Structure-driven tuning of O and CO adsorption on AuCu nanoparticles: A density functional theory study

Nanoparticles are fascinating nanoobjects that are actively studied and widely employed in various fields, such as heterogeneous catalysis and advanced electrode materials. Their local atomic structure and composition can significantly impact their properties. We employed the state-of-the-art first-principles calculations to investigate the effects of AuCu nanoparticle structure and composition on the electronic properties, charge distribution, and CO and O adsorption energies. Two types of nanoparticles were examined in this study; specifically core-shell nanoparticles (Cu@Au, Au@Cu) and bimetallic alloy particles (Au-Cu), all with an average diameter of 2 nm (321 atoms) and exhibiting fcc, icosahedral, and amorphous structures. The research comprehensively investigated the electronic and adsorption properties of the proposed nanoparticles with regard to their ability to adsorb CO and O, revealing the potential for finely tuning of their properties by modifying their atomic structure and composition. Adjusting the core-to-shell ratio allows one to precisely tune the O and CO adsorption energies on the nanoparticle surface, particularly in fcc nanoparticles. This results in a narrower range of adsorption energies, specifically for CO adsorption, which cannot be achieved in bimetallic alloys. Our study shows the significance of this approach for fine-tuning adsorption energies on a nanoparticle surface.