. I would also recommend checking out our free webinars we offer. We are actually offering a 5-part EIS webinar starting February 2nd. pineresearch.com/webinar-registration/ This would give you a deeper dive into EIS.
Analyte, cation, anion, and solvent are the chemicals used in an electrochemistry experiment. The solvent is usually the liquid like water, acetonitrile, dimethyl sulfoxide, etc. The cation and anion make up the salt that is added to the solvent. So a salt like NaCl, would dissolve in the solvent forming Na+ and Cl-. Na+ is the cation and Cl- is the anion. The analyte is the generic term for the molecule you are studying. I hope this makes sense.
Hello sir, we perform EIS experiments on our own potentiostate (CH instrument). Is your webinar going to be helpful for our EIS data analysis or is that solely for pine research instruments ?
Out 5-part EIS webinar series is general for EIS and can be useful for anybody trying to learn EIS regardless of the potentiostat they use. For parts of the webinar that go over circuit fitting, we will be using Pine Research's AfterMath software to perform the circuit fitting. But you can use other software to perform circuit fitting. I hope this was helpful.
Thank you so much for such a video full of knowledge and explain in such a simple way. I hope to see more videos in this regard specially on EIS of ceramic electrolyte and how EIS help us to find bulk resistance, grains and grain boundaries resistance, charge transfer resistance and warber. and also stay connected with you guys.
Thank you for your good explanation. Recently I was figuring out how to use EIS to calculate the diffusion coefficient. In many literatures the researchers just simply carried out a EIS test and then used the equation D=(R^2*T^2)/(2A^2*n^4*F^4*C^2*σ^2). I feel confused about what is semi-infinite diffusion, the physical meaning of warburg coefficient, in what circumstances can I use the equation. What is the differences between soluble analyte (analyte diffusion) and solid analyte (counter ion diffusion)? Maybe too many questions haha.
I completely understand. These are great questions, and might be a bit too much to address in a single UA-cam comment. Shameless plug aside, Pine Research is offering a free EIS webinar series pineresearch.com/eis-webinar-series-registration/ it's run by my colleague Dr. Neil Spinner, and I think you'd get a lot out of it. To address questions about warburg coefficients, semi-infinite diffusion, etc he will probably talk about those in the later parts of the series (part 3, 4, and 5). However, I would encourage you to attend the whole thing. I hope this was helpful.
We use AfterMath Blue, which is Pine Research's software. AfterMath Blue is free, but to do circuit fitting it will require a paid license. Let me know if you are interested.
I want to know the separarion of double layer capacitance and pseudocapacitance by analysing the nyquist plot..the value of specific capacitance..plz suggest.
To be honest, I'm not sure there is an effective way to perfectly distinguish using EIS data between Cdl and pseudocapacitance. My best guess would be that perhaps you can fit with a constant phase element (CPE) and monitor the value of α you get. Perhaps a value that indicates severe non-ideality (something like 0.6-0.8, for example) could be a marker for non-ideal capacitance or pseudocapacitance. But this is more of an educated guess as to how you might make that distinction, since as I noted I am not 100% certain EIS data can easily help you analyze and differentiate between those two phenomena.
@@surajittalukdar5536 It is my pleasure. You can comment any time, we check our UA-cam comments every day and always make efforts to reply. You can also join us on Fridays at 1pm EST for our weekly Livestreams if you like and want to ask any questions that we can answer for you live. It is a little more interactive than the comments section I think :)
Plotting negative Zimaginary is mostly a convenience thing. For most systems the imaginary impedance is negative, so we would be able to plot data in the 1st quadrant rather than the 3rd in a graph. But fundamentally, negative imaginary impedance comes from capacitive processes, the impedance of a capacitor is -j/wC. So the negative sign is just part of the equation.
The beauty of EIS is that there isn't necessarily a total resistance, but a resistance measured across different frequencies. The total resistance by itself isn't as useful. I suppose my question to you is, what is your system and what does the total resistance mean?
Time scale (at least in this context) refers to something that oscillates, so we are talking about the frequency of a repeating motion. Imagine two separate wheels that are spinning. One is spinning at 1 mph, the other is spinning at 100 mph. The frequency or time scale of the two wheels are very different. If I marked both wheels with yellow paint I could easily watch the yellow mark on the wheel spinning 1 mph. But it would appear as a blur if I watched the 100 mph wheel. Both wheels are spinning at the same time, but I can only detect the motion of the 1 mph wheel. Does this help?
Hello, Good morning, I appreciate the knowledge shared on this channel. Studying about the EIS technique I have a doubt that I have not yet been able to solve clearly, the question is What does it mean that a material has its phase angle at lower or higher frequencies than another material? In which of these cases would there be a higher resistance to corrosion?
