🌟 Graphene Nanotunnels: Welcome Onboard with Ashok Keerthi: Episode 198 of Under the Microscope 🔬

What to Expect:

In this episode, Ashok Keerthi delves into his innovative research on graphene nanotunnels. Ashok shares his journey from studying chemistry in India to working at the University of Manchester. He discusses his work on creating atomic-scale capillaries within graphene layers and their potential applications in molecular transport and filtration.

About the Guest:

🌟 Key Takeaways from This Episode:

• Graphene Nanotunnels: Creating atomic-scale capillaries in graphene for molecular transport.
• Career Journey: From studying chemistry in India to conducting groundbreaking research in Manchester.
• Favorite Experiment: Investigating helium transport through graphene capillaries.

🔬 In This Episode, We Cover:

Ashok’s Research:

Ashok’s research focuses on creating atomic-scale capillaries within graphene layers. By removing specific layers of graphene, he creates tunnels only a few angstroms thick, which can be used to study molecular transport and filtration. His work aims to harness the unique properties of graphene for various technological applications.

Ashok’s Career Journey :

Ashok’s academic journey began with a Bachelor’s in Chemistry in India. He pursued his passion for nanoscience, leading him to conduct research in Singapore, Germany, and now Manchester. His diverse experiences have enriched his research perspectives and expertise.

Ashok’s Favourite Research Experiment:

Ashok’s favorite experiment involves investigating the transport of helium through graphene capillaries. By studying how helium moves through these atomic-scale tunnels, he aims to understand their potential for filtration and molecular transport applications.

Life as a Scientist- Beyond the Lab:

Ashok values the collaborative nature of scientific research and enjoys engaging with the global scientific community. He is passionate about teaching and mentoring the next generation of scientists and values the opportunity to work in a cutting-edge field.

Ashok’s 3 Wishes

1. Increased funding for research: Ashok wishes for more financial support to advance innovative research projects.
2. Greater collaboration between researchers: He advocates for stronger partnerships to enhance knowledge sharing and collaborative efforts in research.
3. Improved public understanding of scientific research: Ashok emphasizes the importance of public awareness and support for scientific advancements.

Ashok’s Time on @RealSci_Nano:

Ashok will be taking over the RealSci_Nano Twitter account to share his research on graphene nanotunnels. Followers can expect to learn about the innovative techniques and materials his work focuses on, as well as insights into the future of nanoscience.

Transcript

Speaker: [00:00:00] Hi, just finished recording a podcast with Ashok Kirti, who is a researcher at the University of Manchester, and he’s researching on graphene and the beautiful tunnels or capillaries that are made in these tunnels. one or two or three layers of graphene, which is the carbon atoms, uh, arranged in a honeycomb lattice and how, uh, how these are created and about Ashok’s journey in, in science, the research journey.

Speaker: And, uh, yeah, we talked about a lot of interesting things, so can’t wait for you to watch the video. Do consider subscribing and liking the content that we create on YouTube, on Spotify, on Apple podcasts, wherever you’re listening. Do share it with your friends. Uh, your support means everything to us. Uh, we are a very small channel, uh, run by volunteers.

Speaker: So please, please, please, uh, do share and, uh, interact and watch the entire video. Thank you very much.

Speaker: [00:01:00] Hi everyone. I am Pranavati, your host of Under the Microscope podcast. And today we have an amazing guest with us. And I’m totally not biased when I say this because he is also working on Graphene. Uh, so yeah, we have Ashok Kirti, who is a Presidential Fellow at the University of Manchester in England. By the way, Manchester is also the Birthplace of ene, um, and all of that.

Speaker: So yeah. Welcome Ashok. Uh, welcome to the podcast. Um, 

Speaker 2: thank you ate. Thank you very much. 

Speaker: Uh, before I get started with the, with the science itself, I do have a question for you. What is a presidential fellow? What, what, like do you get, like, do you shake hands with the president on a regular basis or what does it mean?

Speaker 2: Right. That’s very interesting. Um, so the presidential in, in the uk, uh, we have two streams for the assistant professor, uh, uh, level. So one is more mostly a [00:02:00] research based, uh, assistant professorships. The other is research based, uh, teaching. So the presidential fellow is a kind of research fellow route.

Speaker 2: Mm-Hmm. , which is equal into assistant professor in broader context. 

Speaker 3: Mm-Hmm. . But, 

Speaker 2: uh, mostly focusing on the research side. With a minimal amount of teaching. So, yeah. 

Speaker: Aha. So you can completely focus on the research and you do not have to, uh, think too much about the teaching part. 

Speaker 2: Digital of the time goes to the research and we, we do still, uh, participate in teaching.

