Professor Robert Schlögl is Director at the Fritz Haber Institute of the Max Planck Society in Berlin, Germany, and Founding Director at the Max Planck Institute for Chemical Energy Conversion in Mülheim a.d. Ruhr, Germany.
He participated in the online panel discussion “Green Chemistry – Green Fuels” at the Online Science Days 2020 organized by Lindau Nobel Laureate Meetings, and, subsequently, Dr. Vera Koester from ChemistryViews spoke with him about trends and challenges in catalysis research.
Who has inspired you most throughout your career?
I had the pleasure of working together with two mentors in my early career. One was Sir John Meurig Thomas in Cambridge, UK. From him, I learned the most important phrase for my work: “Everything in science is interesting but only a few things are relevant.” I consider my job to be finding out the difference between interesting and relevant.
The other important person who inspired me was the Nobel Laureate Gerhard Ertl. From him, I learned that it is extremely important to be precisely quantitative and not chemically qualitative. This has inspired our work to the present day.
What do you enjoy most about your present job?
The interaction with my co-workers. In my view, science is people, and chemistry is a team effort. My main role is to motivate and to ask the right questions.
In addition, what I like most about my job as the Max Planck Director is that I have the freedom to choose my research subjects without having to ask for permission and grants beforehand. We can simply approach interesting science questions and see what we can achieve with our team efforts.
What kind of subjects do you think are most motivating to pursue?
Subjects that are of societal relevance. We have the luxury of working in energy chemistry, and I think energy transition is one of the biggest challenges of this century. If we can contribute by shaping the tools that we need to achieve this, then I think this is very motivating.
Can you say a few words about your current research?
We work in chemical energy conversion and want to convert electricity into a form that we can trade and store. That is essentially, in the first place, hydrogen. So we are interested in electrolysis. We are also interested in all other means of how we can generate hydrogen from other sources such as biomass or methane. As hydrogen cannot be transported very well, we want to convert it into transportable derivatives, typically into ammonia or methanol.
The common denominator of these is interfacial reactivity or interfacial catalysis.
Currently, we are about to develop a new way of how we synthesize catalysts. At the moment, this is more magic than science. We are setting up a large project in Berlin to make catalysts in the same way that we make solar cells. For this, we will put a thin film of the catalyst on a glass surface and put it in differently shaped reactors to find a more rational way to synthesize novel catalysts. The project involves about 80 people in a huge collaboration between the Helmholtz Association and the Max Planck Society.
Where did the idea for the thin films come from?
This is the result of our 25 years of work on conventional catalysts. We discovered that all industrial catalysts have a very thin layer of active material on their surface. This active layer is only formed when the catalyst interacts with its reactants. The layer is not present when you synthesize the catalyst.
Therefore, it might be a clever idea to synthesize this active layer in the first place rather than wait until the catalyst precursor material reacts with the reagents. This brought us to the thin-film approach.
So you could say it is the synthetic conclusion of what we have found analytically. The technology to be able to do this is rather complicated. It essentially comes from semiconductor science. This means that the researchers in catalysis usually don’t have access to this technology and semiconductor scientists do not use it for catalysis research.
So the project requires interdisciplinary collaboration?
It is highly interdisciplinary. This is also the reason why the collaboration between two research organizations was necessary.
How do you think industry chooses the most efficient projects from the many research projects performed by academia? Is that driven by the market, networks, coincidence?
It is a mixture of many things. I think in the end it is driven by the market because industry has to be profitable. But, of course, the market is not free. We have influences from society and also legislation, in particular, when it comes to energy.
A CO2 taxation, for example, is a very strong driver for chemical research for industry transformation because it makes energy from fossil resources significantly more expensive. That is not a problem in many industries, but it is a big problem for the chemical and petrochemical industry where energy cost is a significant portion of the total cost of the product.
That is intentional, and I think this is also perfectly fine. Industry needs a motivation to change. This comes essentially through legislation from society. What industry also needs – and which is not given today – is stability in its boundary conditions. At the moment, we see industry behaving very reluctantly when it comes to larger innovations because they are simply not sure whether they have enough time for payback. Usually, the political environment changes so rapidly and so drastically that on the timescale of their innovation cycles of 20 to 30 years, they never know what is going to happen in two years. If they, for example, now convert their structures by assuming a hydrogen-based economy and maybe in two to three years this is no longer validated, their business model breaks down.
The most important thing is that we get stable boundary conditions. Also for us in research, it is very difficult if the political targets change every four or five years as they do at the moment. And in the US system, they even change faster.
We need a more stable legislative or regulatory environment. If everybody would now agree that the time of coal is over, and oil is about to go, and the future is gas and hydrogen, if that would be common knowledge and if it would also be fixed in our legislation this would make our lives much easier.
