Catalyst-free synthesis of boron nitride single-wall nanotubes with a preferred zig-zag configuration - art. no. 121405

Boron nitride nanotubes (BNNTs) were synthesized in gram quantities using a continuous CO; laser ablation reactor without the benefit of a metal catal yst. High-resolution transmission electron microscopy analyses have shown t he samples to be composed of single-wall nanotubes organized in long and we ll-crystallized bundles containing about ten tubes. The samples also contai n a small amount of double-wall BNNTs and multiwall boron nitride fullerene like "cages." The majority of the BNNTs were identified as having the zig-z ag configuration, as attested by the 0.2 nm period array of spots observed along tube walls; the other tubes are either armchair or chiral. The BNNTs seem to be attached at one end to nanoparticles which were shown in electro n spectroscopy imaging mode to be composed of pure boron, thus supporting a root-based growth mechanism.