Abstract
We prepared Ni nanoparticles (NPs) on Si substrates and Pt NPs on Ni NPs, Pt-Ni core-shell NPs, with sputter deposition and anneal treatment. The influences on the morphology of NPs varied with parameters, sputter time and anneal temperature The morphology of Ni NPs and Ni-Pt NPs was observed by field emission scanning electron microscopy (FE-SEM). We predicted the morphology of Pt NPs on Ni NPs used by electric measurements. The experiments indicates that Ni-NPs size is smaller and shape is more spherical when sputter time is shorter and anneal temperature is higher, respectively. We considered that higher anneal temperature might prompt the surface diffusion and NPs growth of Ni atoms on the substrate, while larger NPs size may attribute longer sputter time, which means larger amounts of sputtered atoms of target material. By electric measurements, we predicted that the morphology of Pt-Ni NPs is core-shell structure. In the feature, we will need to observe Pt NPs on Ni NPs in detail used by transmission electron microscopy (TEM).
