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
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!
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…
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 :)
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 so much. These topics are so crucial for electrochemical research but seldom explained to this level of clarity.Waiting for more such educational videos..
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!
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.
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.
May you live long gentleman! How simply and concisely you described it. Keep it up! 😊 100/100 for you! If I could go more than 100 then I would have gone further
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.
We are very glad that you enjoyed the video and thought it was helpful. We are based in the US, so we are glad we provide some transcontinental help :)
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?
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
Hello Leila, we are glad you enjoyed the video. Describing warburg and pseudo-capacitive behavior is probably a topic for another lengthy video. But in short, a warburg element is used for the impedance associated with diffusion, which one can observe with the 45 degree tail on the Nyquist plot in the low frequency region. Constant phase elements (CPE's) are circuit elements used to describe pseudo-capacitive behavior. A capacitor is two charged parallel plates separated by a dielectric. Sometimes in electrochemical systems you'll get things that are almost like a capacitor, but not entirely...because it's electrochemistry :D . So it's hard to circuit fit an electrochemical system to an ideal capacitor because almost nothing in electrochemistry is ideal, so we use a CPE instead. I hope this was helpful. Stay tuned for more!
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.
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.
*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.
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/
@@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.
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.
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.
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.
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.
@@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.
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!
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
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!
I am very grateful for your easy and simple explanation for such a important technique.
Glad you enjoyed it!!
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!
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 :)
Thanks for such an explanation in simple words with accurate analogies.
Thank you, glad you enjoyed it!
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!
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
You have no idea how your videos helped me with my studies! Thanks a lot!
Happy to hear that! Stay tuned for more!!
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!
simple yet very clear explanation, thanks.
You're very welcome!!
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!
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 :)
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 :)
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, 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!
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.
clear and crisp explanation, Thanks for video!
Glad you enjoyed it!
Thank you. Crystal and clear explanation.
Glad it was helpful!!
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.
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!
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!
clear explanation , Easy to understand thank you
You are welcome!
That is perfect for a beginner. Thank you!
Glad you enjoyed it!
Excellent, concise introductory video for beginners. :) Thanks
Glad you enjoyed it, thank you for the comment!
the best explanation about EIS in yt fr
Thank you!!
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 :)
Really impressive....Easy & simple explanation ...Salute to your effort..
Much appreciated!
Thank you for this lucid explanation!
You are very welcome!
This video was really helpful for a good understanding about EIS. Thank you.
You're very welcome!
I can just say , you and your explanations are perfect!
Thank you so much! Glad you liked it!
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 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!
Great piece of presentation
Glad you liked it!
Thank you so much for the great explanation
You are welcome! 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!
Amazing explanation... This will be very helpful for my research project..
Glad it was helpful!
Thank you for such amazing explanation of EIS
You're very welcome, glad you enjoyed it!
Thanks for this easly explanation about EIS❤
Thank you liked 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!
really congrats from the bottom of my heart
Thank you very much!
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!
Thanks for such a great description of EIS
Glad you liked it!!
Thank you! this video helps me to know EIS
Glad you enjoyed it!
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!
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.
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 Video! simple brief but useful. make more videos plz
Thank you so much for the kind words, I'm glad you enjoyed the video!
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 explanation! Thank you!
Of course! I'm glad you liked it!
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.
May you live long gentleman! How simply and concisely you described it. Keep it up! 😊 100/100 for you! If I could go more than 100 then I would have gone further
Awwwww thank you so much for the very kind words :)
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!
This is really useful for me, nice explanation..
Glad it was helpful!
awesome , informative and impressive explanation!Thanks for sharing--(I''m a che student from asia)
We are very glad that you enjoyed the video and thought it was helpful. We are based in the US, so we are glad we provide some transcontinental help :)
Well made video! Took notes!
Glad it was helpful!
Wonderful. Thank you!
Glad you enjoyed it!
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?
Excellent presentation and content
Thank you!
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
You are a great teacher! 👌🙂
Thank you! 😃
Super well explained
Thank you Gaspar! EIS is complicated and we wanted to make it as simple as possible.
excellent explanation!
Thank you!! Glad you enjoyed it
Beautifully explained 🙏🏻❤️
Glad you enjoyed it! :)
Great explanation. Thank you for your sharing.
Thank you for the comment, and we appreciate you watching our content!
thank you so much for such great job , please continue it, if you can please explain about warburg and the pseudo-capacitive behaviour in circuit.
Hello Leila, we are glad you enjoyed the video. Describing warburg and pseudo-capacitive behavior is probably a topic for another lengthy video. But in short, a warburg element is used for the impedance associated with diffusion, which one can observe with the 45 degree tail on the Nyquist plot in the low frequency region. Constant phase elements (CPE's) are circuit elements used to describe pseudo-capacitive behavior. A capacitor is two charged parallel plates separated by a dielectric. Sometimes in electrochemical systems you'll get things that are almost like a capacitor, but not entirely...because it's electrochemistry :D . So it's hard to circuit fit an electrochemical system to an ideal capacitor because almost nothing in electrochemistry is ideal, so we use a CPE instead. I hope this was helpful. Stay tuned for more!
great explanation,,, thanks
Glad it was helpful!
Excellent video, thanks a lot!
You are welcome! We've glad you liked it!
Appreciate the details and specificity 💯🙌🏼
Happy to help!
Great explanation! I loved the analogy to an orchestra! Looking forward to more videos on this topic :D
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.
This was very helpful, thank you!
We are glad that you liked the video!
Thanks! really well explained
We are glad it was helpful!
Great introductory video
Thank you!
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.
Amazing video, understood everything!
Glad it helped!
*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
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/
this is so helpful thank you!!
You're so welcome!
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.
It's very helpful thank you so much
Most welcome 😊
Great video, thanks
Glad you liked it!
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.
Life saver, Thanks!
Awesome! I'm glad the video 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.
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
Really great video !
So glad you liked it!
great video! thanks a lot!
We're glad you enjoyed it!
Very helpful!!!
Thank you!!
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.
Great video. Keep them coming bro!
Thank you! Yes, I've got another one in the works. Stay tuned :)
thank you sir :) that's wonderful explanation :)
We're glad you liked 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 class.
Glad you enjoyed it!!