LAUSR

Abstract Nanoparticles composed of palladium and platinum are particularly interesting for catalytic purposes, for instance, selective hydrogenation and alcohol oxidation. The reactivity and selectivity of nanostructures are mostly based on the size and shape of the nanocrystals in catalytic reactions. In this work, we studied the structural stabilities of Pd and Pt based nanocubes and nanocages and adsorption strength of chemisorbed species on these nanostructures to investigate their structure dependent catalytic activities. Solid cubic and hollow cage like nanostructures of different sizes were designed with Pd and Pt atoms. The volume of the crystal cavity in nanocage structures was tuned by removing of atoms from solid cubic structure. The effect of size and shape on the formation energies and HOMO-LUMO energy gap of nanostructures were elucidated and correlated to structural stabilities, hardness-softness, electronegativity and electrophilicity index. The relationship between size and chemical reactivity clearly showed that increasing the number of atoms participating in a catalyst enhances the activity. For further understanding of the catalytic activity we employed 4-nitro thiophenol, as an S-donor representative molecule, to evaluate the adsorption characteristics of the nanostructures.