Synthesis of BN nanotubes in a laser heated DAC

BN nanotubes were found in laser heated cBN and hBN at nitrogen pressures up to 10.1 GPa in a diamond anvil cell. The BN nanotubes were recrystallized from the BN-melts in a super critical nitrogen fluid. Their shape, bonding nature and stoichiometry were examined by high resolution electron microscopy and electron energy loss spectroscopy. The BN nanotubes did not contain any additional inclusion. The nanotubes typically exhibit 3–8 shells and stoichiometry of B/N∼1.