Hello Jose, thanks for your question. First of all, I want to clarify that when you write "...material has its phase angle..." I assume you are referring to a kind of graphical dip in the phase angle on the Bode plot that is observed for features that are often fitted with a Randles circuit. If this is the case, then the simplest answer I can give you (neglecting all other processes that might be occurring on your materials of interest) is that the phase angle peak is related to the capacitance and the time constant. To elaborate just a little bit: if the capacitive effects being observed are very small, it means it can be charged/discharged very rapidly, meaning the peak will manifest at higher frequencies. Conversely, if the capacitive effects are very large, it will take longer, or be slower, for the charge/discharge phenomena to occur, meaning the phase peak will appear at lower frequencies. All of the above is also neglecting the resistance, which can also have an effect on where the phase angle peak appears; and on the time constant, which is a pseudo-measurement of how long this charge/discharge process takes. Finally, to address your question about corrosion resistance: the position of the peak *may* give insight into the corrosion resistance, but not necessarily. For example, following the previous discussion on capacitance: if the phase angle peak is at high frequency, it likely implies lower capacitance and a somewhat smaller time constant, which could also imply a smaller resistance. But it is not guaranteed that is the case. You can have a large resistance even with a small time constant if the capacitance is just extremely small. Conversely, a phase angle peak at low frequency might imply higher capacitance and a larger time constant, which could imply a larger resistance; but again, this is not guaranteed because you could still have a small resistance even with a large time constant. This is because the time constant is equal to R times C, so a proper circuit fitting analysis would likely be required to reveal whether your material is exhibiting high or low corrosion resistance.
I need a little more clarification on the data and modeling you are interested in. Usually, impedance is not plotted or measured with respect to current. You typically get Nyquist and/or Bode plots which plot the real impedance vs negative imaginary impedance (Nyquist), or the impedance magnitude and phase vs the frequency (Bode). I suppose the question is, what exactly to you want to do?
@@Pineresearch sorry, I was wrong these are typical data z' vs. z''. I got just an excel with the datas and dont have access to silulation software. Need help.
@@WolfdietrichMeyer You can use our AfterMath software to do circuit fitting. It can't be downloaded for free off our website. You only need to create an account (also free) on the website, to download it. pineresearch.com/shop/kb/knowledge-category/downloads/ Once you have AfterMath on your computer under File--> Import External Data you can import a CVS file of your EIS data. Let me know if you need additional clarification. I hope this helps.
I'm happy to hear that. We've got some Advanced EIS Webinars and circuit fitting UA-cam videos that might be helpful for whatever system you are looking to characterize.
I can only speak on behalf of Pine Research, but our AfterMath software performs K-K analysis to validate your EIS data. If you are using another potentiostat you can important your data to AfterMath, and there is an option to perform K-K. Then you can look at how well the fit is and the chi-squared value to see if you EIS data is valid. You can download AfterMath for free and use our circuit fitting and K-K analysis tools. All you need to do is create a free account on our website. pineresearch.com/shop/knowledge-category/downloads/
Thank you so much. Please help me with another query. What is the acceptable chi-squared value for EIS data in KK analysis. I have EIS data that gives 0.0008 chisq value. Is the data valid?
@@yeasmins074 The problem with judging a fit by chi squared is that there is not an easy universal metric to gauge whether it is good or bad. Whether you are doing circuit fit or K-K analysis, chi squared should generally be used as a comparison across multiple analyses on the same data. For K-K in particular, it is both quantitative through chi squared but also extremely subjective. You may have to determine for yourself how closely the fit appears to match your data and make a determination from there. You may also find, for instance, some frequencies fit better than others. Sometimes the low frequency points don't match as well because of drift, but the mid to high frequency points do, so you can propose most of your data are valid but the lower frequencies are less accurate. But overall, it is not simple to give a set universal chi squared metric for saying definitively something like "larger = bad, smaller = good"
@@Pineresearch Yes, and at the same time I am talking about: how the electrical components e.g., resistor, capacitor and inductor can be shown by the diagram in schematic. You have shown & explained the circuit diagram at the end but I would like to know the whole process including all components in one diagram.
@@tanzilanurjahan6609 Well first, I would recommend watching our "How a potentiostat works" video ua-cam.com/video/pzB122dTij8/v-deo.html But regarding the circuit elements of how a potentiostat works with regard to EIS I cannot provide you with a circuit diagram. First, there are proprietary reasons and second, it's too complex for one diagram. But the key takeaway with regard to how a potentiostat works from an EIS perspective, is that the potentiostat requires what is called an FRA (Frequency response analyzer). This allows your potentiostat to take in AC signals (necessary for EIS). Are you trying to build an EIS capable potentiostat from scratch?
@@tanzilanurjahan6609 You're welcome. I think the best way to understand the circuit is to check out the video I mentioned before about how a potentiostat works. This will help you understand how a potentiostat maintains a set potential and measures the current response. You can then think of the potentiostatic setpoint (from the circuit in that video) as the waveform generator for producing a sine wave. And subsequently, you can think of the E/I voltmeter which allows us to indirectly measure the current, as a way to measure the sinusoidal current response. Then you do all the calculations performed in this video.
Thank you Luiz! Actually, Dr. Neil Spinner with Pine Research does a somewhat regular advance EIS webinar that covers circuit fitting in more detail. There a few UA-cam videos from us on the subject, like EIS of a perovskite film ua-cam.com/video/wixp3pKvKMc/v-deo.html and EIS of a PEM water electrolyzer ua-cam.com/video/db5xzuLJN4Q/v-deo.html. We've got a few more in the works, but follow us on twitter and check out our website for the next time we do an advanced EIS circuit fitting webinar.
