Catalyst Engineering for Growth of One-Dimensional Nanostructures

Abstract

The objective of this thesis was to catalyst engineer for growth of one-dimensional nanostructures. Large-area of precisely placed Au nanoparticles and Ni nanopyramid were synthesized with tunable size eeand distribution by a combined top-down (interference lithography) and bottom-up approach. Silicon nanowires (SiNWs) and Carbon nanofibers (CNFs) were then successfully synthesized respectively. By proper post-plasma treatment, Ni catalyst at top splits into two inside CNF and one of the two migrates down through CNF body which changes the inner microstructure configuration during the process. Based on the observation, a method to fabricate Carbon nanoneedle (CNNs) from CNFs was then discovered. The obtained CNNs array was used to systematically study field emission characteristics and an optimum condition occurred when the interfiber-distance-to-fiber-height-ratio was equal to one.