John's the J L for her endowed professor at LSU. He, he's also the department chair at LSU. John received his bachelor degree from LSU and then, and then received a PhD here at Georgia Tech. And John was here at an interesting time. It was at time with math. You would remember it's time the Olympics for here. And so they were interesting events going on where we were allowed into the Olympic Village. We all had cases for the village and because they split the library in the village, so they let all of us wander through the village every day and nothing of importance was done except though it did the Olympic Village. Right? John also had some interesting times here. I remember one day when John came in in the morning and he walked in with the president elect of the country of Honduras. And we sat there and chatted for a while and I received this box of Honduran cigars. And many things have interests came well genres here. And now he's here to another interesting time. So today he's going to talk to us about industrialization of electrochemical carbon dioxide reduction. Alright. Thank you Paul. Let me clip this on my mask. Lecture with a mask on at LSU some a little bit. This. Thank you, Paul. Really, it's an honor for me to be here. I was a graduate student here, like most of you about 22 years ago. And I don't know how you do TA jobs, but we had to do four hours of work every year even if we were a fourth year grad student. And they would assign us to different classes and stuff like this. But I thought I was really lucky I got the assignment to help the seminar speakers setup. And so it was my job to go get the cookies and the drinks and and all of that stuff. But the really great part of that experience was I got to have about 15 minutes working, talking with the whoever was giving our seminar in. Sometimes it was boring. Sure. But sometimes that was really wonderful. At the time that they're really old, people would use transparencies. I don't know if any of you have ever seen those, but you would use a real projector and transparencies. But we were just moving to CDs at the time. So I would be the guy that would take their CD and set it up on here so they would get their, their PowerPoint to work. And it was really fun because I got to talk to him and I got to see that they're all regular people. I got to meet several Nobel laureates. I got to meet several members of the National Academy. Got to meet the founder of lamb electronics all because of this little interaction. But that's also the reason why I thought I'd never get to come back here because I didn't think I would ever be great enough to get invited back. So it's a real honor for me. I'm at LSU now, as Paul mentioned, I've been there for about 15 years. It's a beautiful campus. You can ask Henry, can't true, one of your new graduate students, I saw him come in somewhere there is in the back. But it's really pretty campus. There's some live oaks there and as alias, most of you don't know this, but Baton Rouge was once part of Spain, so they sort of took the spanish architecture. So I'd encourage you, if you're looking at postdocs or even faculty positions, were trying to hire two faculty this year. We're almost always trying to hire to faculty to consider Elisha. A little bit of history, as Paul mentioned, I'm from Louisiana. I did graduate school here. I worked in that PEDOT microelectronics building over there. And then when I when I graduated, I worked at IBM at the TJ Watson Research Center and I got to do some really cool stuff there, mostly on high resolution displays. And then I went to Motorola and Austin, Texas and I made the microprocessors. Do any of you remember the razor cell phone? Yeah. Maybe your grandparents had one. Yeah. I helped develop that. The microprocessors that go, that went into that so far. And then we also made all of the chips that went into Apple computers. If you remember before. Apple had Intel microprocessors. They had Motorola and they are all silicon on insulator. And so I got to be a part of that. And then I went to France for about four years. And I worked with Philips and St, also doing microelectronics. But around that time, Steve Jobs decided that he was going to put Intel chips into Apple computers. And still that way until just recently. Now, Apple's making their own chips are going. But anyway, he didn't need all that horsepower that you had before to do research? I started looking at an academic positions and just send an email to our department head at LSU and ask him, are you looking for faculty? And he said yes. And I didn't interview anywhere else. I just went there. I gave my one interview and eventually they made an offer. And I still remember showing it to my wife and she said, when she saw the salary, she goes, Are you kidding? And I said no. I said this is probably a good idea. And so I went joined LSU about 15 years ago. So one thing that's really special is that my family has had a long relationship with my father came here, I think it was 946. He was an old man by the time he came here, he was like 24. He had been in Europe before this, not studying abroad but in a war. So he showed up, I think 946. And he told me a lot of great stories. And then here's a picture of me from about 1994. In one, this is my ID, but if you look at how many numbers are on here, There's 16 numbers on here. There's, there's only what, 7 billion people on Earth. Why what Georgia Tech put on 16 numbers on? I've never figured that out. And then I'm also really proud to have my daughter, he or she, she came here last year during the pandemic and never step foot into a class until this year. And she's here. So I'm really proud. So also had some great mentors from, from when you know it's Paul call. The other, some of you probably noticed in this half, gives