Wow this was amazing, I'm so grateful for your explanation. This was so clear and concise. I have tried to understand through articles though they were very complicated, this however was so straight forward. Thank you so much!
To be honest, there is only really one tried-and-true method I know of that is used very frequently, and that is with respect to Pt. Very briefly, you use the knowledge that the Pt-H adsorption/desorption process has a theoretical specific capacity of 210 µC/cm2, and then you run a CV and take the area under the curve of i vs. time. You get units of C, then you divide by 210 µC/cm2 and you get a value of cm2. This is often considered the ECSA. There are likely other methods for other materials that are used, but the clearest and most common one is what I just described for Pt. I am not 100% certain what other methods researchers use, or perhaps they simply use geometric surface area and assume that is also equivalent to ECSA. I also understand this explanation is rather complex for a comment answer. What I will do is this upcoming Friday, August 9 2024 at 1pm EST, I will try to give a detailed demonstration of how this is done using real data and software calculations. This will be during our weekly "Ask Us Anything About Electrochemistry" livestream, it will be episode #62. Here is the link, whether you can watch live or you can see the recording on UA-cam afterwards: ua-cam.com/video/jNMp9a9J0lA/v-deo.html
Brief and simple, and the example of the orchestra finally made it clear for me as a total beginner! Thanks!
EIS is a very complicated subject, so we are really glad this video was helpful!
The best EIS intro video I saw till now. It really helped me to get an overview over EIS and its application. Much thanks and Greetings from Germany!
Glad it was helpful!
*Summary*
*Intro*
- *0:02**:* [Music]
- *0:10**:* Introduction to the video on Electrochemical Impedance Spectroscopy (EIS).
- *0:18**:* Acknowledgement of EIS's complexity and the video's introductory nature.
- *0:38**:* Overview of the video structure, covering EIS components, data generation, and application.
*What is Electrochemical Impedance Spectroscopy?*
- *1:29**:* Explanation of EIS as a technique using potentiostats to apply and measure sinusoidal potentials/currents in electrochemical systems.
- *1:50**:* Distinction between potentiostatic and galvanostatic EIS.
- *2:10**:* Characteristics of the sinusoidal potential applied and the corresponding output current.
- *2:57**:* Concept of phase shift or angle in EIS.
- *3:09**:* Procedure of conducting EIS experiments across multiple frequencies.
*Fourier Transform and what Impedance is*
- *3:36**:* Use of Fourier transform to convert time-domain data to frequency-domain.
- *4:00**:* Comparison of impedance calculation in EIS with Ohm's law in DC circuits.
- *4:39**:* Definition of impedance in the context of alternating currents or potentials.
- *5:00**:* Impedance as a measure of anything that impedes electron flow.
*The Bode Plot*
- *5:17**:* Introduction of the Bode plot from EIS data, showing impedance magnitude and phase angle.
*The Nyquist Plot*
- *5:48**:* Conversion of Bode plot data to Nyquist plot using cartesian coordinates.
- *6:03**:* Explanation of real and imaginary impedance in Nyquist plot.
*Analogy for understanding EIS*
- *7:09**:* Use of a symphony analogy to explain how EIS discerns different electrochemical phenomena at characteristic frequencies.
*Why use EIS?*
- *8:24**:* EIS's ability to probe different electrochemical phenomena at specific frequencies.
- *9:01**:* Contrast between EIS and other electrochemical techniques like DC voltammetry in analyzing concurrent processes.
*How EIS data is used (modeling an electrochemical system)*
- *10:09**:* Modeling complex electrochemical phenomena using circuit elements.
- *11:03**:* Combination of qualitative and quantitative analysis in EIS through circuit fitting and software.
*Conclusion*
- *12:01**:* Acknowledgment of EIS's complexity and a call for viewers to stay tuned for more in-depth content.
Thanks for the in-depth description
Clear, simple, and make absolute senses. I just want to say thank you to the dude who explaining this !!!Great job man !!!
You are very welcome! Happy you enjoyed the video :)
I have been doing EIS this week and wanted a clear explanation of EIS basics. This video helped me understand and interpret my data. Thank you very much! Great help!
We're really glad it was helpful!
Can you please suggest some open source eis data fitting software fit for biosensing application.
Thank you so much for this wonderful explanation. I've been trying to make sense of nyquist plots for some time now and none of the websites I visited made it this simple and clear.
We appreciate the comment, glad it was helpful for you! I think making sense of EIS data is a lifelong task, to be honest I'm not sure it ever completely makes sense! :D
One of the best educational videos I have ever seen on UA-cam!
Thank you so much! Stay tuned for more educational electrochemistry videos from us :)
Best overview of EIS I ever saw. Better than my university professor's
We are glad you liked it! I would also say that university professors can get caught up in the weeds of the technique, but we prefer a simpler and more accessible approach to the technique :)
@@Pineresearch Speaker is very well learned about the technique
@@dimple7267 Thank you! I did a lot of preparation for the video and consulted several colleagues to make sure the content was accurate :)
the best video on that topic so far. Thank you!
