UC Irvine

Graphene nanoribbons (GNRs) have been studied extensively because of their extraordinary electronic properties. Due to the unique relationship of bandgap and physical width, GNRs have become one of the most promising candidates for electronic devices. Current GNR synthesis methods usually incorporate unzipping of carbon nanotubes, which is difficult to control. Template growth synthesis is presented as a novel idea to create GNRs in a controllable manner without using harsh chemicals.

The objective of this project was to learn more about the mechanism and feasibility of template synthesis as a means to produce GNRs. In this project, metallic carbon nanotubes were used as template to synthesize GNRs. First, a thin film of nanotubes was deposited on desired substrates, and then they were subjected to plasma etching to convert into an amorphous structure. The samples were then annealed with and without a carbon source as an attempt to produce GNRs. Atomic force microscopy measurements showed that nanotube height decreased and width increased after annealing, which suggests that a planar structure may have formed, such as graphene. Furthermore, Raman spectroscopy showed that after annealing, there was a slight increase in the G’ peak with respect to the G peak as well as a slight right-shift of the G’ band, which both indicate the presence of graphene structure. Future work will be to perform electrical measurements and transmission electron microscopy to further verify the presence of GNRs.