me lots of good advice. And the last is R1, R3. So Ron is from LSU. This is a picture of him when he was at LSU. Say he certainly looks like somebody who can get you down at second base. So I wouldn't I wouldn't try to steal on him. Here's a picture from when my first daughter was born. These are all Georgia Tech grad students. Here's ball, and that's the oldest daughter. So back to my talk for a second. I'm going to talk about CO2 and how to electrochemically convert CO2 into products. I'm not going to give a really detailed specific talk. Um, I, I kinda thought about it and thought about what I would like to hear as a grad student. Rather than the technical talk, I kinda wanted to give more of an overview to give you a little bit more perspective. So this is sort of like a 35-year, a 35-year review of what's going on in CO2 reduction. You've probably seen these sorts of slides before. But every year we put about ten gigatons of carbon. This is not carbon dioxide. I need to multiply that number by 3.73 or more hint into the atmosphere. And the great thing is that the earth, the land, and the oceans can take up about half of that. But the other half adds to the CO2 that's already in there at a level of about 2.2 ppm per year. And so you would say, Well, what's the big deal? We've been going up and down and CO2 concentrations for a million years. And you'd be right, these are the CO2 concentrations for the less million years. This is when **** sapiens came. This is modern humans. So the earth has seen these fluctuations before. And then these are temperature anomalies from, from today. So we've seen this before. What's the big deal? It might be hot for a while. Yeah. Well, the big deal is since the Industrial Revolution were no longer fluctuating between a hundred and two hundred and fifty ppm of CO2. We were up to about 30, 40 by the time we got to 980, which is already much higher than that previous plot I showed you. And then today we're up around for 20. This is really uncharted waters for the planet. We've never, we've never been at CO2 concentrations. This I, this is temperature anomalies. And you can see the same sort of trend with CO2. So it's not just if you live in Louisiana and you have more hurricanes, it's everywhere. There's somewhere you have to dissipate quite a bit of energy when you warm the planet up by a couple of degrees. So what do you do with ten gigatons of carbon per year? Well, I think the first thing we have to do is stop generating so much. I lived in France for about four years and they have a lot more solar, wind and nuclear power. But I think the US needs to move in that direction. What I'm going to talk about today is using CO2 as a feedstock and renewable energy for chemical manufacturing. And again, I don't think any of these, we'll, we'll take up all of that carbon dioxide. It's just way too much. When you do like a per capita per person assessment, it's like every hour, each one of us is responsible for something about the size of a refrigerator of CO2. So this room is like 200 people. Imagine if we had to put it in a cardboard box and somebody had to come pick it up. So after the seminar, we would have 200 refrigerators at the curb that somebody we would have to move to a landfill. But because we don't see it because there's no color difference, we all sort of forget about. But it's a really big deal. I think we can stop generating. I think this will improve things over the next 20 years by about ten to 20 percent. I think we can use it as a feedstock for chemical manufacturing. Allow the products you buy every day, whether it's detergents or tennis shoes, are made out of carbon. So that's one place. But the most of it, I think we really have to sequester it. We really don't have a choice. We kind of have to put that carbon back to where it came from. Ultimately, I think we should be thinking about going negative on CO2. All of this 10 gigatons would just make us even and we would stay at that 400 ppm. But I think we need to push things even lower. And there's a great report on that from the National Academy. I just wanted to say one more thing about sequestration. Is it feasible when yet, when you ask that question, I think you can Louisiana gives you part of the answer. This is injection of produced water. So whenever you take oil or gas out of the ground, you always bring some water with it. And that's called produce water. And it's usually Briony. It's saltwater. And we reinjected every everything that we pull out, we re-inject it. If you look at this, this is what's reinjected in Louisiana and deep wells. And it's 0.04 gigatons of CO2 per year. And this is the total about point, I think it's around 0.1 gigatons of CO2 a year. So if you convert that into carbon, it's about 0.03. But my point by showing you this is to show that it's, it's feasible to move this number by ten or say. So imagine you move this by a factor of 10, just in Louisiana, you begin to have some significant number relative to that number. So is it doable? Yeah, I think so. I think all of these things need to need to happen. So I'm going to talk about this one the most and the stock. So if you're talking about conversion, I think you need to talk about, think about which products and how do you use renewable energy. And when you talk about products, the main ones that I'm interested in or methanol, ethanol and ethylene. There's lots of other derivatives that you could make from these chemicals. But these, these are well-known commodity chemicals that are feedstocks for a lot of other things. If you have an endergonic process, you can use an electrolytic driving for. So instead of temperature you use potential. So this is a much lower entropy. I don't know if you guys talk about exergy. But in terms of exergy and entropy, you're much