Rebecca Katharina Pittkowski

Project title

Stability of water electrolysis catalysts – StabilECat

What is your project about?

Using electricity, water can be split into hydrogen and oxygen, and this hydrogen is a key molecule in the transition of our chemical industry to a renewable one. A catalyst is needed to make the water splitting process as efficient as possible. Iridium, one of the rarest elements on earth, is used for this. My project aims to reduce the amount of iridium while maintaining efficiency. Here, the stability of the catalyst is a particular challenge. In StabilEcat, we want to find out why the catalyst performance deteriorates fast when using smaller amounts of iridium. What are the processes that lead to this loss of efficiency? To understand this, we will use high-energy X-rays to look inside the catalyst during operation and follow the structural changes throughout the process.

How did you become interested in your particular field of research?

Already when I was in school, I was very interested in the topic of energy conversion and energy supply in physics lessons. I believe that this is crucial for a sustainable future and this motivates me a lot in my research. My interest and fascination in chemistry lies in understanding how the properties of a material affect its structure and how we can use this knowledge to create new materials with better properties. I combine these two areas of energy conversion and materials chemistry together in my research in the field of electrocatalysis.

What are the scientific challenges and perspectives in your project?

One challenge is that the chemical conditions of electrolysis are very harsh, meaning that only very few materials are stable, which is exactly why iridium is so crucial here. To understand the structural changes that lead to catalyst degradation and loss of efficiency, we need to study the materials under these harsh reaction conditions and understand on what scale deactivation occurs. To achieve this, we will combine different characterization methods. X-ray scattering allows us to follow how the atomic structure of the catalyst particles change. We will combine this with spatially resolved X-ray microscopy to understand which macroscopic details in the catalyst film this is related to. With this combined knowledge, we will discover what the mechanisms are that lead to the performance, so that we can designs more stable catalysts.

What is your estimate of the impact, which your project may have to society in the long term?

Durability is a key issue for the development of new catalysts. The most efficient material in the world cannot be used if it is not stable enough. Understanding the complex mechanisms on different length scales that lead to this instability is therefore essential knowledge, which is required to advance catalyst development in general. If we can make progress in stabilizing catalysts for electrolysis with lower amounts of iridium, it will be of great value for the green transition. Dependence on this rare element can put a damper on the production of hydrogen by electrolysis. But hydrogen from renewable electricity is key for the sustainable production of fertilizers, fuels, steel, etc.

Which impact do you expect the Sapere Aude programme will have on your career as a researcher?

The Sapere Aude program is a great honor for me that will open new doors in my research career. I am delighted, that I can now gather a team of talented young researchers and create a research environment that can inspire and train new researchers in this exciting field. This will give us the opportunity and the framework to dive into the field and achieve research results, that can go far beyond what I would otherwise have been able to do. Through Sapere Aude and the new collaborations in the project, I can also expand my international network and establish myself as an internationally recognized expert in electrocatalysis.

Background and personal life

I'm German and originally from the border region of Denmark, known as Sydslesvig in Denmark. But then I moved to East Germany to study, to Prague in the Czech Republic for my PhD and then to Switzerland to do a postdoc. So, when I moved to Copenhagen, it was almost like coming home, and it was also a good opportunity to finally learn Danish.

When I'm not doing research, I like to spend my free time walking on the beach, visiting modern art museums (both are wonderful to combine in the greater Copenhagen area) or cooking and enjoying good food, preferably with friends.