Tandem Site- and Size-Controlled Pd Nanoparticles for the Directed Hydrogenation of Furfural

The conversion of biomass to useful chemical products requires precise catalytic properties to achieve the required activity, selectivity, and durability. Here we show, through optimized colloidal synthesis, the tandem control of Pd size and site availability for the directed hydrogenation of the bioderived intermediate furfural. Adjusting the temperature of colloidal reduction dictates the size of Pd nanoparticles; in some instances ultrasmall clusters of <20 atoms are achieved. However, changing the solvent system affects the PVA-Pd interaction and relative proportion of available surface sites (corners, edges, planes), allowing us to control the selectivity to the valuable hydrogenation products furfuryl alcohol and tetrahydrofurfuryl alcohol. We demonstrate, through combined experimental and computational studies, that Pd nanoparticle planes are more prone to deactivation through the formation of Pd carbide, resulting in the reduced efficacy of furfural binding. This approach to nanoparticle optimization is an important strategy for producing long-lasting, high-performance catalysts for emerging sustainable technologies.