Light-Driven Dehydrogenation of Propane Using Plasmonic Al@TiO2 Core–Shell Nanoparticles with Pt Single Atoms and Clusters

Abstract

Non-oxidative dehydrogenation of propane produces valuable propylene feedstocks and clean hydrogen fuel but, as an endothermic reaction, conventionally requires high temperatures. Here we report a photocatalyst that combines plasmonic Al@TiO₂ core–shell nanoparticles with Pt single atomic active sites and clusters, capable of efficient dehydrogenation of propane into propylene with high selectivity using visible light illumination. Through strong metal–support interactions, the reducible TiO₂ shell layer controls the nuclearity of the exposed Pt species, which in turn controls their photocatalytic reactivity. A comparison of reaction orders for the light-driven and the corresponding thermally driven process shows that hot carriers lower the apparent C−H activation energy barrier. Plasmon-generated hot carriers, along with the presence of low-coordination Pt sites, suppress further dehydrogenation of propylene and prevent coke formation that would otherwise occur on extended Pt islands. This work clearly demonstrates how plasmonics and single atom catalysts can be combined for high-specificity photocatalyst design.