High-resolution analytical electron microscopy of boron nitrides laser heated at high pressure

摘要: High-resolution transmission electron microscopy and energy loss spectroscopy have been carried out for cubic hexagonal boron nitrides (BN) laser heated in argon or nitrogen media at pressures of 5-11 GPa a diamond anvil cell. In particular, recrystallized products irradiation from fluid phase the form tiny flakes investigated. The observations revealed perfect crystallinity (either BN) traces melting bulk. Multishelled circular polygonal BN nanotubes, which did not contain any additional inclusions, were found after heating nitrogen. nanotubes typically exhibited 3-10 shells, characteristic inner dimension cross-section 2-6 nm stoichiometry B/N ~1. They to grown either matrix mixture amorphous + turbostratic BN, had recrystalized on specimens' surface phase.