Platinum for hydrogen energy. Interview with Piotr Zelenay, a nominee for the Global Energy Prize
Brilev: A warm welcome to all of the subscribers of the Global Energy Association. This is the continuation of our magnificent series with people, who've been shortlisted for this year's Prize and today we have a guest, whose name I can pronounce easily, because he's a slav, Piotr Zelenay. Although I'd imagine, Dr Zelenay, that you surname must be misinterpreted as mine in many occasions in America, where you work now.
Zelenay: My name is being often pronounced as “Elainey” we pronounce it “Zelenay”, but actually my last name is Hungarian, it's not even Polish.
Brilev: Oh, well. My problem is, that you know everyone knows me as Mr Brilev, Dr Brilev, although in Russian it is of course pronounced like “Brilof”, but I am so used to it, I don't actually correct people. Now you've been nominated for pioneering contributions, I'm quoting here: “The fundamental research technology development and commercial production of fuel cell catalysts and devices”. Now if you win and you go to that stage, the audience there, the professional one, would immediately understand what we are talking about, but for those people who are not scientists, who are not involved in this research, how would you explain in simple terms, what are we talking about, when we say catalyst in a fuel cell and why is it so important.
Zelenay: We can perhaps start with the fuel cell itself. So, fuel cell is a converter really it gets a converter for chemical energy into electrical energy directly, without being limited by the cardinal cycle, so in other words, because of overcoming that limitation, fuel cells can reach very high energy conversion efficiencies, so when the internal combustion engine can reach the efficiencies at the level of 30-40%, perhaps, in some cases a fuel cell also theoretically can reach efficiency very close to 100 percent. So, if fuels cells are capable of converting a chemical energy of the fuel, typically it's hydrogen, but it can be methanol for example, or some other fuels, which are directly electrochemically combusted within the fuel cell itself and generating electricity. Fuels unlike batteries is not an energy storage device or electricity storage device, but it's just converted. It works when the fuel is fed into it and it stops working when the fuel stop being delivered to it. That is actually a significant advantage, because there is no need to recharge a fuel cell. It's ready immediately to deliver electricity, as soon as we start delivering fuel to it. Now there are two electrochemical processes occurring in the fuel cell. Two electrodes, one is called the anode, at which the fuel is oxidized…
Brilev: Thanks for repeating the secondary school stuff, but it's important for our viewers is
Zelenay: And the other one is called the cathode, at which oxygen from air is reduced. So, the overall reaction occurring in the fuel cell is the same as a combustion of the fuel under regular conditions. However, as I mentioned before, with a very high efficiency. So, the biggest challenge, of course, and the ultimate target is to make a fuel cell as efficient as possible, which means to operate, to have the two catalysts in the two electricals to operate with the maxi at the lowest possible so-called overpotentials. So, as close to thermodynamic of the operating potentials as possible. So, the most important for future performance there are some other factors, which we cannot talk about earlier but we don't have to, is to make catalysts as good as possible for one and the other electrode.
Brilev: And that's where the magic starts.
Zelenay: That's where the magic starts, yes. So, we are talking in my case at least about so-called polymer electrolyte fuel cells operating at relatively low temperatures typically around 80 degrees. We are also talking about a hydrogen oxygen or hydrogen air fuel cell with hydrogen being the fuel. This is the most common fuel, generating the higher power densities from the filter or fuel cells stacked in larger systems. So, hydrogen is being oxidized at the anode and the oxygen is being reduced at the cathode. As far as the anode process is concerned, hydrogen oxidation at least in acidic fuel cells they could be alkaline, as well and hydrogen oxidation is a very fast electrochemical process, because it is so fast, because of the very fast kinetics. We do not need much catalyst to oxidize hydrogen. On the cathode however, we require significant amounts of catalyst, because oxygen reduction is a very slow process under electrochemical conditions. In both cases the reference catalysts they incumbent catalyst, if you like are based on platinum or it is just platinum, because hydrogen oxidation is, as I said the fast process, we require minute amounts of platinum to generate current densities required at the cathode, because their oxygen reduction is slow, we require much more catalyst platinum base or just platinum. In the practical systems these are very often platinum transition metal elbows, such as platinum cobalt for instance.
Brilev: You must have a lot of platinum cards in your in your pockets.
Zelenay: Yeah, well, right now the price of platinum is lower than it used to be in some cases.
Brilev: Yes, it is.
Zelenay: It's around one thousand dollars per ounce. But I think in the past it was as expensive as twenty five hundred dollars.
