Atomically dispersed Pd catalysts in graphyne nanopore: formation and reactivity

Area of Science:

• Catalysis
• Materials Science
• Computational Chemistry

Background:

• Forming single-atom noble metal catalysts on carbon materials is difficult due to weak metal-carbon interactions.
• Graphyne, a novel carbon allotrope, offers potential as a catalyst support.

Purpose of the Study:

• To investigate the stability and catalytic activity of atomically dispersed palladium (Pd) on graphyne.
• To explore the potential of graphyne as a support for single-atom catalysts.

Main Methods:

• Density Functional Theory (DFT) calculations were employed to study Pd-graphyne interactions and diffusion barriers.
• Ab initio molecular dynamics simulations were used to confirm CO adsorption effects.
• The CO oxidation reaction mechanism and energy barriers were calculated using DFT.

Main Results:

• Atomically dispersed Pd in graphyne nanopores is significantly more stable than Pd clusters.
• A high diffusion barrier for Pd on graphyne confirms kinetic stability.
• CO adsorption can lead to Pd pulling, but the catalyst regenerates after CO oxidation.
• CO oxidation on Pd@graphyne exhibits a 0.62 eV energy barrier via the Langmuir-Hinshelwood mechanism.

Conclusions:

• Graphyne is an excellent support material for creating stable, atomically dispersed single-metal catalysts.
• The unique electronic and structural properties of graphyne enhance catalyst stability and performance.
• This work paves the way for designing advanced catalysts with graphyne supports.