Probing graphene grain boundaries and enhancing the electrical properties of graphene films by Pt modification

Chloroplatinic acid (H2PtCl6·6H2O) was used to modify the grain boundaries of graphene films grown by chemical vapor deposition. Modification occurred only on the edge of the graphene layer in contact with Cu substrate. The grain boundaries of the continuous graphene films were directly observed after modification by optical microscopy and scanning electron microscopy. Energy-dispersive spectroscopy was also used to prove that only Pt nano-particles were modified on the grain boundaries. After chloroplatinic acid modification, the electrical properties of the graphene continuous films were optimized by Hall testing.