Brilev: Let me ask you a very strange question. Both you and I are from former communist countries. I understand, that you've been working in the States since late 90s, so I'll ask you a question which you immediately recognise, because I'm sure, that you have the same experience. When and where did you get your first credit card? A visa. In the states presumably.
Zelenay: Actually it wasn't a Visa.
Brilev: Or the Mastercard. Doesn't matter, I'm not going to publicise that, but you've got it, presumably, you received it, you obtained it in America.
Zelenay: In America, that's correct.
Brilev: Okay, my case was, I received my first ever plastic in the UK, after which you went home surely to Poland, as I did to Russia. And you enter a shop and you want to buy something and then you realise, that this is still a cash economy. As you will remember in the 90s very rapidly cards substituted cash, but there was this period of time when you were coming from the west with the cards and people were looking at this card realising: “Hell, this man has got the money but he can't stand it in my shop, so I must put this little machine, which reads the cards. This is an egg and chicken question, about what comes first a card in your pocket or this little machine in the shop, which reads it. I will now reinterpret this question, having in mind hydrogen. What will come first a hydrogen car or a hydrogen petrol station?
Zelenay: What will come first?
Brilev: Yes, what do you create first? The infrastructure?
Zelenay: The question often asked is what should come first. Should that be the infrastructure, that's hydrogen filling station or should that be the fuel cell itself or fuel cell car. I think they need to come together, because one cannot be with without the other. From the technology point of view, my view, I think, that the fuel cell car ultimately fuels the system was ready before the infrastructure and right now we have fuel cell powered cars as commercial products, but their inter market introduction is limited by the lack of the infrastructure.
Brilev: The reason I'm asking this question is that this video session that we're having now isn't between Russia and the United States. Well, the United States obviously being the richest country in the world etc. but Russia is also in the in the north of this planet, where infrastructure is being built, where people think about modern technologies. But a lot of our viewers right now are in the developing world. How viable? How conceivable are all these ideas not just in the rich corner of the world, but also in the South?
Zelenay: I think, they are conceivable. I think the South may have certain advantage, which we know from the introduction of cell phones for instance, where the lack of classical or old telephone infrastructure allowed the South or many southern countries to bypass the landline era , the line of the stationary family infrastructure and I think that like in many other cases it's a matter of cost. If the cost is brought down to the level comparable to generating the cost of hydrogen, especially, of generating petrol or gasoline, as we would say here in the US.
Brilev: Well, you sometimes even say gas, which is absolutely confusing.
Zelenay: This is kind of confusing, of course not for people, who are used to to talking this things. But I think once the cost parity is reached I don't think it's going to be a big problem, because at some point you just need to make a decision, with which you are committing to.
Brilev: You occupy in this research a very interesting corner, which is very important for a lot of people in the United States, in Russia, in Northern Europe, who are involved in oil and gas exploration, because the more these days they hear about the climate change, the more afraid they are of a perspective on this danger on the horizon of that solar panels and windmills will substitute the traditional thing. As far as the hydrogen is concerned there are several ways of obtaining it. You can do it in a very old fashion, which I think is disappearing – coal, or you can extract it from natural gas. Or you could even use this very modern technologies of getting it out of water, obviously, using the electricity produced in turn in the alternative energy sector. They're all sorts of these states. Well, your research is of course not about the industrial production, but you know how it works. Do you think the oil and gas industry will survive in the hydrogen era if it ever comes?
Zelenay: See, I may not have enough knowledge to answer this question. And obviously, that there is a danger for that particular industry to become less important, but also there is obviously a benefit that certain areas of energy generation will become less dependent. I don't know if that in industry is going to survive I think it as far as the source of chemicals.
Brilev: Oh, this is obvious.
Zelenay: Yes, this is obvious, it will survive. As a major supplier of fuels for cars and electricity generation etc. The importance of that in industry will ultimately become less. In many cases it has already started looking into becoming more involved in clean and so-called “clean energy generation”.
Brilev: But what about hydrogen, in particular. Do you think the major nsource of industrial hydrogen will be the natural gas?
Zelenay: Hydrogen is a by-product for many synthesis processes, and it is effectively generated from fossil fuels there is no question about. The interesting aspect of it, even though it is generated from fossil fuels the use of hydrogen allows to increase so-called “well to wheels” efficiency, because of the high efficiency of the electricity generation once you have the fuel. So, that is something, which is often not realised.
Brilev: I didn't realise that to be honest with you.
Zelenay: But the ultimate target of so-called hydrogen economy is obviously to generate hydrogen from so-called clean sources, like you mentioned and that would be obviously solar, wind or combination of the two, like pursuit in Germany.