Speaker: Okay. Okay. Excellent. Excellent. Uh, that sounds actually very cool. So, okay. Ashok, please explain your research to us in super simple words, please. I mean, we were talking earlier and I think your research is super fascinating. So tell our followers what your research is all about, what you’re doing right now.

Speaker 2: Right. So I think let’s, let’s, let me start with, uh, the famous example, what Manchester is known for. Yeah. So, you know, the graphite, uh, how the Manchester gave back to the graphene. Just peeling one layer of the graphene from the graphite crystal. Right. And [00:03:00] that’s how the graphene is invented. And, and Nobel Prize is presented.

Speaker 2: Mm-Hmm. . And so that’s all the story, which is now progressing the 2D materials research. But now, uh, in Manchester, what we were doing, um, instead of removing from the, you know, on the 2D crystal, 

Speaker 3: and 

Speaker 2: removing one layer of 2D material, so if we are removing something from the middle of the crystal and making such kind of tunnels, these are atomic scale tunnels.

Speaker 2: So, for example, if I remove one layer of the graphene from the graphite crystal, so just making a tunnel, which is only one atom. So one atom, one layer is missing that is 3. 4 angstroms, the thickness of the graphene. 

Speaker 3: So we’re 

Speaker 2: essentially making such kind of capillaries in the 2D 

Speaker 3: materials. 

Speaker 2: And we wanted to study the molecular transport of filtrations using such atomic scale capillaries.

Speaker: Oh my God, that is so cool. So you’re basically Digging nano tunnels. Um, in the, in like a graphite stack, you do nano or is there like a number of layers that you have, like a particular number of graphene layers, or is it like, do you take a stack of graphite? [00:04:00] 

Speaker 2: Right. Um, yes. That’s, um, a trick which is again, um, well known in 2D materials research.

Speaker 2: Now, when may people make, um, different 2D materials stacking them together? So the fa the, the, the term which is used is hetero structures, land, wall, hetero structures is the, uh, is the term in 2D materials. Mm-hmm. Right. So we’re using a similar technique, right? But stacking three crystals, uh, together, uh, in the middle crystal, we are making such kind of, uh, a ribbon of a 2D material and then keeping those ribbons as a middle layer spacer layer between the top and bottom.

Speaker 2: Crystal. 

Speaker 3: Uh huh. 

Speaker 2: Putting them together to end up with such kind of 2D tunnels. Ah! So it’s the end of the world machine. Yeah, this is exactly looks like you removing one layer from the middle of the crystal and making such capillaries. 

Speaker: Oh my God. So you start with the first, let’s say, I don’t know if this is a very bad example.

Speaker: Probably you take a slice of bread, which is the bottom layer. Then you have, let’s say like a tomato slice or whatever. And then on top, you have the bread and then you remove the tomato. Uh, but the two, Oh my God, this is so cool. I thought, Oh my God, I was wondering how you see [00:05:00] it. 

Speaker 2: That’s, that’s exactly what we’re doing.

Speaker 2: So for example, this is a 2D crystal. You peel it off and then make a slice, which is as a bottom layer. 

Speaker 3: And 

Speaker 2: then just take one layer of graphene or other 2D material and pattern that into ribbons. 

Speaker 3: And then 

Speaker 2: you place on top of the, uh, the bottom layer. Then you put another top layer so that you have two spaces sitting, and you create such kind of funnels.

Speaker 2: And then you close with another one. 

Speaker: Oh my God, and what is the gap is that like? Have you played with the gap? Like the or less the height of the tunnel? Uh, 

Speaker 2: yes. So yes, because now you’re placing this mechanically together, 

Speaker 3: right? 

Speaker 2: In a very simple manner. So you have a control on. How many spacer layers you want to keep in?

Speaker 2: You take a monolayer graphene, which is essentially 

Speaker: a 

Speaker 2: 3. 4 angstroms in thickness. 

Speaker: Wait, 3. 4 angstroms, that would be 0. 34 [00:06:00] nanometers, correct? 

Speaker 2: Yes, exactly. That’s right. So it’s, 

Speaker: Oh my God. Okay. 

Speaker 2: One nanometer. Now we are in a lower than nanometer 

Speaker: regime. Right. 

Speaker 2: So if you multiply those layers in the middle, like let’s say you take, Oh, Two layers of graphene 

Speaker: spacer, 

Speaker 2: and that is 6.

Speaker 2: 8 angstroms. 

Speaker: Correct. More than half, uh, this is very thick, I must say, um. 

