CO-Induced Structural Flexibility in Cu and Au Nano-Catalysts

Journal article, 2026

Catalyst nanoparticles are dynamic, and their structures depend on the reaction conditions. Although average shapes can be observed experimentally, it is challenging to monitor transient structures and the mechanisms for structural changes during operating conditions. Herein, we use Density Functional Theory-based kinetic Monte Carlo simulations to study how CO affects adatom formation and clustering on Cu and Au surfaces and nanoparticles. Adatoms are created at undercoordinated sites and are stabilized by the formation of metal–CO complexes. Clusters of adatoms are formed on the (100) facets for both metals. The clusters are transient for Au, whereas they can be regarded as precursors for Cu nanoparticle reshaping. Bulk vacancies are present for Au, whereas vacancies are mainly located in the surface layer for Cu. The work demonstrates the structural flexibility of Au and Cu nanoparticles in the presence of an adsorbate, which has consequences for their catalytic properties.