The degradation of carbon supported Pt catalyst used in polymer electrolyte membrane fuel cells is a significant durability problem affected by the agglomeration and detachment of Pt particles from carbon support. The bond between Pt and carbon must be significantly strengthened in order to prevent performance loss. In this work, first principles calculations were carried out in an attempt to understand the role that metallic adatoms play in the enhancement of the Pt/carbon interface adhesion. Metallic adatoms including all first row transition metals as well as Li, Al, Zr, Nb, and Au were inserted into a Pt(111)/graphene interface. The work of separation required to break the interface between Pt-adatom or carbon-adatom bond was then calculated for each configuration, revealing that the carbon-adatom bond was weaker than the Pt-adatom bond, making it easier to break the interface from the carbon-adatom bond side. While Sc, Ti, Zr, and Nb displayed strong binding to both Pt and graphene surfaces, at the Pt/graphene interface, the bond with graphene was weakened. The strength of the Pt-adatom bond was proportional to the amount of charge transferred from the adatom to the graphene. Co, Ni and V were the most promising metals for strengthening the Pt/graphene interface. These metals donated charges that were distributed evenly between carbon and Pt and formed strong covalent bonds with carbon and moderate bonding to Pt.
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