Speaker 2: So yeah, we can control with the multiples of 3. 4 angstroms or 0. 34 angstroms to a number of spaces that you want. So you can precisely have a nanostructure. A nano tunnel at nano capillary 

Speaker: That is so cool. So based on the application if there is like a Uh, like a like someone walking then the height is different if there is a car the height is higher like bigger Or higher.

Speaker: And if there is a truck, then you have a high. Oh, my God. That’s sorry. I’m just going with like sandwiches and tunnels and 

Speaker 2: that’s very relevant. That’s exactly what we’re doing. So it’s like now you’re controlling such traffic, molecular traffic, 

Speaker: right? 

Speaker 2: By [00:07:00] increasing the barrier height. If you only want the, uh, the cycles, uh, you know, the pedestrians, then you lower it down and then say only these allowed 

Speaker: at the molecular 

Speaker 2: scale.

Speaker 2: That is so 

Speaker: cool. And everyone who’s listening to the podcast only, please, please check out the video on Spotify or on YouTube where Ashok showed his models and it’s so cool. You will get it instantly if you haven’t had a chance to if you can’t visualize the nano channels so far Please watch the YouTube channel the YouTube video on the science talk YouTube channel.

Speaker: And yeah. Oh my god. This is so fascinating Okay, Ashok now. I want to know more. So how did you end up? Being the nano, uh, tunnel creator and moderator or however I call it, how did you end up basically as a presidential fellow at the University of Manchester? How did that happen? Tell me about your journey, please.

Speaker 2: Wow. Um, yes. So it’s a bit unconventional way I end up here. Um, so basically I’m a chemist. I trained by, uh, trained as a chemist. I studied till my master’s in India, and then I did my PhD in synthetic organic chemistry, uh, in Singapore, National, National, uh, University of Singapore. Um, so then I did my postdoc, first of all, doctoral research in Germany, Max Planck Institute for Polymer Research.

Speaker 2: So again, I was working on polymers and [00:08:00] macromolecules, again, um, also on the graphene nanostructures. So the, those are like, um, a fragments of graphene, you take a graphene sheet and cut it into a small fragments. So we used to make such nano graphenes from the bottom up approach, like, let’s say, take one ring that is, uh, you know, equivalent to one benzene ring, few rings together, you fuse the rings as you want, and then you make a nanostructure precisely.

Speaker 2: So that’s what my background is. By when I came to Manchester, so I was, completely into a different side of the graphene taking a graphene graphite bulk crystals and to create such kind of um angstrom capillaries with the very talented So, scientists here. 

Speaker: Oh, wow. Okay. So you are the definite, you’re the poster boy of a traveling scientist starting your journey in India, then Singapore, then Germany.

Speaker: Um, and now in England. Wow. You have so much experience. I’m so impressed. Uh, that is wow. That is really cool. That is. Very, very cool. So it sounds to me a joke that you have been involved in a [00:09:00] lot of interesting research projects. I mean, 

Speaker 2: yes, lucky. I’m very lucky to say that. Yeah, yeah. 

Speaker: Yeah, I can, I can imagine.

Speaker: So this is a very difficult question, you know, I know before asking, so I’m just giving you a heads up. If you have to pick one research project that you’re most proud of, uh, and most fun or quirky one, could you pick one research project and explain it to us in simple words in the section we call In Other Words.

Speaker 2: Wow. Um, I, this is really a difficult question because see, uh, my journey, it’s, it’s, it’s a multidisciplinary and started from a chemist to into the physics and interplay in interdisciplinary. So I think, um, difficult for me to choose one, but, um, yeah, for the sake of choosing one, I will choose one, um, is really interesting to me apart from the other projects.

Speaker 2: So when we created such, uh, 2D tunnels. So we wanted to know if these tunnels are open or not, because we are just removing one layer from the middle of the, I mean, one layer thick to the tunnels, we are not very sure if they are fully [00:10:00] clean or is anything stuck here, you know, we can’t go see. These are not like pipes where you can easily inspect.

Speaker 2: Yeah. So you need to know if they are very clean or inside there is nothing stuck. So we wanted to study, uh, the gas transport. We just wanted to put some gas molecule from here and then measure from the other side and we wanted to know if they, these are open or not. That was an intention. So when you put a gas molecule such as a helium, which is chemically inert, 

Speaker: Well, helium is the one which, if you, if you inhale it and then you sound funny.

Speaker: That’s like the, it goes like the high pitch. That’s the helium. Right? 

Speaker 2: That’s, that’s what, yes. Yes. Exactly. You did the same here. It made some funny observation. I would say scientifically very interesting one, but to say it’s funny. So it went through it, but how much we, you know, we know the dimension of this capillary because we made it now.