better off using energy in this way, then you are just for heat. If you can get energy out of the system, you can run a galvanic cell and you can actually pull electricity out of the reaction and use that for whatever you need at home. There are lots of opportunities here, but they have big challenges. And challenges are things like selectivity, efficiency, and rights. So I wanted to walk through a very common product that you're all familiar with. Type pot. So this is something that all of you use, but you never really think about how did it get here. So if you look at a tide pod, it's about 20 grams, about two grams of detergent, and it's about $0.20. In the surfactant in there is usually an alcohol it oxalate are this sodium lauryl sulfate? This isn't like 99 percent of the shampoos. Levi take a shampoo bottle. When you go home and you look at it, you'll see this name. But it's this ethylene oxide sorted here in the backbone. In both of these is the main thing that it's made from. So where did the start? But I didn't want to go all the way back to the Big Bang, but I tried to get back pretty, pretty far. This tide pod started out as carbon dioxide, water, and sunlight. Somewhere between a 100 million and five hundred mils a million years ago. And then something living turn this into a carbohydrate. And then it was buried. And then you have this geologic formation of coal, crude, and natural gas. Natural gas is mostly methane, but with a little bit of ethe ethane at a high temperature. And this is, this is sort of, I'm trying to do time here and temperature here, but this is not to scale obviously. So. The first thing you do to make Tide pods is you take the ethane out of the natural gas, gets what you have to use cryogenic temperatures to do. Then guess where you get the energy to make cryogenic temperatures. Where do you think? Ebay and more methane. So we make more CO2. And then after we separate the ethane, now we're going to heat it up to make ethylene because we're not very good at, are ethanes not very reactive, but ethylene, that's, that's great. So we're going to warm up that ethane to, to about 900 degrees to make ethylene. This is called a cracker. There's about 20 of these in Louisiana. They're about $3 billion each and they make tons of chemicals. And so we make ethylene. Guess where we get the energy to. To make that high temperature reaction, we burn more, more methane. And now we've got to separate the ethylene. Again, we go back to cryogenic temperatures. So we haven't gone very far since nature stop making this. And we've already seen cryogenic temperatures twice to make a Thai baht. So we separate the ethylene. Then, then we go back again. When we make ethylene oxide within 25 miles of LSU, we make about 3 billion pounds of ethylene oxide per year. So if you've washed your hands yeah. You've washed your hands. Iv use products that were made right there and Louisiana from ethane. Or if you use Tide pods. And then we make an ethylene oxide, and then we quench the ethylene oxide and we've got to cool it off again. It's not cryogenic, but cooling takes a lot of power. Usually a COP on these things is three or four at best. And then we have to do, and if oscillation reaction to make this sort of thing, we got to heat it up again. Then we quench the ethoxy. Then if you want to make this thing, you've got to react it with the OEM or some sort of SO3 to give you this detergent. So that, that to grams of detergent cost about ten times more. That's just a rough estimate. Co2 or carbon that we put into the air just to make that tie pie. And when you look at this, that whole process, this is the long as the rate limiting step. So about 500 million years. These, these are like 30 seconds or so. If I put them all together and make it two minutes. But the whole idea is why don't we just skip all of this stuff in at least go from here to here using it electrochemistry. So the question is, can we make products like ethylene from CO2 water in renewable energy? And I hope the answer is yes, this is an HL or a typical electrochemical cell. You have an anode over here. So you can essentially think about this as a reverse combustion. So no matter what you burn, you're going to make CO2 and water, whether it's crude or whether it's any organic or even a chicken sandwich. When you're, when you're going downhill, you're always going to make CO2 and water. But the question is, what if you go uphill? If I put energy into that system, what I, what am I going to make? Well, the first thing you do heart, the first thing all of you should do is look at thermodynamics. It, oops, sorry, I'm going too fast. If I, if I look at thermodynamics for this, again, we're looking at potentials instead of Gibbs energy, delta G is minus NFA. If you look at this, here's the hydrogen evolution reaction and we say, well defined, this is 0. And so the first thing that, that should happen, if you look at all of these, we should, we should make methane first and then we should hit the hydrogen evolution reaction. And then after that we might make CEO or some other products. But this is interesting. This is telling us we would make methane if we do this. It's also interesting that says that we're competing with HER. And if you think about a soft drink or something that has carbon dioxide in it, it's got a whole lot more water and it does carbon dioxide. So this is going to be a big challenge of competing with the HER. So that the products depend. I keep doing that, that the potential, they depend on the potential the electrodes, the electrolytes, and the interfaces. For, for about a 100 years. The only products, and these are at tin, lead and gold electrodes were hydrogen, CO, and formic acid. So this wasn't very interesting until 1985. So 1985, the seminal paper came out from