"I am particularly interested in the molecular structures and behavior of molecules at interfaces - whether in water, surfactants, lipids or polymers. My research focus is in the field of water at interfaces and is for example relevant for understanding reactions occurring on clouds in the atmosphere and for electrochemical processes. Moreover, the topic has partially grown historically," says Ellen Backus.
At the Max Planck Institute for Polymer Research in Mainz, where she had been working since 2012, her research group was devoted to water at interfaces from the beginning. As group leader, she mainly investigated the structure and dynamics of water at interfaces using (multidimensional) sum-frequency generation spectroscopy. In 2013, she received a prestigious ERC Starting Grant from the European Research Council for her project on "Fundamentals of photocatalytic splitting of water", funded until 2019.
Overall goal: "To find efficient sources of energy"
In her ERC project, she touches an important topic for the future: great hopes are pinned on hydrogen as an emission-free fuel. Hydrogen is already being used in fuel cells. However, its production is relatively polluting and cost-intensive.
"One of the drivers of our research is to find new, ecologically clean and efficient sources of energy," says Backus. Photocatalytic water splitting has great potential here. However, the basic features of the process, in which water is broken down into hydrogen and oxygen with the aid of photons (solar radiation) and a catalyst, are still poorly understood. According to Backus, it would be far too early to think about applications right now.
Observing the reaction of water molecules
"It has been known for some time that hydrogen can be split at interfaces with a catalyst and irradiated with solar energy. However, we hardly know what happens at the molecular level. That's what we want to find out." What is the exact reaction path from water to hydrogen? How do the molecules behave during irradiation, how do they rotate, how do they interact, which intermediate products are produced? How is hydrogen produced? Ellen Backus uses titanium oxide as a catalyst for her basic research. She activates the titanium oxide with laser pulses and observes their reaction at the interfaces over time with surface specific vibrational spectroscopy.
"In order to obtain efficient catalysts for the cleavage of water, we must first understand what happens at the interfaces on the molecular level. This understanding could then help to develop better catalysts for photocatalytic water splitting," says Backus.
Vienna: "Everything is pretty new"
In the winter semester, the physicochemist will start teaching with a master's lecture on interactions of soft and solid matter at interfaces. In addition, she is looking forward to the manifold points of contact in research with the other institutes of the faculty, for example in the field of catalysis (e.g. in the development of catalysts), analytical chemistry (in the understanding of the structure of molecules) and biophysics. She would also like to continue her research on the structure of ice at interfaces in Vienna, e.g. in cooperation with physicists of the University of Vienna.
Apart from her main research areas: "Vienna is completely new to me. I have not had yet any research collaborations with Viennese colleagues and have never spent much time in this city. But it is a beautiful city! And I've often been on vacation in Austria," laughs Backus, who travels by bicycle from her home to university. Welcome to the Faculty of Chemistry!
- Ellen Backus, born 1978, studied chemistry at the University of Amsterdam and completed her doctorate at the University of Leiden. She worked as a post-doc at the University of Zurich, then at the FOM Institute AMOLF in Amsterdam and since 2012 as a group leader at the Max Planck Institute for Polymer Research in Mainz. In 2013 she received an ERC Starting Grant. She is Professor by special appointment of Non-Linear Spectroscopy of Surfaces and Interfaces at the University of Amsterdam and since 1st of October Professor of Physical Chemistry at the University of Vienna.
