Interaction of platinum nanoparticles with graphitic carbon structures: A computational study

The interaction of platinum nanoparticles from a size of a few atoms up to 1 nm with extended carbon structures is studied by using quantum chemical methods. The aim is to obtain a deeper insight into the basic interactions between metal particles and carbon structures. For this purpose focus is placed on the type and strength of the interactions as well as the possibility to increase the adhesive forces by introducing chemical modifications (linker atoms) and defect sites or distortions of the support. The calculations show that there is a transition between an interaction with covalent character for smaller clusters and a dispersion-dominated interaction for larger particles. Furthermore, introduced linker atoms increase the covalent character of the interactions but also increase the distance between the cluster and the support, thereby leading to a lower interaction energy. This has implications for the design of chemical linkers or surface modifications to improve the durability of catalyst systems. Support groups: The interaction of platinum nanoparticles and graphene-like support structures (e.g. C96H24) is dominated by dispersion interaction (see picture). Covalent contributions to the interaction energy, Eint, are found only for clusters with fewer than 20 atoms. Defects in the support as well as the substitution of carbon by heteroatoms lead to an increased covalent contribution to the interaction. © 2013 WILEY-VCH Verlag GmbH amp; Co. KGaA, Weinheim