Brilev: Well, we'll see. We are of course in a scientific question, but you know because we speak a lot with the people from the industry I feel certain solidarity. So for me…This is another question, of course, but for me the question of sustainable development is about creating new technologies and making energy more affordable and more accessible, but also about if not keeping the old-fashioned jobs than recreating them. I have a lot of friends in the coal industry here in Russia… Yes, the technologies have changed believe it or not, but in the Soviet times, in the communist times, there was more than a million coal miners in the USSR. These days in Russia there are only 150 000 and they produce more coal than they used to do in the soviet sites. Technologies change, but of course people look at coal with suspicion, but people look at hydrogen with suspicion as well. The first image that comes to an educated mind is the Hindenburg “dirizabl” as they were called back then, exposing. What do you say to that?
Zelenay: Well, the energy content of hydrogen is comparable to that of gasoline or petrol if you like in British or European terms. So, I think that in one case we are dealing with the gas, in the other case we are dealing with a liquid fuel and both have a very high energy content, especially gasoline. So, I think it's perhaps a different set of precautions we need to use with hydrogen versus gasoline but ultimately, we just need to be careful and without high energy content the fuel offeres very little value.
Brilev: Okay, I've deliberately made this conversation more understandable for wider , but now, let us imagine, that we're not being listened by wider audiences and you address your fellow scientists. I imagine that in the next minute or so the only thing I'm going to be understanding is “off”, “about”, “if” etc . And all of the words will be from outer space, but when you meet your fellow scientists what is the main challenge in your sphere of interest? What are you talking about?
What's the thing that you must overcome?
Zelenay: I probably need to pick up where we left off when we started. So, we started talking about the fuel cell and the catalyst and the cost of catalysts, because they are platinum based. Again, we are talking about polymer electrolyte fuel cells. There are many other types of fuel cells, that we can talk and talk about. The biggest challenge right now in general is the cost and it's not very surprising.
Brilev: This is understandable.
Zelenay: Yeah, and the other cost is durability of all those new systems. When it comes to hydrogen oxygen fuel cell for automotive transportation, which has been the main focus over our research here in Los Alamos filter program, which by the way has been around the longest in the world. I think it started in the early 1970s, during the first oil crisis and has continued ever since. So, the challenge is the cost, because of a precious metal involved in generating electricity. To what degree it's a challenge? So, we combine single fuel cells into fuel cell stack, containing many fuels to generate substantial power in the fuel cell car. So, the cost of platinum needed in the current automotive fuel cell system represents close to 40 percent of fuel cell stock cost. Even at that low cost of platinum I already mentioned with an introduction of fuel cell cars into the market the demand is going to drive the cost of platinum up. Increase in the volume is not going to help in this case, because the precious metal market is not subject to the economies of scale.
Brilev: Now, this is good news for Russia, which is a major platinum producer. So, go on.
Zelenay: So, what we need to do is to reduce the amount and we as community have been doing that for years now, by reducing the amount of platinum, that turned out to be very successful. To the point, that now you can buy in certain parts of the world, with some kind of hydrogen infrastructure, you can buy fuel cell cars, there are passenger cars, available in the market made by Toyota first and Honda and Hyundai now. So, one approach is to reduce uh the amount of platinum. That amount of platinum has been reduced through different means. The other way is of course to replace platinum all together with no platinum catalysts, especially at the cathode we already talked about. And this is what I am doing. How we've been doing and other peer people in the field have been doing is developing so-called non-pro platinum group metal catalyst or platinum group metal-free catalysts.
Brilev: Like what?
Zelenay: In our case this has been a carbon-based catalyst. These are catalysts, which are typically based on high surface area carbon and doped with nitrogen and transition metals in relatively slow or low quantities. But these are transition no precious metals obviously and most commonly it's iron but it could be manganese in some cases. In these metals active sites are created supposedly involving the transition metal coordinated by nitrogen, which shows significant activity in oxygen reduction reaction. So, this is the reaction which in in the fuel cell is taking place at the cathode and requires a larger quantities of platinum which drive up the cost of the fuel cell stack.
Brilev: Well, all I can say at this stage is that 15 scientists from all over the world Australia, Denmark, the United States, China etc. have been selected by our technical experts for the shortlist, which will be looked at by the International Committee on the 7th of September and the announcement will be on the 8th. And all I can say at this stage that is going to be a tough decision for the International community, because the more I speak to our nominees the more impressed I am. Well, congratulations on your research. Please stay on our orbit. I wish luck to all of the nominees, of course, we'll see, what the International Committee decides, but let's keep in touch.
Zelenay: Thank you so much! It's been a pleasure talking with you.
Brilev: Likewise. Thank you.