We are glad you liked the video! :)
Extremely eloquent and helpful video
Glad you liked it
It was 12 minutes of pleasure, simple clear and easy explanation of eis. Please keep entertaining us with electrochemical technics especially those applied for electrocatalysis and rechargeable batteries…
Thanks, will do!
You have no idea how your videos helped me with my studies! Thanks a lot!
Happy to hear that! Stay tuned for more!!
I am very grateful for your easy and simple explanation for such a important technique.
Glad you enjoyed it!!
Great piece of presentation
Glad you liked it!
WOW! The best video on EIS by a mile and a half!
Thank you! We are really glad you enjoyed the video and it was helpful!
Really impressive....Easy & simple explanation ...Salute to your effort..
Much appreciated!
Thanks for such an explanation in simple words with accurate analogies.
Thank you, glad you enjoyed it!
This is an amazing video for getting the first look at EIS. Thank you very much for sharing!!!! I love it.
Glad you enjoyed it!
the best explanation about EIS in yt fr
Thank you!!
Thank you for your explanation! As a beginner in this field, i really need this kind of videos to help me understand this field.
You're very welcome!
clear and crisp explanation, Thanks for video!
Glad you enjoyed it!
This is indeed one of the best videos simplifying EIS concepts.
Thank you Nikhil! I appreciate the comment. It was good seeing you at MRS :)
As a total beginner on the subject this was a great intro - well delivered and really enjoyable. That you :)
Thank you, we appreciate the comment and glad you enjoyed the video!
This is so complex but your explanation helps me a lot to understand it
EIS is probably one of the most complex areas of electrochemistry, and electrochemistry itself is pretty complex. We tried to make the introduction to the field as easy to understand as possible. But it will take some time and experimentation to really understand it. Thanks for watching!
I need video explaining how to use eis and which test I should select. I have like 8 option in my system. I'm confused and also how u determine if the same has high or low corrosion resistant from z real zcimag graph. I saw all your video but non explain what is the data mean in that I get.
Thank you so much
I'm glad you enjoyed the video. It's one thing to understand EIS conceptually, it's another to do it on a real system and understand what it means. We have a bunch of other videos on EIS that go into more details, for example, our video on EIS of coated steel corrosion ua-cam.com/video/Ov1KKDWLq0s/v-deo.html
Excellent, concise introductory video for beginners. :) Thanks
Glad you enjoyed it, thank you for the comment!
Perfect, clear explanation. Many thanks!
Glad it was helpful!
It was such a simple and excellent explanation in a 12-minute video. Many thanks.
Glad it was helpful!
Thank you for your wonderful presentation. Can you please suggest some open source eis data fitting software fit for biosensing application
Pine Research's AfterMath software is free to download (you just need to make a free account) and it has EIS circuit fitting. We also have some tutorials on circuit fitting on our UA-cam channel. pineresearch.com/shop/kb/knowledge-category/software/
Thank you so much. These topics are so crucial for electrochemical research but seldom explained to this level of clarity.Waiting for more such educational videos..
We are glad you enjoyed the video. Yes, we're looking forward to making more videos like this, so stay tuned!
@@Pineresearch could you please do videos on ionic conductivity,arrhenius plot and other important topics on solid electrolytes
@@sreyabnambiar150 I'll make the effort. There are a lot of electrochemistry topics we want to cover. So I'll add these to the list. Thank you!
@@Pineresearch Thank you soo much and wish you good luck for your future endeavours
@@sreyabnambiar150 Thank you! You too!
thank you, it was a nice presentation. I have a doubt why two phase change occur
I'm glad you enjoyed the presentation. What do you mean by "doubt two phase change occur"?
@@Pineresearch in the Nyquist plot, I am getting two semi circles. what does it mean?
@@ayushisinghal1379 Hello Ayushi. Two semi circles means that you have two Randles circuits (resistor and capacitor in parallel) in series. Physically, your electrochemical system has at least two interfaces. Does this make sense? We have free circuit simulation software you can download off our website
pineresearch.com/shop/kb/knowledge-category/downloads/
You just need to create an account, but then you can download AfterMath software and under the Analysis/Tools select circuit simulation. You can then see what the Nyquist plot with two Randles circuits in series look like and how the two semi-circles change. I hope this helps.
@@Pineresearch it is quite complicated but thank you
@@ayushisinghal1379 Another resource that might help is our knowledgebase article
pineresearch.com/shop/kb/theory/eis-theory/eis-basics/
Section 3 in particular goes into circuit fitting and the Randles (RC) circuit. The article only describes the simple case of one semi-circle however. If you have two RC circuits in series you would get two semi-circles, using the same logic described for the one semi-circle case.
I have questions please, what is the point of doing model for EIS ? Do the circuit represent the electrochemical reaction so basically we can use it as model for our system????
Your exactly right. EIS data by itself isn't very useful, it's only useful when you use it to model an electrochemical system, using the circuit elements as parts of your system.
Are phaseshift counted by, max time input amplitude - max time output ampitude ?
