Probing the diffusion of benzyl alcohol over LSPR-assisted synthesised PdAu nanoparticles within hierarchical catalysts

We have immobilised PdAu bimetallic nanoparticles (NPs) for the first time on hierarchical SAPO-5. Hierarchically-porous (HP) zeotype materials (possessing micro- and meso-pores) have been recently developed, offering improved access to intra-framework active sites, as in mesoporous materials, yet retaining the selectivity of the microporous (MP) bulk. PdAu bimetallic NPs supported on a HP-SAPO-5 framework display enhanced catalytic activities over their MP analogues. We predict that the large difference in the catalytic activities of HP and MP frameworks is due to the hindrance in the mobility of the substrate molecules which can be studied by QENS spectroscopy. The effect of mesopores on the diffusion will give us an insight into the catalytic pathway and interaction of substrate molecules with the support materials.