A collaborative effort spanning four universities has uncovered a straightforward guideline known as the “ten electron rule” for designing single-atom alloy catalysts tailored for specific chemical reactions. This rule simplifies the identification of promising catalysts, allowing scientists to propose compositions by merely consulting the periodic table, bypassing the need for extensive trial-and-error experiments or computationally demanding simulations.
Single-atom alloys, a catalyst category composed of two metals, involve a few atoms of a reactive metal (dopant) dispersed in an inert metal like copper, silver, or gold. Despite their efficiency in accelerating chemical reactions, traditional models fail to fully explain their mechanisms.
The research team, hailing from the University of Cambridge, University College London, the University of Oxford, and Humboldt-University of Berlin, published their findings in Nature Chemistry. Through computer simulations, they unraveled the governing principles behind the functionality of single-atom alloy catalysts.
The “ten electron rule” establishes a straightforward link: chemicals exhibit the strongest binding to single-atom alloy catalysts when the dopant is surrounded by ten electrons. This means that scientists can now streamline the catalyst selection process by examining periodic table columns to determine which catalysts possess the desired properties for their reactions.
Dr. Romain Réocreux, a postdoctoral researcher in Prof. Angelos Michaelides’ group, the leader of this research, notes, “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.”
Prof. Stamatakis from the University of Oxford, a contributor to the research, emphasizes the significance of this theoretical framework. He states, “After a decade of intense research on single-atom alloys, we now have an elegant, simple but powerful theoretical framework that explains binding energy trends and enables us to make predictions about catalytic activity.”
Leveraging this rule, the team proposed a promising catalyst for an electrochemical version of the Haber-Bosch process, a pivotal reaction for fertilizer synthesis relying on the same catalyst discovered in 1909.
Dr. Julia Schumann, who initiated the project at the University of Cambridge and is now at Humboldt-Universität of Berlin, highlights the potential impact, stating, “With a better understanding of the materials’ properties, we can propose new catalysts with improved energy efficiency and reduced CO2 emissions for industrial processes, moving away from the trial-and-error methods that often led to the discovery of catalysts in the chemical industry.”
Source: University of Cambridge