17-Jan-2022 - Ruhr-Universität Bochum

A treasure map for the realm of electrocatalysts

Research into promising materials is hampered by the sheer number of possible candidates: An efficient method to solve this problem now developed

Efficient electrocatalysts, which are needed for the production of green hydrogen, for example, are hidden in materials composed of five or more elements. A team from Ruhr-Universität Bochum (RUB) and the University of Copenhagen has developed an efficient method for identifying promising candidates in the myriad of possible materials. To this end, the researchers combined experiments and simulation.

Millions of systems are conceivable

High entropy alloys (HEAs) are chemically complex materials made up of mixtures of five or more elements. What’s interesting about them is that they offer completely new possibilities for the development of electrocatalysts. Such catalysts are urgently needed to make energy conversion processes more efficient, for example for the production and use of green hydrogen. “The problem with HEAs is that, in principle, millions of high-entropy systems are possible and each system involves tens of thousands of different compositions,” explains Professor Alfred Ludwig, who heads the Materials Discovery and Interfaces Chair at RUB. It is almost impossible to tackle such complexity using conventional methods and traditional high-throughput procedures.

Five sources, six constellations

The researchers describe a new method in their paper that should help to find promising high entropy alloys for electrocatalysis. In the first step, the team developed a way to produce as many potential compositions as possible. For this purpose, they used a sputtering system that simultaneously applies the five base materials to a carrier. “You can imagine this as five spray cans directed at one point on the target,” explains RUB researcher Dr. Lars Banko. This produces a very specific composition of the five source materials on each point of the carrier, so-called materials libraries. Since this composition is also affected by the position of the sources of the source materials, the research team modified them in the experiment. The materials libraries from the manufacturing processes with six different constellations of the sources were subsequently characterized using high-throughput measurements.

The RUB electrochemistry team then examined the materials libraries in this manner for their electrocatalytic activity.” This enables us to identify trends where possible promising candidates are located,” explains Dr. Olga Krysiak, who with Lars Banko is a lead author of the paper. The team matched this data from the experiment with a large simulation data set provided by the researchers at the University of Copenhagen in order to understand the composition of the materials in greater detail. The comparison between simulation and experiment enables the researchers to explore the atomic scale of electrocatalysts, to estimate the statistical arrangement of atoms on the material surface and to determine their influence on the catalytic activity.

Facts, background information, dossiers
  • material science
  • electrocatalysts
  • green hydrogen
More about RUB
  • News

    Copper is effective against Sars-Cov-2 on surfaces – silver is not

    Copper and silver are known for their antibacterial properties. Researchers from Bochum have explored their effectiveness against viruses. Silver and copper ions wipe out many pathogens. That’s why implants and medical instruments, for example, are coated with these metals. Researchers from ... more

    A sieve for molecules

    Scientists have long tried to use graphene, which is composed of carbon, as a kind of sieve. But this material doesn’t have any pores. Now, a team has found an alternative material which comes with pores from the outset. Researchers from Bielefeld, Bochum and Yale have succeeded in producin ... more

    Molecular machine in nano cage

    In cooperation with an international team at the Institute for Basic Science in South Korea, theoretical chemists Dr. Chandan Das and Professor Lars Schäfer from Ruhr-Universität Bochum (RUB) have constructed a molecular gyroscope that can be controlled remotely by light. They also succeede ... more

More about University of Copenhagen
  • News

    Reusable plastic bottles release hundreds of chemicals

    Researchers at the University of Copenhagen have found several hundred different chemical substances in tap water stored in reusable plastic bottles. Several of these substances are potentially harmful to human health. There is a need for better regulation and manufacturing standards for ma ... more

    X-ray view into hydrogen production

    Green hydrogen is expected to play a central role in the energy industry of the future: Among other things, it can replace oil and gas as energy carriers and also enable emission-free production of steel and cement. For an efficient hydrogen economy, however, the production of the energy-co ... more

    Quickly identify high-performance multi-element catalysts

    Finding the best material composition among thousands of possibilities is like looking for a needle in a haystack. An international team is combining computer simulations and high-throughput experiments to do this. Catalysts consisting of at least five chemical elements could be the key to ... more