ICREA Prof. María Escudero-Escribano has Participated in International Research that Helps Understand the Catalytic Activity of High Entropy Alloys (HEAs)

by Jose M Arcos

This publication could aid in the advancement of the use of HEAs for renewable energy conversion. Furthermore, it demonstrates the importance of understanding the structure-property relations of these materials to address current environmental and scientific challenges.

A collaborative study in which ICN2 and ICREA researcher Prof. Maria Escudero-Escribano (leader of the Nanoelectrocatalysis and Sustainable Chemistry Group) participated, was published in the journal EES Catalysis. This research also included the participation of scientists from other institutions, such as the University of Copenhagen, the Indian Institute of Technology Kanpur, and the Technical University of Denmark. The authors combined electrochemical methods, surface-sensitive characterisation techniques and theoretical calculations to evaluate the carbon monoxide (CO) oxidation performance and the structure-property relations of a HEA electrocatalyst composed of silver, gold, copper, palladium and platinum (AgAuCuPdPt). Research on this type of catalyst could be important for finding more sustainable energy solutions in the future.

The importance of HEAs

High entropy alloys (HEAs) have been a significant advancement in the field of catalysis in recent years. These are alloys of different components with an approximate equiatomic composition, which means that they have the same approximate number of atoms of each element.

HEAs possess significant potential as catalysts, for instance, in the performance of electrochemical reactions involving the electrocatalytic conversion of small molecules such as carbon monoxide. This is a key reaction in sustainable energy conversion technologies such as low-temperature fuel cells.

In this study, the activity of the AgAuCuPdPt HEA electrocatalyst was compared to monometallic, bimetallic and other multimetallic surfaces. It was shown that the presence of silver (Ag) can enhance the oxidation of CO and that gold (Au) segregates on the surface.

In summary, HEA electrocatalysts are very promising for designing more active and selective electrocatalyst surfaces for renewable energy conversion. Advances in the research of such materials may prove crucial in developing effective solutions to environmental, energy, and sustainability challenges we currently face.

Reference article

Salinas-Quezada, MP; Pedersen, JK; Sebastián-Pascual, P; Chorkendorff, I; Biswas, K; Rossmeisl J; and Escudero-Escribano, M. (2024). Toward understanding CO oxidation on high-entropy alloy electrocatalysts. EES Catalysis. DOI: https://doi.org/10.1039/d4ey00023d.