Structural anisotropy of magnetically aligned single wall carbon nanotube films

Thick films of aligned single wall carbon nanotubes and ropes have been produced by filtration/deposition from suspension in strong magnetic fields. We measured mosaic distributions of rope orientations in the film plane. for samples of different thicknesses. For an similar to 1 mu m film the full width at half maximum (FWHM) derived from electron diffraction is 25 degrees-28 degrees. The FWHM of a thicker film (similar to 7 mu m) measured by x-ray diffraction is slightly broader, 35 +/- 3 degrees. Aligned films are denser than ordinary filter-deposited ones, and much denser than as-grown material. Optimization of the process is expected to yield smaller FWHMs and higher densities, (C) 2000 American Institute of Physics. [S0003-6951(00)05131-7].