A Single Atom's Journey Defines a Nanocatalyst's Power

Defects in nanomaterials are not always flaws; they can be powerful features for driving chemical reactions. Yet, understanding how they work at the atomic level has been a persistent challenge. Now, researchers have investigated two distinct copper nanoclusters, tiny, precisely structured groups of atoms known as Cu20S and Cu13H10.

Both possess a similar surface vacancy, or defect, but their behaviour couldn't be more different. Only the Cu13H10 cluster showed remarkable efficiency as a catalyst for a reaction called semi-hydrogenation.

Using theoretical modelling and NMR studies, the team discovered the atomic-level secret. In the high-performing Cu13H10, a central hydride atom migrates to the surface defect, activating it as the catalytic site. In the sluggish Cu20S, a copper atom makes a similar journey, but this creates an inefficient defect. This work paves the way for the rational design of new nanomaterials by controlling their atomic-level organisation.