Professor hoary and Chiba University in Japan. And he showed for the first time that you could make hydrocarbons like methane. So this is a really a game changer. This lesson, it's methane was form an appreciable amount and a copper cathode. If you read the paper, he also talks about some products like methanol and ethylene. But this is really a big deal compared to CEO or hydrogen or even for me. So this is where I picked this up by. I heard a seminar. It was that an ECS meeting that John Newman gave? I think Newman, that's what Stanford. John Neumann. Yeah, I think he's at Stanford, Berkeley, sorry. But he's retired, but he gave a wonderful seminar and he showed that paper. And I never really thought about that. And I thought, hmm, seems like this is going to be interesting for awhile. Maybe, maybe I should try to, to do some of that work. Maybe I should try to see if I can make products other than methane has, methane is pretty abundant. But if I can make methanol cheaper than you can make methane, or if I can make ethylene or if I can make ethanol. Those have a lot of value. So I started out looking at different forms of carbon instead of just using copper foil, sorry, copper. Instead of just using copper foil. There's a lot of interesting things happen when you oxidize that copper first before you try to use it as an electrode. So I tried several different oxidation techniques and this is about ten years ago. I oxidized in air. You just set it down on air on a bench top and heated up. I anodized it by making it the anode, an electric chemical cell. And then also found some recipes that are allowed me to electro deposit to cover one film. And you get these beautiful 0100 0 cubic structures here. And then I used all three of these to see what products I would get. And I made a lot of hydrogen, but I made an appreciable amount of methanol instead of methane. So I thought that was really interesting that everything else makes methane, that copper when we're making methanol. And when you look at the, at the trends here, this electrode deposited copper, one species gave me a yield that was much higher and methanol and also a fair day efficiency. Faraday efficiency is the percentage of electrons that goes to the reaction that you, you want to happen. So this was really interesting and spurred a lot of other research. We wondered why. So we started to look at, well, what happens before and after the reaction. So this is, I think this is before the reaction and this is after the reaction. So before we have more OJ spectra, we have more copper one after the reaction. Of course we have it at a negative potential. So we're going to be reducing some of the copper at the same time. So we reduced a lot of the copper and copper 0 and then the anodized. It's the same story. You see this copper 0 peak showing up over here. The electrode deposited had tons of copper one. I didn't have it here. It was it was difficult to get or impossible to get. But this state, copper one the longest. And so when you go back and look at these, you see the one that stayed, the copper one the longest really gave us the most methanol. So there's something special going on with copper 1. So we were working in a center with Majdanek and urbanistic area and they, they helped, tried to explain what was going on here. And it was really interesting. And they came up with this toolpath mechanism that everything they believe goes through carbon monoxide. So before you make anything else, people believe that you have to make carbon monoxide. And in that scene in the potential and several other things. But in this path one, what they talked about is really where that first hydrogen attacks. If the first hydrogen attacks the carbon, they believe it goes through this sequence and forms methanol. If the first hydrogen is attached to the oxygen, and you would think this one would give methanol, but it's the opposite. It gives you methane in ethylene. So we started thinking about this as like, okay, let's see if we can control this one step right here. If I can sort of force this hydrogen to go to the carbon, I can, I can make all the ethanol I want. If I can force the hydrogen to go to the oxygen will I can make, I can maybe make ethylene and I can focus on this step a little bit more. So we started working on that for, for quite awhile. And with methanol must have, most of you may know, but whenever you do methanol synthesis reaction, you do it with copper and zinc oxide. This is the most common catalysts. And it sort of makes the copper look a little bit like an oxidized form of the copper because of that, that strong oxide underneath. And so we tried to do some things with With this zinc oxide as a substrate and we would put the cover on top of it. And what we saw is that are in the best cases, our current densities for maybe, okay, they're not that great. It was not a great electrode. But what we saw is that we're still making mostly hydrogen. And I think that's coming from the zinc oxide. But then when you begin to see our products diverge a little bit. We were making about 10 percent methanol. We were making, I guess it's about 10 percent ethylene and some other products there. So this was interesting, but it's, it's really hard when you're looking at micro molar quantities of things. Not what you want to do when you're running our reaction or when you're studying a reaction. But always thought this was interesting and gave some insight that, that, that copper, when it's partially oxidized. There's something special about that. And I'll come back to them. And then a few years later, most of you heard of Norse god, does a lot of DFT modeling. He and Andy Peterson Andes at Brown now. But they did this great work and they were trying to figure out, is there a metal better than, than copper