Manipulation of the geometric and electronic parameters of metal nanocatalysts

Metal nanoparticles find wide use in the field of catalysis owing to their high surface to volume ratio. The catalytic activity depends on the interaction between the molecular substrate and catalyst surface. This substrate-catalyst interaction can be regulated by manipulating the geometric and electronic parameters of these nanoparticles. The shape and size of the nanoparticles dictate the geometric parameters whereas their composition controls the electronics of these catalysts. Manipulation of these parameters can be used to tune catalytic activities; hence, a better understanding of their regulation will help in designing efficient catalysts.;The synthesis and characterization of a series of monometallic Pd and core shell Au Pd nanoparticles with varying shapes and sizes will be discussed in this presentation. These nanocrystals were used to catalyze two model reactions: selective hydrogenation of 2-hexyne and oxidation of formic acid. Comparison of their catalytic activities by varying one parameter at a time (either size or shape) helps to identify the effect of geometric parameters on catalysis. Additionally, comparison of particles with varying composition but same geometric features provides insight into how the electronics underlying the catalysis can be manipulated through nanostructure architecture. We find that a balance in binding interaction between the substrate and catalyst surface is necessary to design an efficient catalyst and can be achieved with shape-controlled core shell nanocrystals.