When looking for catalysts for the energy transition, materials consisting of at least five elements are considered extremely promising. But theoretically there are millions of them – how do we identify the strongest one?
A research team in Bochum led by Professor Alfred Ludwig, head of the Materials Discovery and Interfaces Department (MDI), succeeded in placing all possible combinations of five elements on a support in a single step. In addition, the researchers developed a method to analyze the electrocatalytic potential of each of the combinations in this micromaterial library with high throughput.
This is how they hope to greatly accelerate the search for potential catalysts. The team from Ruhr University Bochum published their findings in the journal Advanced materials.
A complete material system with five elements on a single support
For the production of material libraries from so-called high-entropy alloys, the Bochum researchers use a sputtering process. In this process, all raw materials are simultaneously applied to a carrier from different directions.
The raw materials are deposited in different mixing ratios on each side of the carrier. “In the current project, we have perfected this process by using holes in such a way that each material mixture is deposited only in a small spot about 100 micrometers in diameter on the substrate,” says Alfred Ludwig. This is roughly equivalent to the diameter of a human hair.
“By miniaturizing the material libraries, we are now able to host a complete five-component system on a single support – this is a huge advance,” says Dr. Lars Banko from the MDI Department.
Research with suspended drops
To study materials created with this technique, researchers use what is known as scanning electrochemical cell microscopy (SECCM). This involves measuring the electrochemical properties of the material at a specific point by means of a suspended nanodroplet of an electrolyte measuring one-thousandth the diameter of a human hair.
“This means that we can use high-throughput methods to identify candidates with the highest catalytic activity, where a more detailed analysis seems worthwhile,” says Professor Wolfgang Schuhmann, head of the Department of Analytical Chemistry at Ruhr University Bochum.
Using these methods, researchers hope to efficiently search through the multitude of possible materials for new catalysts to identify candidates that are particularly active as catalysts. Catalysts are needed, for example, for energy conversion processes that could allow us to use green hydrogen on a large scale as an environmentally friendly energy carrier.
Lars Banko et al., Microscale Combinatorial Libraries for High-Entropy Materials Discovery, Advanced materials (2022). DOI: 10.1002/adma.202207635
Provided by Ruhr-Universitaet-Bochum
Citation: Tens of thousands of potential catalysts the diameter of a single hair (2023, January 16) Retrieved January 17, 2023 from https://phys.org/news/2023-01-tens-thousands-potential-catalysts-diameter .html
This document is subject to copyright. Except for any fair dealing for the purpose of private study or research, no part may be reproduced without written permission. The content is provided for informational purposes only.