And if we condition this stability to be there, how important do you consider hydrogen in the energy transition?
It is an absolutely indispensable part, making up 50 % of the energy transition. One half is, of course, direct electricity that we get from the wind and sun. The other half is conserved wind and sun. The phrase is: “Put the sunshine in the tank”. And this is hydrogen as a good educated guess.
What is the main challenge to achieving this?
Essentially, again, it is boundary conditions. You need a lot of infrastructure for that.
Making hydrogen by electrolysis is essentially a manageable issue. We have all the technology needed except production technologies. We manufacture electrolyzers in the same way we manufacture luxury products: by hand. This is, of course, unacceptable. The electrolysis industry is currently in the same state as the solar and wind energy industry was 20 years ago.
However, I think obtaining hydrogen is not so much our problem. The transportation of hydrogen is more of a challenge. You cannot transport gaseous hydrogen in large amounts. Transporting liquid hydrogen is also very difficult. To cool a ship down to 21 K and keep it there for one month is not so easy. It is possibly doable, but I would not choose to go in that direction because it takes a lot of energy and a lot of precious materials like titanium.
I am a chemist, so I think you take the hydrogen and convert it into a transportable form like methanol or ammonia and then you ship these around.
And to do so, you need catalysts?
Of course. Catalysis is the indispensable technology for the energy transition.
And as you said, the first-generation technology for this is already available?
Yes. Of course, there will be improvements. Think of our communication technology: The first generation of mobile phones was nothing compared with what we have today.
And I think we have to start now, rather than do another 20 years of research. Whatever is being done in research today will not save our planet because that is something that will come into large-scale operation only after 2050. The urgency and magnitude of the challenge require that we live with what we have today. We cannot rely on anything that we do not know today.
And you are following this advice, for example, with the Carbon2Chem project.
If we look at chemists in general, do you have a suggestion on how they could support this?
We have to deepen and increase our real functional understanding of catalysis. We still see today that there is a lot of phenomenological research, which means you do something that inspires you and then you discover interesting phenomena on a very small scale. You publish it and then move on to something different.
Researchers want to move on very quickly rather than stick to “real experiments”. By real experiments I mean we need a much better culture of experimentation in chemistry. We need to document our experiments much better and to complete sets of data, i.e., test whether they are scalable, whether they are realistic, instead of just publishing one or two data points and leave out the rest.
This empty database is a key issue as to why we cannot really use artificial intelligence and machine learning technologies in catalysis to understand whether we are making any progress.
So artificial intelligence would be a future …
Yes. It is an indispensable thing for two reasons: Chemistry is now an old science; approximately 150 years old. We have collected way more knowledge than any living person can comprehend. So we need to use the collective wisdom of chemistry to move forward.
The other thing is you have to find structure–function relationships. As chemical processes are multidimensional in space and time, you cannot expect that structure–function correlations are simply straight lines. They are complicated functions. For a computer, it is no problem to look at complicated structure–function relations. But to do so, we need enough data both on the structure and on the function to generate these relationships. Currently, we simply do not have enough of this data.
Catalysis is not moving as a science because it is stuck with this enormous phenomenological knowledge and most people just increase the number of phenomenological observations rather than develop ideas of how to organize it.
The culture of experimentation in chemistry really has to change if we want to organize our observations and come from observation to understanding and if we want to use artificial intelligence and machine learning. Other fields such as crystallography or proteomics understood the necessity of a minimum of experimental standardization to create large databases quite some time ago.
So why isn’t chemistry doing this?
Many maybe simply do not understand this, and to make something is traditionally more important in chemistry than how you did it.
We operate a pretty large project together with the Theoretic Department in Berlin and with BASF. There we elucidate what the minimum requirements of catalytic experiments are that allow for artificial intelligence treatment. And it has uncovered that this is quite a bit.
Catalysis is about kinetics, and kinetics has many boundary conditions and many inscriptions that we do not understand. This is the reason why if you have one data point you cannot predict what the next data will probably be. If you could do that, then you have understood catalysis. We are far away from that.
How did your interest in science begin?
Oh, that is a long time ago. Originally, I wanted to become a forestry person. Unfortunately, after I finished school my school marks were not adequate for forestry. In Bavaria, there was a very strong numerus clausus, and I just failed this.
I was advised to spend some time either studying chemistry or biology. They asked what my preferences were. At that time, I had no idea. I took a coin and decided that the number is chemistry and the figure is biology. It fell on chemistry. So there was not much career planning here. But then I got fascinated by chemistry.
Today you are the director of two institutes. How do you balance your time?
That is a good question. I honestly do not know. I try to be evenly distributed and do a lot of video meetings and shared activities using electronic communication. We did this long before Covid came so we were not very much affected by the lockdown.
