Single-walled BN nanostructures.

نویسندگان

  • E Bengu
  • L D Marks
چکیده

We describe in situ synthesis and characterization of single-walled BN nanotubes terminated by fullerenelike structures using electron-cyclotron resonance nitrogen and electron beam boron sources onto polycrystalline tungsten substrates. Detailed comparisons of experimental high-resolution electron microscopy images and simulations based upon molecular models show a dominance of kinks and bends involving fourfold and eightfold ring structures as against fivefold or sevenfold which have been found with carbon. Analysis of the structures as a function of film thickness indicates that they are growing by addition of atoms to the exposed ends of single sheets, not at the substrate-nanostructure interface.

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عنوان ژورنال:
  • Physical review letters

دوره 86 11  شماره 

صفحات  -

تاریخ انتشار 2001