In reality there are some special transformations a potentiostat/software does to calculate the phase shift. However, you are correct, the phase shift can be thought of as the time delay between the input and output max amplitudes. But it's also the delay between every other point as well. The maximum amplitude is the easiest to visualize when it comes to visualizing the phaseshift. Remember, that both input and output signals must have the same frequency for it to be impedance. I hope this helps.
simple yet very clear explanation, thanks.
You're very welcome!!
great video! watched several videos before this and didnt understand until now :)
We're really glad that this helped. EIS is certainly a complicated subject, and we tried to make it as simple as possible.
Excellent presentation and content
Thank you!
This is fantastic! Looking into EDL and had no idea how EIS worked before this
Great, thanks so much for your comment and I'm glad it was helpful!
Thank u for providing such a knowledgeable and important video in free of cost. The way you explained everything, is really comprehensible. NeverthIess, I have one question regarding this EIS, I hope You will address my doubt.
I have seen a video in you tube where Mott Schottkey plot was done from EIS data. I have used the same method to plot Mott Schottkey from EIS, but in EIS data, no potential data column was given, which is required to plot Mott Schottkey, instead a frequency column was given. I want to know if you have any idea how EIS data can be used to plot Mott Schottkey.
Thank u
Thank you for your kind words. I'm no expert at Mott-Schottky, my colleague Dr. Neil Spinner prepared the advanced EIS webinar on the topic. But you are correct, Mott-Schottky requires a column of potential data as well to perform the analysis. What that means is you will need to perform EIS experiments centered around multiple potentials. So it's a fairly long experiment. Does that make sense?
clear explanation , Easy to understand thank you
You are welcome!
how it is measuring the corrosion and corrosion resistant
The impedance itself is the resistance, so if you are studying a corrosion inhibitor you should observe a large increase in the resistance when the inhibitor is added. But most people study corrosion using techniques like linear-polarization resistance (LPR) which gives you things like the corrosion rate.
Well made video! Took notes!
Glad it was helpful!
you deserve all my appreciation thanks
Hahaha, you are too kind. Thank you!
@@Pineresearch hhhh thank you for your comment, but I benefited a lot from your explanations
Perfect explanation for new beginners.. thank you..
We appreciate your comment and watching our video! If you have more questions you want to ask us, feel free to join one of our Livestreams on Fridays at 1pm EST, we try to answer electrochemistry questions every week.
Thank you for this lucid explanation!
You are very welcome!
Thank you. Crystal and clear explanation.
Glad it was helpful!!
Thank you for your explanation, I finally understood the basics.
But can I calculate the solution resistance without a programm? I can measure all important values but I don’t have an analysis programm.
Thank you!
I am not sure exactly what you mean by "without a program." If you have an instrument capable of performing EIS, then you should be able to calculate the solution resistance, yes, even if you do not have software that automatically displays the result for you. All you need to do is perform an EIS experiment over a few decades of high frequency (i.e., 100 kHz to 1 kHz will likely be sufficient), then obtain a reasonable estimate one of two ways: first, on the Nyquist plot you can find the point closest to the x-axis (where the y-axis -Zim value is smallest) and take that corresponding Zreal value to roughly be equivalent to the solution resistance. The second method would be to use the Bode plot and take the corresponding |Z| value where the phase angle is closest to zero. Either will likely give you a similar value and should be equivalent to the solution resistance.
You answered my question perfectly, thank you! Will the measurement change my solution or can I reuse it for other measurements like CV or EIS at a different temperature?
@@NadineLachmann One of the great things about EIS is that it is fundamentally non-invasive, so almost certainly the measurement itself should not impact your solution, no. That means you should be able to measure the solution resistance and then use it for subsequent experiments.
However, I should be clear that if you change the temperature, it may have an effect on the solution resistance. I suggest you measure and use the solution resistance value unique to each temperature you wish to conduct further experiments at, whether CV or EIS.
That‘s exactly what I want to do! I want to determine the solution resistance for three different temperatures to get a better understanding of my system! Thank you so much!😊
Thanks for such a great description of EIS
Glad you liked it!!
What if I want to learn deeper about EIS, do you have any recommendations for videos?
We have a bunch of advanced EIS videos from our webinars. I would also recommend checking out our free webinars we offer. We are actually offering a 5-part EIS webinar starting February 2nd. pineresearch.com/webinar-registration/ This would give you a deeper dive into EIS.
Amazing explanation... This will be very helpful for my research project..
Glad it was helpful!
Great introductory video
Thank you!
I can just say , you and your explanations are perfect!
Thank you so much! Glad you liked it!
harika bir video. bir hadise ancak bu kadar güzel anlatılabilirdi. congratulation ❤
Needed to use google translate for this. Thank you, I'm glad you enjoyed it
Excellent Video! simple brief but useful. make more videos plz
Thank you so much for the kind words, I'm glad you enjoyed the video!
What is analyte, cation and anion and solvent he refers to?
Analyte, cation, anion, and solvent are the chemicals used in an electrochemistry experiment. The solvent is usually the liquid like water, acetonitrile, dimethyl sulfoxide, etc. The cation and anion make up the salt that is added to the solvent. So a salt like NaCl, would dissolve in the solvent forming Na+ and Cl-. Na+ is the cation and Cl- is the anion. The analyte is the generic term for the molecule you are studying. I hope this makes sense.
