Fabrication of oriented carbon nanotube ultrathin film using the liquid/liquid interface

Carbon nanotube(CNT) has a great attention due to their unique electronic, optical, and mechanical properties for future device fabrication. For application of CNTs to real devices, it is necessary to fabricate CNTs to two dimensional to three dimensional assemblies. In this presentation, we report a fabrication of oriented CNT film by using the oil/water interface. To prepare CNT film at the oil/water interface, a CNT aqueous dispersion was placed to a vessel and then organic solvent(n-hexane) was added to the dispersion to create the oil/water interface. When proper amount of ethanol was added to the vessel, a CNT film was created at the oil/water interface. We discovered that the carbon nanotube synthesized by alumina template method form monolayer film at the oil/water interface. This film formed at the oil/water interface can be easily transferred onto solid substrate by the Langmuir-Blodgett(LB) method. The transferred CNT film was characterized by atomic force microscope(AFM). From the analysis of the height image, it was concluded that the film was a CNT "monolayer". Moreover, the orientation of the monolayer was controlled by applying ac field.