and said this is the binding energy for SEO. And so these metals, when you use them as electrodes, you produce a lot of SEO. And here, these metals are kinda poisoned. So it's sort of the Goldilocks theory that these metals hold onto CEO far too much. And these are not very well in produce CO, and these hold onto CO2 far too much and copper was near the optimum. And if you look at this, this is the potential between all of these interesting products, whether it's CHO, CH2O, COOH. It's really telling us that we can't really find a better metal than copper. So if you're working with copper fine, but don't you're not going to give it. So he really said that you're going to break the scaling relationships. You need to think about structure. You need to think about alloys of copper or interfaces. And if you think about it, that's what a treat us right? Tree takes carbon dioxide, makes a pretty complex carbohydrate. And they're not using copper, they're using excusing nickel and iron at a very nanoscale, maybe a few atoms. It's also using ligands and it's using a unique structure. Say, I think that's what this is telling us. So we started looking at very low coordinated sort of electric headless. These are things like the smallest we could make was with gold and you can make something as small as 13 atoms. So this, this came from another group, but that showed that this nanoscale materials, even though they're making CEO had really great activity. They had great fair deck efficiencies, and they had pretty high current densities over here. So this was really interesting that tells us that there is some value at looking at nanoscale when it comes to reducing CO2. So we started looking at these magic number nanoparticles with gold. And they're stabilized by these the sulfur atoms where you have thiol ligands. And so we would mobilize these on Carbon Black and we would use Nafion or PVDF binders. Both are fluorinated binders. This is the PVDF. It doesn't have the sulfonate groups on there. This is what you would use in a PM. This is what you would use in a battery. But we made these nanoparticles and we begin to look at that, the different ligands and the different binders and tried to understand what was going on there. But it was really interesting. When we have the we have that gold. This is gold with the Nafion binder, this is gold. The PVDF. You can see that the binder had a really strong effect on our fair deck efficiency that we're getting outstanding Faraday efficiency with the Nafion and what the PDA, PVDF, even with the same electric catalysts, it's not as good. We also saw that the potentials are shifting in the right directions. It became easier to do reduce CO2 when we had nanoparticles easier and when we had Nafion harder when the particles were, were larger. Also more difficult whenever you have PVDF. It would also suppress the HER. So this is all telling us that nano is going in the right direction to suppress the HR and to improve CO2 reduction. This is XPS and UV Vis of the changes in the nanoparticles. And this is a really interesting, but essentially it would tell us that these, I believe this is pre reaction and post reaction. That the Nafion sort of help keep that golden, something that looked more like a gold one state. So again, this partially oxidized metal was more active than, than the one that was in the fully reduced case. All right, so then we started wondering, well, what are these interfaces? What are these interfaces do and how do they work? So we started looking at. Just ligands. These are different. Ligands are kept to propanoic acid. They're paired in ethanol. Ethanol amine are kept in and system mean in. Instead of just using nanoparticles, we would just use these on gold foil. And we would modify these electrodes different ways and see what happens whenever use these modified electrodes for CO2 reduction. Now your first thought, especially if you're reviewing this paper for the first year, I tried to submit it. Was these things desorb whenever you apply a cathodic bias and they come off. But seen a presentation from Professor about Elliot Houston that showed that these things stick around. Even if they dimerize. They don't go very far away. And the heavier they are, the more they have an aromatic or something like that on there that they like to stick around. And so I'm not exactly sure if they're stuck to the surface, but they did have an impact on on CO2 reduction. And so what we would see is that the, the ones with this species, this Pm gave you a caveat decrease in the SEO efficiency in the increase in formate. So you put this one on same electron. Now you're making tends to form a. And then when you do the MPA, them are kept to propanoic acid. It slows down everything except for the HER. It kinda makes sense. This is a little bit more acidic, but look at that, HER kicking off with that interface. So the system mean it gave you a two x increase in CO and hydrogen yield made it more active. How did that happen off from the interface? And it sort of suppress the theremin. It's sort of suppress the form eight. So this is telling a little bit like nature that the interfaces around those catalysts influencing the, the reaction products. And so what we thought about a lot of this has to deal with like our hydrophobic or hydrophilic it is in terms of shutting off the HER. But we also thought that we maybe are changing the mechanism. For example, when you have this MPA species on here, maybe what we're doing is splitting, how we do the electron transfer and proton transfer. Most of the time in electrochemistry, electron transfer and proton transfer happen at the same time and close to the same place. Nature does a better job at separating that. But when we have an electrode, we don't do a very good job. But what we think