@@Pineresearch Thank you so much for your clarification. God bless.
Thank you so much for the great explanation
You are welcome! Glad it was helpful!
Hello sir, we perform EIS experiments on our own potentiostate (CH instrument). Is your webinar going to be helpful for our EIS data analysis or is that solely for pine research instruments ?
Out 5-part EIS webinar series is general for EIS and can be useful for anybody trying to learn EIS regardless of the potentiostat they use. For parts of the webinar that go over circuit fitting, we will be using Pine Research's AfterMath software to perform the circuit fitting. But you can use other software to perform circuit fitting. I hope this was helpful.
@@Pineresearch thank you so much
This video was really helpful for a good understanding about EIS. Thank you.
You're very welcome!
Thank you so much for such a video full of knowledge and explain in such a simple way. I hope to see more videos in this regard specially on EIS of ceramic electrolyte and how EIS help us to find bulk resistance, grains and grain boundaries resistance, charge transfer resistance and warber. and also stay connected with you guys.
Absolutely! Glad you enjoyed the video!
Amazing video, great analogies. Just hands-on knowledge!
Thank you kindly!
That is perfect for a beginner. Thank you!
Glad you enjoyed it!
really congrats from the bottom of my heart
Thank you very much!
You just saved my life!! Thank you 🥺
I'm so glad it the video was helpful. I never considered electrochemist as a life saving career :)
Thank you for such amazing explanation of EIS
You're very welcome, glad you enjoyed it!
Thank you for your good explanation. Recently I was figuring out how to use EIS to calculate the diffusion coefficient. In many literatures the researchers just simply carried out a EIS test and then used the equation D=(R^2*T^2)/(2A^2*n^4*F^4*C^2*σ^2). I feel confused about what is semi-infinite diffusion, the physical meaning of warburg coefficient, in what circumstances can I use the equation. What is the differences between soluble analyte (analyte diffusion) and solid analyte (counter ion diffusion)? Maybe too many questions haha.
I completely understand. These are great questions, and might be a bit too much to address in a single UA-cam comment. Shameless plug aside, Pine Research is offering a free EIS webinar series pineresearch.com/eis-webinar-series-registration/ it's run by my colleague Dr. Neil Spinner, and I think you'd get a lot out of it. To address questions about warburg coefficients, semi-infinite diffusion, etc he will probably talk about those in the later parts of the series (part 3, 4, and 5). However, I would encourage you to attend the whole thing. I hope this was helpful.
Thank you so much for breaking down such a complex technique!! I definitely owe you so much, man.
glad you enjoyed the video! Always happy to help!
excellent explanation!
Thank you!! Glad you enjoyed it
Excellent explanation! Thank you!
Of course! I'm glad you liked it!
Which software are you using for fitting the EIS circuit.
We use AfterMath Blue, which is Pine Research's software. AfterMath Blue is free, but to do circuit fitting it will require a paid license. Let me know if you are interested.
I want to know the separarion of double layer capacitance and pseudocapacitance by analysing the nyquist plot..the value of specific capacitance..plz suggest.
To be honest, I'm not sure there is an effective way to perfectly distinguish using EIS data between Cdl and pseudocapacitance. My best guess would be that perhaps you can fit with a constant phase element (CPE) and monitor the value of α you get. Perhaps a value that indicates severe non-ideality (something like 0.6-0.8, for example) could be a marker for non-ideal capacitance or pseudocapacitance. But this is more of an educated guess as to how you might make that distinction, since as I noted I am not 100% certain EIS data can easily help you analyze and differentiate between those two phenomena.
@@Pineresearch I appreciate that you took the time to respond to my comment.
@@surajittalukdar5536 It is my pleasure. You can comment any time, we check our UA-cam comments every day and always make efforts to reply. You can also join us on Fridays at 1pm EST for our weekly Livestreams if you like and want to ask any questions that we can answer for you live. It is a little more interactive than the comments section I think :)
Super well explained
Thank you Gaspar! EIS is complicated and we wanted to make it as simple as possible.
This is really useful for me, nice explanation..
Glad it was helpful!
Its a very good explanation but can you please elaborate about why in Nyquist Plot the value Zimaginary is in negative scale??
Plotting negative Zimaginary is mostly a convenience thing. For most systems the imaginary impedance is negative, so we would be able to plot data in the 1st quadrant rather than the 3rd in a graph. But fundamentally, negative imaginary impedance comes from capacitive processes, the impedance of a capacitor is -j/wC. So the negative sign is just part of the equation.
how to calculate total resistance from EIS niquis plot....???
The beauty of EIS is that there isn't necessarily a total resistance, but a resistance measured across different frequencies. The total resistance by itself isn't as useful. I suppose my question to you is, what is your system and what does the total resistance mean?
Also, if you have most specific questions you can reach us at pinewire@pineresearch.com, we don't have a specific WhatsApp account.
we hav prepared cds@GO nanocomposites s n anode material for energy storage batteries & we want test electrochemical performance & totl resistance..
sir plzz check your email
@@lovelykhattak9121 We haven't received an email. What email address is it coming from? It might have gotten stuck in our spam filter.
what does different "time" and different "time scale" exactly mean?