Speaker 2: We know exactly how much size is it. And we can compute back using a known theorems. And we know some X amount has to come, but it has come 100 times the X. Right. 

Speaker 3: Correct. 

Speaker 2: That was again, uh, very intriguing why this [00:11:00] is coming so much, but we expect a hundred times more. Yeah. So more than 

Speaker: that. So, sorry. So you, uh, according to your calculations, you put an X amount of helium and you expected X amount to come back, come, come out.

Speaker: But actually what came out was a hundred X. 

Speaker 2: Um, you know, that’s, uh, I think may let me again, simplify, sorry for that. That’s okay. Okay. Yeah. So it is not the X amount is a speed, a flux, a flux rate, 

Speaker 3: right? 

Speaker 2: Supposed to come this much, me, you know, me to, uh, it’s the velocity with which it should come out. I mean, very fast.

Speaker 2: We come in a, in a certain time, that whole amount, but it is coming very fast. Like let’s say you’re throwing a ball to a, a pipe. 

Speaker 3: Yeah. 

Speaker 2: You expect to come with a certain velocity of flux at some point, but as you throw here, it just outside the other side. 

Speaker 3: Oh, 

Speaker 2: that means it is not exactly it is not feeling the length of the tunnel through here and then you see from the other side, the specular reflection is just coming out without having any interactions or any friction inside friction free transport, 

Speaker: right?

Speaker: Right. That’s why 

Speaker 2: you’re seeing a huge flux. 

Speaker: Ah, so [00:12:00] basically when you put helium on one side inside the capillary, because there is no friction, it is accelerated so much that when it comes out, it is a hundred times the, uh, the speed at which you had expected. Oh wow. That is so cool. Oh my God. So not just that your pipe, your pipe, your tunnel is clean, but it’s also, oh wow.

Speaker 2: Yeah, something else is adding there. So because. Um, yeah, these are atomically smooth crystal planes. Correct. So they’re very, very smooth to the helium and helium doesn’t feel them as a rough road. So it’s like a light specular refraction, you know, you, for example, when you go to a nature somewhere in the, uh, in the far mountains, you could see a peaks of the mountains very clearly on the lake.

Speaker 2: Yeah, that’s kind of a specular reflection where You see the light exactly in the water surface. Yeah, but if the water is disturbed and it’s wavy, you don’t see the peaks. So that is like, um, that’s not specular reflection. Specular reflection is when everything is flat and you could see exact image. [00:13:00] Correct.

Speaker 2: The light is reflecting with a certain angle. 

Speaker 3: Correct. 

Speaker 2: Exactly it is happening here. It’s because of its smoothness. It’s, uh, Helium is going as a specular, uh, transport wave inside. 

Speaker: Oh, are we going to this particle and wave thingy? 

Speaker 2: Yeah, exactly. This is, um, particle and wave duality nature that we could simply see that observation at room temperature.

Speaker: Oh, wow. Oh my God. That is the 

Speaker 2: That is property of a material that can be probed at room temperature. 

Speaker: Oh my god, I can’t imagine why you picked this as one of your most favorite projects. Let’s put it that way Um, so okay before before we move on. I have one question So earlier we discussed that one layer of carbon atoms, which is the graphene uh, so if the height of your uh, if a height of your uh, Nanotunnel is 0.

Speaker: 3 Nanometers then it’s like one layer of graphene You So how big are the helium atoms here? 

Speaker 2: So helium atoms are, uh, 2. 6 angstroms. 

Speaker: So that is 0. 26. 0. 

Speaker 2: 26. Yeah. 

Speaker: Okay. So they can pass even with one, uh, layer of graphene, like one, uh, spacer, like [00:14:00] one layer of graphene, uh, uh, atoms as like the spacer layer, so to say.

Speaker 2: Right. Exactly. So capillary with, um, uh, 0. 34 angstroms can still allow the helium to pass through. 

Speaker: Right, 

Speaker 2: uh, 

Speaker: Okay. All right. So okay. So you don’t need to put like you don’t need to increase the height of the tunnel because the helium atoms can just pass through. Um, okay. Wow, this is so cool. This is so cool.

Speaker: Uh, okay. Awesome. Awesome. So, um, so so so so. After speaking with you. It’s very clear to me that you really enjoy the research aspect of being a scientist. But as a presidential fellow, um, there are other aspects of, uh, doing science itself, right? So what else do you like about being a scientist? Other than the research aspect and getting your hands dirty?

Speaker: Not really dirty, because we’re always wearing gloves, guys. Okay, go on. 