that may be happening is that we're sort of separating the proton and electron transfer in this ligand is giving us a way to do the proton transfer out here and helping us make this formate in this case. So a little bit like nature, we can control the products. The other thing was alloys that we begin to look at and say, this is the binding energy for SEO. And so here's copper here. The real challenges I had problems making cover nanoparticles, but gold were really easy to make. As a compromise we started looking at, well, let's look at this copper gold alloy and see how does that work. So these are, these are nanoparticles that we made of copper, gold and we debate different difference amount of copper and gold, something like 25, 75 and vice versa. But it was really interesting. What came out of this? One? It was a lot of SEO and that was pretty good fair deck efficiencies. But the yield is what really look great. This is copper. This is gold. This is what happens when you do an ally. So it's really amazing your activity went up, doubled, triple or more. But you really didn't change your products selectivity. It just acted like a better version of silver or a better version of gold, I should say. So these are the two nanometer, this is the six nanometer. This just says that smaller is better, which you might expect. And it still shows pretty good Faraday efficiencies. To higher goal results in higher selectivity for SEO, but not necessarily higher yields. So we begin to compare this with foils. And what we saw again is that the nanoparticles were much more active. If you look at these onset potentials, I would like for them to be as far to the right as I can. And if you look at this, the six nanometer shift some quite a bit further back to the right. And then the two is even further. It also shifted the, HER potential in, in this direction, which is really positive. So again, it's told us that nanoparticles were the way to go. Just to recap, 1985 horror. He said that copper yielded methane at high rates. That oxide derived copper is really interesting. It's more active and produce more methanol at neutral pH is we looked at zinc oxide substrates, also gave you a little more methanol, but they really didn't give you the high rates that you would want and the copper oxide, It's really weren't stable. So we looked at the scaling rules on that Andrew Peterson published about. And then we looked at the selectivity, changing that selectivity using a binder and ligands. So turning off the HER, trying to turn on these other reactions. And the results of that showed that copper, gold gave you higher rates. But it's still act like goal. So the question is, is how do we produce alcohols and C2 products at high rates? And something that I didn't think about very much was the electrolyte. I had been using a neutral electrolyte for years. And the reason why I use the neutrals, because if you made an acidic, you would favor the HER. And that didn't make sense. If you made an alcohol and you would just make carbonates whenever you put that in there. And then you also have mass transfer problems with the with the carbonates. How do you move that much? Carbon dioxide? I think it's one of your seminar speakers recently, Paul canis was here before me. Yeah. Paul publish this paper, I think in 2017 where you use this, he use these gas diffusion electrodes. And so that was a real breakthrough. They've been used in other places, but never in CO2. And he used an alkaline electrolyte that I thought maybe that may not work. But it turned out to work very well. He was able to use these copper nanoparticles. And you see there's sort of all clustered together. They're not perfect, but they still, they still work pretty well. But I think this was a breakthrough. This was not that long ago, 2017 or something like that. And look at these fair deck efficiencies for now. Whenever you take away that HER, you're not competing to make hydrogen. Even the methane is sort of suppress. And it gives these intermediates time to get together and make more interesting things like ethylene and ethanol. Remember this is the precursor for your time. And look at the Faraday efficiency. It's around 40, 50 percent. But also look at these current densities. That's about over a 100 milliamps per square centimeter. You're starting to get something close to its industrial. So a core alkali plant will run current densities about this number, about two or 300. They use amps per square feet. I use milliamps per square centimeter. But these are getting closer to industrial numbers to actually manufacture products using this kind of technique. Another huge breakthrough, this is just, I think a year and a half ago that sergeant and Canada publish this. He did something really interesting. He put in on him or coding on the cover. And this really change things. So let's see if I can explain it here. If you look at Paul kinesis were previously he would take the carbon dioxide gas, needs to meet with the catalyst and needs to meet with the reactants. And all of these need to come together at these points to give you the product you want. And because you have this electrolyte, you always have this competing reaction. So what's Sargent did is put on this, this Nafion in the Nafion has a hydrophobic and hydrophilic parts to it. So if you think about carbon dioxide, it's not very polar at all. So it's transferred, it's transported really well in the hydrophobic parts of this. And so it allows him to use much more of this catalyst and push more, much more carbon dioxide. It also allows him to block the water so he could prevent the, HER reaction. So he was the first one to get over one amp per square centimeter. So this is just outstanding. This, this is some of the highest numbers I've ever seen. And this is