(598f) Electronic and Electrochemical Characteristics of Pt Monolayer on Graphene and Its Electrochemical Properties

Epitaxially grown Pt thin film on a graphene template is found to have a few monolayer thickness with structural stability comparable to Pt(111) surface and promising electrochemical activity. The newly synthesized thin film shows a quadrilateral-polygon structure of Pt in monolayer on graphene surface. In this study, we present a computational research on the unique architecture of the graphene-templated epitaxial Pt monolayer. Recently proposed strongly constrained and appropriately normed (SCAN) density function study (DFT) is employed to investigate the characteristics of the system. Electrochemical activities of the system are evaluated in terms of the free energy variation in oxygen reduction reaction (ORR). In architectures, Pt exhibits registry with the C-C bridge sites along the armchair and zigzag directions forming strong covalent bonds. Here, the details of the atomistic/electronic structures and binding energies are discussed. Interestingly, the ORR can occur on both Pt and graphene surfaces. This would provide a good strategy to protect metallic catalyst and to tune electronic structure of catalyst.