Credit: Julia Schumann et al.
A collaborative team consisting of researchers from four different universities has published a novel design rule for single-atom alloy catalysts to make the identification of promising catalysts more efficient. The rule can be used to eliminate the need for lengthy experimentation and extensive computer simulations.
The rule dubbed the "ten electron rule", provides new guidance for single atom alloy catalyst design. Single-atom alloys are a class of catalysts comprised of a few atoms of reactive metal, or dopant, that are diluted in an inert metal such as copper, silver, or gold. Published in Nature Chemistry, researchers from the University of Cambridge, University College London, the University of Oxford, and the Humboldt-University of Berlin, designed computer simulations to discover the underlying properties that control single-atom alloy catalysts.
A simple connection was observed, chemicals tended to bind the strongest to single-atom alloy catalysts when the dopant was surrounded by ten electrons.
"When you have a difficult chemical reaction, you need a catalyst with optimal properties,” said Dr. Romain Réocreux, a postdoctoral researcher who led the research. “On the one hand, a strong-binding catalyst may poison and stop accelerating your reaction; on the other hand, a weakly-binding catalyst may just do nothing."
"Now we can identify the optimal catalyst just by looking at a column on the periodic table. This is very powerful since the rule is simple and can speed up the discovery of new catalysts for particularly difficult chemical reactions."
Using the new design rule, the researchers presented a promising potential catalyst for an electrochemical version of a decades-old reaction called the Haber-Bosch process that relies on the same catalyst it has used since its discovery in 1909.
"Many catalysts used in the chemical industry today were discovered in the laboratory using trial and error methods,” added Dr. Julia Schumann. “With a better understanding of the materials' properties, we can propose new catalysts with improved energy efficiency and reduced CO2 emissions for industrial processes."