Time scale (at least in this context) refers to something that oscillates, so we are talking about the frequency of a repeating motion. Imagine two separate wheels that are spinning. One is spinning at 1 mph, the other is spinning at 100 mph. The frequency or time scale of the two wheels are very different. If I marked both wheels with yellow paint I could easily watch the yellow mark on the wheel spinning 1 mph. But it would appear as a blur if I watched the 100 mph wheel. Both wheels are spinning at the same time, but I can only detect the motion of the 1 mph wheel. Does this help?
@@Pineresearch wonderful and clear description :) thank you so much ! i was always so confused with that concept
Hello, Good morning, I appreciate the knowledge shared on this channel. Studying about the EIS technique I have a doubt that I have not yet been able to solve clearly, the question is What does it mean that a material has its phase angle at lower or higher frequencies than another material? In which of these cases would there be a higher resistance to corrosion?
Hello Jose, thanks for your question. First of all, I want to clarify that when you write "...material has its phase angle..." I assume you are referring to a kind of graphical dip in the phase angle on the Bode plot that is observed for features that are often fitted with a Randles circuit. If this is the case, then the simplest answer I can give you (neglecting all other processes that might be occurring on your materials of interest) is that the phase angle peak is related to the capacitance and the time constant.
To elaborate just a little bit: if the capacitive effects being observed are very small, it means it can be charged/discharged very rapidly, meaning the peak will manifest at higher frequencies. Conversely, if the capacitive effects are very large, it will take longer, or be slower, for the charge/discharge phenomena to occur, meaning the phase peak will appear at lower frequencies.
All of the above is also neglecting the resistance, which can also have an effect on where the phase angle peak appears; and on the time constant, which is a pseudo-measurement of how long this charge/discharge process takes.
Finally, to address your question about corrosion resistance: the position of the peak *may* give insight into the corrosion resistance, but not necessarily. For example, following the previous discussion on capacitance: if the phase angle peak is at high frequency, it likely implies lower capacitance and a somewhat smaller time constant, which could also imply a smaller resistance. But it is not guaranteed that is the case. You can have a large resistance even with a small time constant if the capacitance is just extremely small. Conversely, a phase angle peak at low frequency might imply higher capacitance and a larger time constant, which could imply a larger resistance; but again, this is not guaranteed because you could still have a small resistance even with a large time constant. This is because the time constant is equal to R times C, so a proper circuit fitting analysis would likely be required to reveal whether your material is exhibiting high or low corrosion resistance.
i got impedance vs current datas from an elctrochemocal mesurement. I do look for a software (OA) to modell these ... any requests?
I need a little more clarification on the data and modeling you are interested in. Usually, impedance is not plotted or measured with respect to current. You typically get Nyquist and/or Bode plots which plot the real impedance vs negative imaginary impedance (Nyquist), or the impedance magnitude and phase vs the frequency (Bode). I suppose the question is, what exactly to you want to do?
@@Pineresearch sorry, I was wrong these are typical data z' vs. z''. I got just an excel with the datas and dont have access to silulation software. Need help.
@@WolfdietrichMeyer You can use our AfterMath software to do circuit fitting. It can't be downloaded for free off our website. You only need to create an account (also free) on the website, to download it. pineresearch.com/shop/kb/knowledge-category/downloads/ Once you have AfterMath on your computer under File--> Import External Data you can import a CVS file of your EIS data. Let me know if you need additional clarification. I hope this helps.
great explanation,,, thanks
Glad it was helpful!
Lovely explanation. Thank you so much. Kindly release more videos like this about Cyclic voltammetry and GCD
Glad you enjoyed the video. I definitely plan on making more videos about these different electrochemistry topics :) . Stay tuned!
You made that really easy to understand, cheers. I can't wait to get stuck in to some serious characterisation :)
I'm happy to hear that. We've got some Advanced EIS Webinars and circuit fitting UA-cam videos that might be helpful for whatever system you are looking to characterize.
Thank you for the explanation. It is very helpful.
Glad you found it useful, thanks for the comment!
Can you give an idea about K-K Analysis for validation of EIS data, how we can implement it in real EIS data.
I can only speak on behalf of Pine Research, but our AfterMath software performs K-K analysis to validate your EIS data. If you are using another potentiostat you can important your data to AfterMath, and there is an option to perform K-K. Then you can look at how well the fit is and the chi-squared value to see if you EIS data is valid. You can download AfterMath for free and use our circuit fitting and K-K analysis tools. All you need to do is create a free account on our website.
pineresearch.com/shop/knowledge-category/downloads/
Thank you so much. Please help me with another query. What is the acceptable chi-squared value for EIS data in KK analysis. I have EIS data that gives 0.0008 chisq value. Is the data valid?