the loading of this sort of ionomer and that he put on there. And he was making C2 products. These are the numbers for C2 products. This is the number for ethylene. Again, core alkalis probably in here somewhere. So now we're starting to get a lot closer to something that could be industrial. But typically you wouldn't and your paper talk about the problems. He didn't talk about the energy efficiency was something less than 20 percent because he had to use a high voltage. He pushed that like five volts or six volts, which is crazy. That's a lot more than the thermodynamic minimum. The other thing he didn't talk about is a CO2 pump. And what do I mean by that? So if I put CO2 and alkaline environment, I'm going to make carbonates. And it's, it's gonna take two hydroxides to make this one carbonate. And this is going to happen pretty fast. So another way to look at this problem, and let's say you have this electrolyzer over here. And I feed, I feed, sorry, I feed CO2 to this thing in two ways. I phi2 here and six here. Well, because I made 12 OH, over here, I'm going to consume six of my CO2 in this reaction. I'm going to consume to what my CO2, so in this reaction. So, so what? Well, that CO2, I gotta do a charge balance. I have to oxidize something. So over here at the ANA guess what? Guess what I oxidize, guess what I may. I make more CO2. So I'm spending most of my time, most of my wheels spinning my wheels. Just pushing CO2. Get used to this pushing CO2 from this side to this side. So I'm spending a lot of energy just moving this CO2 pump. And I spent a little bit of the energy doing this. If you're making CO2, the maximum conversion you can get on a carbon-based, this is 50 percent. And then for ethylene is 25 percent that I'm showing you here. Two to six or two to eight total. So this is all just recent to a collaborator from the University of Delaware figured out in an elegant way to fix this CO2 pump thing. Jiao. He said, Well, I'll just do this in two steps. I'll take the CO2 and I'll make CO and a non alkaline electrolyte. If there's any CO2 that I'm not converting, I'll recycle that. And then I'll send all the CO2 over to the copper electrolyzer that's in the alkaline and that I can avoid the CO2, the formate formation. And I make the, make the C2C products this way. So effectively I just add a recycle in a two-step or a cascade sort of step to this process. And he also talked about even if I just make the CEO, there's some, instead of using this process, there's a lot of low temperature Solid Oxide and electrolyzer is that work at a much lower potential than this. So maybe it's better just to make CO or make a form a syn gas. And this is a picture of his lab. If you look at the first electrolyzer is here and the second is here. But he solved this carbon, this carbon dioxide pump problem just by doing some smart chemical engineering, just the recycle, separating in two steps in doing a recycle. So that's the conventional one. Another solution of this came from Thomas Schmidt at ETH. And he said, most of these have an AM and an AM is Anna exchange membrane that allows hydroxide, but it also allows carbonate to pass through. So Pocahontas was using an AM. Everybody was everything that she saw before had this am in-between. There's separate the anode and cathode. For Thomas Schmidt said, well what if you use a BPM and you put the AM towards the CO2 reduction side and you put the, the CMB towards the, towards the anode. Well, in this case you're not going to, any hydroxide you sent across when it hits that interface is going to make water. Any carbonate you send across is going to make CO2 and get recycled. So I thought this was a really elegant solution. And this is only like two years ago that, that this came out. So it's really, it's really something. You also look at his sort of stability. This is time and this is current density. And if you look at this, I think this is eventually I'll get this. You look at his for the higher potential and you see how it's tanking over there with the current density, I went from a 100 down to 10. That's not industrial. All right, so this is one of the big problems. Also when you look at the energy efficiency. This is the anode potential. This is the potential that's eaten by the interface or that, that bipolar. But look at this cathode. When I tried to run at high current densities, I'm paying a big penalty in potential. And so when you add this potential with this potential, you get the overall potential. Now remember, the thermodynamic potential for this is something like 2.5 volts, something like that. And I'm pushing it six. So Usher, I'm wasting a lot of energy that I'm not going to get back when I want to run at high current density. So the two big issues that I think are still out there. We can make the right products. We can make them at the high current densities. But our energy efficiency and our durability really aren't where they need to be. But those are engineering problems. Those are solvable. So I started working with a professor at LSU, Chris Argyris, to look at our version of a BPM and we started looking at liquid for your purchase. So all the ones before had some liquid electrolyte in there. Chris is working on these membranes that they need water vapor but they don't need liquid. So if you're, if you are at Shell or DOW and you want to process, you really don't want liquids floating around everywhere. You'd really like to offer eight all in the gas phase. And so he made these bipolar membranes and we would feed them either CO or CO2. Look at the products, either CEO or ethylene, our ethanol, and we would use silver, our copper electrode catalyst. And he wouldn't, he wouldn't push pure water. He would always put a good amount of nitrogen in their needs would be run at about ADC. But