Core-Shell Structured Supported Size-Selective Catalysts with High Catalytic Activity

Heterogeneous catalysts are widely used due to many advantages including the easiness of separating the catalysts by filtration after reaction. However, heterogeneous catalysts cannot selectively convert specific molecules in the reactant mixture to only desired products. Size-selective catalysis is an important concept of improving the selectivity of heterogeneous catalysts. In previous studies, both supported and unsupported metallic nanoparticles were enshrouded in relative thick porous structures to realize the size-selectivity of heterogeneous catalysts. However, the catalytic activity of the catalysts reduced significantly due to the mass transfer limitation brought by the relatively thick shells. In this study, we deposited an ultra-thin porous oxide shell on supported Pt catalysts using molecular layer deposition (MLD) method. The core-shell catalyst shows pretty high catalytic activity and size-selectivity in hydrogenation reactions of n-hexene over cis-cyclooctene.