Atomic Layer Deposition of Platinum on the Oxygen-Pretreated Graphene Surface

Abstract

The deposition of Pt nanoparticles on graphene surfaces using atomic layer deposition (ALD) has recently emerged as a promising approach to synthesize high-performance Pt catalysts. Understanding the atomistic mechanisms of this process is crucial for improving the material quality. In this work, we employed first-principles simulation methods based on density functional theory, combined with ab initio thermodynamics and advanced sampling techniques, to investigate the graphene surface structures that may be involved in Pt ALD experiments. We examined the different reaction mechanisms occurring in the first half of the ALD cycle on the most stable surface structure, starting from the physisorption of MeCpPtMe₃ molecules on the graphene surface. Our results reveal that a divacancy defect combined with a single oxygen atom is the lowest free-energy structure, making it highly likely to form under oxygen pretreatment conditions. Notably, we identified the peculiar role of the divacancy in this defect site, which significantly enhances the reaction rates during the dissociation of the MeCpPtMe₃ ligands.