And for ten years now, I have been traveling every week back and forth between the two locations. This is quite destructive to your social life, I can tell you. When the conductors on the train recognize you, that is a sign that you are traveling too much.
I guess so. So what do you do when you are not working or commuting?
I still have quite a lot of interest in forestry. In my little spare time, I do a bit of hiking.
The forest is a very sensitive ecosystem. You can see very clearly in the forest how the climate changes. In the center of Germany, the climate zone is changing in such a way that we soon will have the same climate situation that is known for the south side of the Alps. So you can imagine how it might look here in ten years. We are about to lose the forest.
Are you optimistic that human beings are clever enough to realize how urgent it is to do something about climate change?
I am an optimistic person. Otherwise, I would not choose to do research on energy transition. I am very optimistic that at a certain point in time at least the majority of people will reach this understanding. The only question is how severe climate change will be until people understand this. Will it still be reversible, can it still be controlled, or is this already outside of our control? That I do not know, and I do not want to know, because I cannot change it anyway. But what I can do is prepare my toolbox.
And we as scientists have to deliver the context for understanding and change. It is our responsibility to circulate the knowledge.
I sincerely hope we can live up to this responsibility. Thank you very much for the interview.
Robert Schlögl studied chemistry at the Ludwig Maximilians University in Munich, Germany, where he gained his Ph.D. on graphite intercalation compounds in 1982. After postdoctoral stays at Cambridge University, UK, with Sir J. Meurig Thomas and at the University of Basel, Switzerland, with Prof. H.J. Güntherodt, he carried out his habilitation under the supervision of Professor Ertl at the Fritz Haber Institute in Berlin, Germany, in 1989. He became a Full Professor of Inorganic Chemistry at Frankfurt University, Germany. Since 1994, he has been the Director of the Fritz Haber Institute of the Max Planck Society in Berlin, and in addition, since 2011, he has been the Founding Director at the Max Planck Institute for Chemical Energy Conversion in Mülheim a.d. Ruhr, Germany.
Robert Schlögl is an Honorary Professor at the Technical University Berlin, Humboldt University Berlin, University Duisburg-Essen, and Ruhr University Bochum.
Robert Schlögl’s research focuses primarily on the development of nanochemically optimized materials for energy storage and on the investigation of heterogeneous catalysts with the intention of combining scientific knowledge with technical applicability such as for large-scale chemical energy conversion.
- Otto Bayer Prize, 1994
- Dechema Medal, 2010
- Alwin Mittasch Award, 2015
- Innovation Prize State North-Rhine Westphalia, 2016
- ENI Award Energy Transition, 2017
- Eduard Rhein Cultural Prize, 2019
- Fluctuating Storage of the Active Phase in a Mn‐Na2WO4/SiO2 Catalyst for the Oxidative Coupling of Methane,
Maximilian J. Werny, Yuanqing Wang, Frank Girgsdies, Robert Schlögl, Annette Trunschke,
Angewandte Chemie 2020.
- Correction to “In Situ X-ray Spectroscopy on the Electrochemical Development of Iridium Nanoparticles in Confined Electrolyte”,
Lorenz J. Frevel, Rik Mom, Juan-Jesús Velasco-Vélez, Milivoj Plodinec, Axel Knop-Gericke, Robert Schlögl, Travis E. Jones,
The Journal of Physical Chemistry C 2020, 124, 14941–14943.
- Imaging the dynamics of catalysed surface reactions by in situ scanning electron microscopy,
Cédric Barroo, Zhu-Jun Wang, Robert Schlögl, Marc-Georg Willinger,
Nature Catalysis 2019, 3, 30–39.
- CO Oxidation as a Prototypical Reaction for Heterogeneous Processes,
Hans-Joachim Freund, Gerard Meijer, Matthias Scheffler, Robert Schlögl, Martin Wolf,
Angewandte Chemie International Edition 2011, 50, 10064–10094.
- Structure-Function Correlations for Ru/CNT in the Catalytic Decomposition of Ammonia,
Weiqing Zheng, Jian Zhang, Bo Zhu, Raoul Blume, Yonglai Zhang, Klaus Schlichte, Robert Schlögl, Ferdi Schüth, Dang Sheng Su,
ChemSusChem 2010, 3, 226–230.
- Catalytic Properties of Hierarchical Mesoporous Zeolites Templated with a Mixture of Small Organic Ammonium Salts and Mesoscale Cationic Polymers,
Feng-Shou Xiao, Lifeng Wang, Chengyang Yin, Kaifeng Lin, Yan Di, Jixue Li, Ruren Xu, Dang Sheng Su, Robert Schlögl, Toshiyuki Yokoi, Takashi Tatsumi,
Angewandte Chemie International Edition 2006, 45, 3090–3093.