Nano-level wettings of platinum and palladium on single-walled carbon nanotubes

Pt and Pd evaporation experiments were performed on single-walled carbon nanotubes (CNTs) to explore the Pt and Pd wetting characteristics on the surface of a CNT via ultrahigh vacuum scanning tunneling microscopy (UHV-STM) at low temperature. Differences in the size were noted between Pt and Pd nano-clusters as the coverage increased. Pt clusters were formed discretely on the groove sites in double-stranded CNTs. On the other hand, Pd clusters were coated uniformly on the CNTs due to the size of the cluster, which was very small. Hence, Pd is verified to be feasible for wetting on CNTs. It can provide low contact resistance in transport measurements.