▎ 摘　　要

A systematic investigation of Pt particles on graphene nanoflakes (GNFs) functionalized with hydroxyl groups (f-GNF) is carried out using density functional theory (DFT). It is found that in general the adsorption of the Pt cluster on f-GNFs is less stable than that on pristine GNFs, in agreement with the experimental findings. However, at certain concentration of hydroxyl groups the adsorption of Pt cluster is stabilized, because at these electron densities hybridization between Pt 5d and C 2p orbitals are relatively more favored. We also study the size effects of GNF and Pt cluster, and find that the adsorption properties depend on their sizes. From this study we put forward that loading of the Pt catalyst on carbon support could be controlled by engineering the concentrations of organic functional groups in the carbon support or by engineering the size of the Pt catalyst itself. (C) 2014 Elsevier B.V. All rights reserved.