Overcoming Site Heterogeneity In Search of Metal Nanocatalysts.

Site heterogeneity of metal nanocatalysts poses grand challenges for catalyst design from first principles. To accelerate catalyst discovery, it is of pivotal importance to develop an approach that efficiently maps catalytic activity of nanoparticles onto geometry-based descriptors while considering the geometric strain and metal ligand of an active site. We demonstrate that there exist linear correlations between orbitalwise coordination numbers CNα and free formation energies of oxygen species (e.g., *OH and *OOH) at Pt sites. Kinetic analysis along with herein developed structure-activity relationships accurately predicts the activity trend of pure Pt nanoparticles (∼1-7 nm) toward oxygen reduction. Application of the approach to a search of Pt nanoalloys leads to several Pt monolayer core-shell nanostructures with enhanced oxygen reduction activity and reduced cost. The approach presented here facilitates a transition from traditional single-crystal models to nanoparticles in theory-guided catalyst discovery.