@@yeasmins074 The problem with judging a fit by chi squared is that there is not an easy universal metric to gauge whether it is good or bad. Whether you are doing circuit fit or K-K analysis, chi squared should generally be used as a comparison across multiple analyses on the same data. For K-K in particular, it is both quantitative through chi squared but also extremely subjective. You may have to determine for yourself how closely the fit appears to match your data and make a determination from there. You may also find, for instance, some frequencies fit better than others. Sometimes the low frequency points don't match as well because of drift, but the mid to high frequency points do, so you can propose most of your data are valid but the lower frequencies are less accurate. But overall, it is not simple to give a set universal chi squared metric for saying definitively something like "larger = bad, smaller = good"
Thank you for the response ❤.
Great explanation. Thank you for your sharing.
Thank you for the comment, and we appreciate you watching our content!
Thank you! this video helps me to know EIS
Glad you enjoyed it!
Thanks for the great explanation. However, how the schematics structure looks like for the EIS measurement system?
Are you referring to how does the potentiostat operate in order to perform EIS? I just want to clarify the question.
@@Pineresearch Yes, and at the same time I am talking about: how the electrical components e.g., resistor, capacitor and inductor can be shown by the diagram in schematic. You have shown & explained the circuit diagram at the end but I would like to know the whole process including all components in one diagram.
@@tanzilanurjahan6609 Well first, I would recommend watching our "How a potentiostat works" video ua-cam.com/video/pzB122dTij8/v-deo.html
But regarding the circuit elements of how a potentiostat works with regard to EIS I cannot provide you with a circuit diagram. First, there are proprietary reasons and second, it's too complex for one diagram. But the key takeaway with regard to how a potentiostat works from an EIS perspective, is that the potentiostat requires what is called an FRA (Frequency response analyzer). This allows your potentiostat to take in AC signals (necessary for EIS). Are you trying to build an EIS capable potentiostat from scratch?
@@Pineresearch . I am trying to understand the whole circuit diagram of EIS runs on. You are right it's complex. However, Thanks for your assistance.
@@tanzilanurjahan6609 You're welcome. I think the best way to understand the circuit is to check out the video I mentioned before about how a potentiostat works. This will help you understand how a potentiostat maintains a set potential and measures the current response. You can then think of the potentiostatic setpoint (from the circuit in that video) as the waveform generator for producing a sine wave. And subsequently, you can think of the E/I voltmeter which allows us to indirectly measure the current, as a way to measure the sinusoidal current response. Then you do all the calculations performed in this video.
Great video. Keep them coming bro!
Thank you! Yes, I've got another one in the works. Stay tuned :)
Thanks! really well explained
We are glad it was helpful!
Thanks for this easly explanation about EIS❤
Thank you liked it!
Really great video !
So glad you liked it!
Excellent video, thanks a lot!
You are welcome! We've glad you liked it!
Thanks for the video! Would really appreciate another one going deep into circuit fitting.
Thank you Luiz! Actually, Dr. Neil Spinner with Pine Research does a somewhat regular advance EIS webinar that covers circuit fitting in more detail. There a few UA-cam videos from us on the subject, like EIS of a perovskite film ua-cam.com/video/wixp3pKvKMc/v-deo.html and EIS of a PEM water electrolyzer ua-cam.com/video/db5xzuLJN4Q/v-deo.html. We've got a few more in the works, but follow us on twitter and check out our website for the next time we do an advanced EIS circuit fitting webinar.
@@Pineresearch Thanks a lot! I'll definitely look into those!
thank you it's helpful in my post graduation project 🙏
We are happy it's helping you for your post graduation project. EIS is challenging to learn.
Amazing video, understood everything!
Glad it helped!
Great explanation! I loved the analogy to an orchestra! Looking forward to more videos on this topic :D
Glad you liked it!
Wonderful. Thank you!
Glad you enjoyed it!
Wow this was amazing, I'm so grateful for your explanation. This was so clear and concise. I have tried to understand through articles though they were very complicated, this however was so straight forward. Thank you so much!
Yeah, there are a lot of complicated articles and books on EIS. I'm glad the video was helpful!
You are a great teacher! 👌🙂
Thank you! 😃
This was very helpful, thank you!
We are glad that you liked the video!
this is so helpful thank you!!
You're so welcome!
Appreciate the details and specificity 💯🙌🏼
Happy to help!
how to calculate electroactive surface area?
To be honest, there is only really one tried-and-true method I know of that is used very frequently, and that is with respect to Pt. Very briefly, you use the knowledge that the Pt-H adsorption/desorption process has a theoretical specific capacity of 210 µC/cm2, and then you run a CV and take the area under the curve of i vs. time. You get units of C, then you divide by 210 µC/cm2 and you get a value of cm2. This is often considered the ECSA.
There are likely other methods for other materials that are used, but the clearest and most common one is what I just described for Pt. I am not 100% certain what other methods researchers use, or perhaps they simply use geometric surface area and assume that is also equivalent to ECSA.
I also understand this explanation is rather complex for a comment answer. What I will do is this upcoming Friday, August 9 2024 at 1pm EST, I will try to give a detailed demonstration of how this is done using real data and software calculations. This will be during our weekly "Ask Us Anything About Electrochemistry" livestream, it will be episode #62. Here is the link, whether you can watch live or you can see the recording on UA-cam afterwards: ua-cam.com/video/jNMp9a9J0lA/v-deo.html