Synthesis and characterization of one-dimensional nanomaterials (nickel nanowires) using chemical vapor deposition method

Abstract

One-dimensional nanowires, i.e., nickel nanowires (NW) were synthesized on amorphous SiO2/Si substrates and nickel foams by chemical vapor deposition (CVD) method, using argon as the carrier gas and nickel chloride as the precursor. Morphologies of the Ni NWs were characterized using optical microscope (OM) and scanning electron microscope (SEM). The work of this project contains the following parts: 1) Investigation of the CVD synthesis conditions, such as growth temperature, time, and flow rate of argon gas. The results show that the diameter and length of as-grown Ni NWs are affected by two of the CVD parameters, i.e., the growth temperature and the flow rate of argon carrier gas while, growth time was found to be independent of the diameter and length of nickel NWs. 2) Influences of substrates on the morphologies of Ni NWs were also studied. It is found annealing treatments on the surfaces of SiO2/Si substrates did not favor the nucleation and growth of nanowires, while, piranha cleaning of SiO2/Si substrates has found to decrease the impurities on substrates thus favoring nucleation and growth of nanowires. 3) Position-controllable growth of Ni NWs was achieved. Ni NWs were successfully grown along tweezer scratched patterns on the SiO2/Si substrates.

The substrate for growth of Ni NWs was further extended to three-dimensional substrate by our synthesis method, such as Ni foam and 3D graphene networks. Graphene/Ni foam substrates were found to be favorable substrate surfaces for the growth of nickel nanowires. With one-dimensional nanowires grown on graphene/Ni foam substrates, three-dimensional nanostructures were produced.