Greatly enhanced adsorption and catalytic activity of Au and Pt clusters on defective graphene.

Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore.
The Journal of Chemical Physics (Impact Factor: 3.16). 05/2010; 132(19):194704. DOI:10.1063/1.3427246
Source: PubMed

ABSTRACT We report an investigation on CO oxidation catalyzed by Au(8) or Pt(4) clusters on defective graphene using first-principles approach based on density functional theory. The simplest single-carbon-vacancy defect on graphene was found to play an essential role in the catalyzed chemical reaction of CO oxidation. When supported on a defect-free graphene sheet, the reaction barrier of CO oxidation catalyzed by Au(8) (Pt(4)) clusters was estimated to be around 3.0 eV (0.5 eV), and when adsorbed on defective graphene, the reaction barrier was greatly reduced to around 0.2 eV (0.13 eV).

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Miao Zhou