Speaker 2: Right. So, yeah. Um, the other side of the my role is, um, interacting with the young, um, student undergrads and postgrads in the department. Um, so we do also do a teaching some extent and tutorials and even we do supervise them in the labs.

Speaker 2: Um, those discussions, I [00:15:00] really enjoy, uh, more with the students, uh, apart from we have a lot of, you know, scientific discussion with other colleagues. Thank you. Charts. But yeah, so these two aspects are very exciting apart from me doing a research in lab. 

Speaker: Ah, okay. So the constructive conversations and the brainstorming that happens.

Speaker: Yeah. So 

Speaker 2: the interesting thing, students ask a very, very, you know, exciting questions. Questions sometimes. Yeah. Yeah, that that part I really like. Sometimes I explain them and I see the wow, uh, messing they, you know, they face that. Okay, doing something sensible. And sometimes they ask very good questions as well.

Speaker 2: That’s 

Speaker: It’s a fresh perspective, right? So that always, uh, uh, stimulates really good conversations. Uh, definitely. So, Ashok, I hope your research experience so far has been wonderful and will continue to be wonderful in the future as well. However, if you had three wishes to improve your research experience, what would you ask for?

Speaker: And I’m [00:16:00] not promising anything here. Okay. Just a disclaimer. 

Speaker 2: Okay. Right. Okay. So, um, as, as a early career scientist, I think what I really wish I want is a funding, more funding for recruiting, you know, wonderful people to work with. 

Speaker 3: Um, 

Speaker 2: do a wonderful science and again, um, a chance to share my research with, uh, people like you or even, uh, the sign, the researchers who work in my field and even to the, uh, to the, uh, uh, school children in a broader public, all these three things require only one that is funding.

Speaker 2: So I think I wish for that. 

Speaker: So funding, then funding to do cool research, like funding to recruit amazing talents, funding to do research, and third is, uh, funding to, uh, to, to, to do outreach. So basically funding. Can we just go with the fact that just funding for everything, that’s your, like, funding, funding, funding.

Speaker: Yes. Um, yeah. This is actually 

Speaker 2: for the time being. Okay. That’s my 

Speaker: next time you’re on the podcast. There might [00:17:00] be some other things, but for now, yeah, absolutely. And this is an alignment actually, because we recently, uh, completed, uh, like we reached the milestone of interviewing more than a hundred researchers, like materials and nanoscientists.

Speaker: And we did like our own analysis of the wishes the three top three wishes of the of the materials and nanoscientists and funding was like the top one like funding more funding, better funding, higher funding, always. So it’s in alignment with with with our findings as well. I hope you will get the funding, Ashok.

Speaker: This has been wonderful. But before I let you go, could you tell our listeners, Thank you so much for joining us. What can the followers, like, what can our followers, the Twitter followers expect in the week that you are taking over the Real Scientist Nano Twitter account? 

Speaker 2: Um, yeah, I think I will give a broad introduction to my research area in the first week, uh, first day of the week.

Speaker 2: Um, and then followed by, I will talk about my research journey, [00:18:00] probably some, um, Youngsters are, you know, early carer researchers probably find that, uh, a route, what kind of, you know, possibilities exist for them to excel to the independent positions. 

Speaker 3: And 

Speaker 2: then, um, following the day, I probably go into my chemistry side of the research.

Speaker 2: As a chemist, you know, how we can design nanographene and nanomaterials. And, and then, and then I’ll come back to the, uh, graphing nanostructures at these 2D, um, tunnels. Yeah. So we’ll talk about how we make these and what kind of properties that we could see, what kind of materials can go through. So I, I only talked about the helium gas going through it, but we have, uh, Other exciting molecules of materials, uh, going through are from ions to, you know, the macromolecules such as the DNA, going through such, um, 2D tunnel, and then how does it behave?

Speaker 2: So I will share that kind of results. Mm-Hmm, . And at the end probably I will talk about, um, other [00:19:00] aspects, uh, what can be done and more into interdisciplinary are, uh, a general topic into the 2D materials. 

Speaker: Okay. Wow. Oh my God. There is so many, so much information coming our way. Can’t wait to, uh, to consume everything and learn everything about the, uh, about the nanotunnels, especially like graphene nanotunnels and what all can go through.

Speaker: And, uh, this is amazing. Thank you very much Ashok. And really, really looking forward to having you on Real Scientist Nano. Thank 

Speaker 2: you Pranthi and thank you Real Scientist team for this. 

Speaker: for listening. To know more about us, do visit our website, theirsciencetalk. com, and do consider giving us a review or a rating or follow depending on wherever you’re consuming this content.Speaker: Thank you very much.

Podcast title – Graphene Nanotunnels: Welcome Onboard