Kengqing Jian

Visualization of liquid crystal director fields within carbon nanotube cavities

Multiwall carbon nanotube cavities were infiltrated with naphthalene polymer which exhibits a discotic nematic liquid crystal phase. The liquid crystal phase is covalently captured by thermal carbonization. High resolution transmission electron microscope images reveal a planar configuration consistent with elastic theory for extreme confinement conditions. Furthermore a spatial variation in order parameter was observed with a surface order parameter S0≈0.92 and an estimated correlation length ξ≈3.5nm.

Patterning lyotropic liquid crystals as precursors for carbon nanotube arrays

We report on a simple patterning technique using lyotropic liquid-crystal solutions to fabricate organized arrays of high aspect ratio carbon nanostructures. An automated pen writing system is used in conjunction with nanochannel alumina templates to produce ordered arrays of nanotubes and nanofibers in a variety of shapes, widths, and carbon crystal structures set by surface anchoring phenomena. The nanostructure arrays are characterized with optical and electron microscopy and Raman spectroscopy to establish the morphology and crystal structures of the carbon nanoform arrays.

Novel Carbon Nanotubes Based on Disk-Rod Assemblies of Lyotropic Liquid Crystals

ABSTRACT We have fabricated carbon nanofibers and nanotubes using disk-rod assemblies of lyotropic liquid crystals in which the orientation of graphene layers can be manipulated using surface anchoring techniques common to liquid crystal displays. The bulk material properties of the carbon can be engineered by the spatial arrangement of the graphene layers due to their anisotropic nature. We have also demonstrated a method to pattern arrays of nanotubes using an automated printing technique.

25.4: Micro‐Patterned Carbon Nanotube Arrays Using Pen‐Writable Lyotropic Liquid Crystals

We have fabricated carbon nanofibers and nanotubes using disk-rod assemblies of lyotropic liquid crystals in which the orientation of graphene layers can be manipulated using surface anchoring techniques common to liquid crystal displays. The bulk material properties of the graphene can be controlled by the spatial arrangement of the layers due to their anisotropic nature. We have also demonstrated a method to pattern arrays of nanotubes using an automated printing technique. Carbon nanotubes are being considered for a number of display applications.