this is really interesting. This is silver nanoparticle showing and you would get carbon monoxide. But this is really exciting that we saw these high current densities at moderate potentials. And then we tried this with copper and we saw similar behavior. It's not as good as making CEO. This is really interesting. It's a bipolar interface. High temperature, no liquids. So I think this is another step. We haven't published this work yet. But I think we're getting closer and closer to something that's industrially viable. So to summarize, we've made significant progress in CO2 over the last 35 years. Copper, copper nanoparticles in this oxide derived cover that started working with 12 years ago. Those are still the most interesting electric catalysts. The interfaces and the cell designer important week we can get to high current density and high selectivity to ethylene. But we have challenges. We do this cascade approach, that thing Jiao came up with. Should we do this BPM approach that Schmitt came up with? The techno economic analysis that we need these things to last for about 20000 hours. That's a long time. I think the biggest numbers you've seen, even with the carbon monoxide pump problem are around 2000 hours. So we're still an order of magnitude off on your ability. And then I talked a little bit about energy efficiency. The energy efficiency today is around 20 percent. The anode is a problem. You've got to run the OER. Lot of times it's iridium oxide has none, not the greatest thing in terms of efficiency. And then at the cathode I showed you that running at high densities cost you high potentials. But at the end, I do think you could make a significant impact on CO2 emissions. I don't think it's all I said, 10 gigatons every year. Most of it I think we have to sequester. I don't think there's any question about that, but I do think it would be nice while the planet is heating up. If I still had Thai Baht. If it would be nice if I still had finishes and it would be even better if I made those out of CO2 rather than making those out of ethylene and 500 million year process. I think that demand for carbon products isn't going to change. Think this when you combine CO2 feedstocks with renewable energy, is a double win. So instead of if I, if I sum up all the carbon products in the world every year, it's something like half a gigaton a year. But I think I would, I would get the advantage of about one gigaton just from the energy savings of using an electrochemical driving force rather than temperature. So let me stop there and acknowledge all the people who really did this work. These are my students and postdocs. This is calendar shot. A lot of the work you saw today was saying Vin Peterson, he he did a battery project. This is the new undergrad. Grace has been working on methane, but most of the stuff in here was also done by Evan Andres. I have a lot of collaborators. There's a lot of these are at LSU. Chris artists just left LSU. And then I recently started a new project to focus on those things that I told you about durability and energy efficiency with these collaborators that Delaware, who I think are some of the best in the world at what they do. So I'm really excited that I want to thank my sponsors, Intel us or see, the NSF is funding this this larger project, the DOE and the Louisiana border regions. So with that, thank you. Sure. Yeah. I think at this point I'm more interested in those polymers. So there's something called a 0 gap for perch where you sort of stick the electrolyte on the polymer. And so that interface I think is the most important when looking for. I think what we're looking for and the ligand side is more fundamental, is what specific functionality gives you, what specific reaction behavior. And some of these, I expected a lot of these to be just like a coating of oil that anything you would like if you, if you think of conventional catalysis. And I told you I was going to put something that had an aromatic on there. You would say this is never going to work. Yeah. He poisoned all of the sides. But for an electric heater, since it's low temperature, you have a lump. It's more like nature. You have a lot more functional. So I think it's more fundamental to study things. I don't think it's something that you would use to manufacture, But I do think it's important for the polymer ionomer metal interfaces. I think it has a big effect on selectivity. But there's a lot of engineering. You need to have good CO2 transport. It needs to be hydrophobic, so it kicks out the water. I think there's probably still research you can do to figure out how to give you more ethylene rather than less ethically. But, but ours, two parts. One is fundamental and the more applied, I think it's the polymer metal interface rather than the ligand that you stick there? Yes. Yes. Well, where does that precipitate? Precipitate on the electrode, that's sort of an issue. Or in those polymers it's sort of an issue. Some people had done that they would add hydroxide to keep it from precipitating. You've got to think of the CO2 penalty you pay to make hydroxide. Yeah. But, but yeah, carbonates aren't so bad if you could bury the carbonate somewhere, but we really want to process that's ideal that you stick in CO2 and water and energy. And you pull out ethylene and oxygen rather than dealing with a whole lot of carbonate. Yeah. I've only seen a few studies on that. The activity goes up, but usually solubility, it's not as good. So yeah, I think you can. The one I showed you that Chris did without the temperature, I think a lot of that was coming from temperature. I think in the future That's why I like the, the liquid free is, I think it's I think it'll give you the activity advantages you want without hitting the durability of the polymer. Thank you.