Zhanhui Zhang

Synthesis of boron nitride nanotubes by self-propagation high-temperature synthesis and annealing method

High-quality boron nitride nanotubes were synthesized by annealing porous precursor in flowing NH3 gas at 1150°C. The porous precursor B18Ca2(MgO)9 was produced by self-propagation high-temperature synthesis (SHS) method using Mg, B2O3, and CaB6 as the starting materials, which played an important role in synthesis of BN nanotubes in large quantities. Samples were characterized by SEM, TEM, EDX, HRTEM, X-ray powder diffraction (XRD), Raman, and Fourier transform infrared (FTIR) spectroscopy. The as-synthesized BN nanotubes have an average diameter of about 150 nm with a wall/diameter ratio of 2/3. Mean length of the BN nanotubes was more than 10 µm. The effects of temperature, time, and the possible mechanism of the growth of the BN nanotubes were also discussed.

An effective precursor for growth of bubble-chain boron nitride nanotubes

Large amounts of bubble-chain boron nitride nanotubes were synthesised by annealing an effective precursor. The porous precursor was produced by self-propagation high-temperature synthesis method using Mg, B2O3, amorphous B and Fe2O3 as the starting materials, which played an important role in synthesis of BN nanotubes in large quantities. Samples were characterised by SEM, TEM, HRTEM, X-ray powder diffraction and Raman and Fourier transform infrared spectroscopy. The as-synthesised BN nanotubes revealed periodical bubble-chain structures, having diameters of range 20–200 nm and an average length of more than 5 µm. The effects of temperature, time and the possible mechanism of the growth of the BN nanotubes were also discussed.