Structure determinations of double-wall carbon nanotubes grown by catalytic chemical vapor deposition
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We report an application of nanoarea electron diffraction for structure determination of double-wall carbon nanotubes (DWNT) grown by catalytic chemical vapor deposition. The structures of 30 tubes were determined from experimental diffraction patterns. Among these tubes, the inner and outer wall structure of 18 tubes was precisely determined by comparison with kinematic electron diffraction simulations. For the structure of the DWNTs, our experiment revealed a mixture of semiconducting-metallic (S-M), S-S and M-M tubes. The spacing between the two walls ranges from 0.335 nm to 0.384 nm. Most DWNTs are incommensurate and chiral.
KeywordsGraphene Sheet Outer Wall Outer Tube Chiral Angle Wall Spacing
Work on electron microscopy characterization is supported by DOE DEFG02-01ER45923 and DEFG02-91ER45439 and uses the TEM facility of Center for Microanalysis of Materials at FS-MRL. M.G. thanks Dr. M. Kociak for discussions.
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