Dehydrogenation of Propane to Propylene by a Pd/Cu Single-Atom Catalyst: Insight from First-Principles Calculations

The catalytic properties of the single-Pd-doped Cu-55 nanoparticle toward propane dehydrogenation have been systemically investigated by first-principles calculations, and the possible reaction mechanisms and effects of the single and multiple Pd doping on the catalytic activity have been discussed. Calculations reveal that the low-energy catalytic conversion of propane to propylene by the Pd/Cu single-atom catalyst comprises the initial crucial C-H bond breaking at either the methyl or methylene group, the facile diffusion of detached H atoms on the Cu surface, and the subsequent C-H bond dissociation activation of the adsorbed propyl species. The single-Pd-doped Cu-55 nanoparticle shows remarkable activity toward C-H bond activation, and the presence of relatively inactive Cu surface is beneficial for the coupling and desorption of detached H atoms and can reduce side reactions such as deep dehydrogenation and C-C bond breaking. The single-Pd-doped Cu-55 cluster bears good balance between the maximum use of the noble metal and the activity, and it may serve as a promising single-atom catalyst toward selective dehydrogenation of propane.