Catalytic growth of boron nitride nanotubes

Boron nitride (BN) nanotubes were synthesized by heating a mixture of boron and alumina-supported nickel boride catalyst at the temperatures from 1100 to 1300 °C under nitrogen or ammonia atmosphere. The BN Nanotubes exhibit a well-crystallized tube structure with 5–40 nm in diameter and several microns in length. Their tip morphology and chirality depend on the diameter of BN nanotubes. Bamboo- and polar-like BN could be obtained when the synthesized temperature increases to 1400 and 1500 °C, respectively. The catalytic growth mechanism was also proposed to explain the growth of BN nanotubes.