Boron nitride nanotube precursor formation during high-temperature synthesis: Kinetic and thermodynamic modelling

High-quality boron nitride nanotubes were synthesized by annealing porous precursor in flowing NH3gas at 1150°C. The porous precursor B18Ca2(MgO)9was produced by self-propagation high-temperature synthesis (SHS) method using Mg, B2O3, and CaB6as 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.

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Obtaining the Nanostructured Nitride Composition TiN-BN Powder by the Self-Propagating High-Temperature Synthesis from the Azide KBF4-NaN3-Na2TiF6 and "NH4BF4-NaN3-Na2TiF6 Systems

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.698.507 ◽

2014 ◽

Vol 698 ◽

pp. 507-512

Author(s):

Irina Kerson ◽

Ljudmila Shiganova

Keyword(s):

High Temperature ◽

Boron Nitride ◽

Sodium Azide ◽

Composite Powder ◽

The Self ◽

Nanosized Powder ◽

Temperature Synthesis ◽

High Temperature Synthesis ◽

Halide System ◽

One Step

This paper presents the results of a study on the preparation of nanostructured nitride composition TiN-BN in the boron halide - sodium azide - titanium halide system by the azide SHS technology. SHS-Az technology makes it possible to produce powders having the desired properties, only in one step, without blending separately prepared powders of titanium nitride and boron nitride, and to obtain the final product in the form of micro-and nanosized powder nitride compositions TiN-BN by using complex halides of titanium and boron. Thus, the composite powder TiN and BN obtained from the KBF4-NaN3-Na2TiF6» and «NH4BF4-NaN3-Na2TiF6 systems can be classified as a nanostructured powder (nanopowder).

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Gradient nanoporous structures based on silicon carbide and boron nitride in self-propagating high-temperature synthesis

Powder Metallurgy and Metal Ceramics ◽

10.1007/s11106-010-9259-8 ◽

2010 ◽

Vol 49 (7-8) ◽

pp. 465-467 ◽

Cited By ~ 2

Author(s):

V. I. Uvarov ◽

I. P. Borovinskaya ◽

V. V. Zakorzhevskii ◽

I. G. Malevannaya

Keyword(s):

Silicon Carbide ◽

High Temperature ◽

Boron Nitride ◽

Temperature Synthesis ◽

High Temperature Synthesis ◽

Nanoporous Structures

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High-Yield Synthesis of Bamboo-Like BN Nanotubes Using Self-Propagation High Temperature Synthesized Porous Precursor

Materials Science Forum ◽

10.4028/www.scientific.net/msf.694.59 ◽

2011 ◽

Vol 694 ◽

pp. 59-63

Author(s):

Lai Ping Zhang ◽

Ji Lin Wang ◽

Yun Le Gu ◽

Guo Wei Zhao ◽

Qiong Li Qian ◽

...

Keyword(s):

High Temperature ◽

Boron Nitride ◽

Synthesis Method ◽

Chemical Vapor ◽

Boron Nitride Nanotubes ◽

High Yield ◽

Synthesis Process ◽

Chemical Vapor Deposition Method ◽

Temperature Synthesis ◽

High Temperature Synthesis

High-yield and high-purity bamboo-like boron nitride nanotubes were synthesized via an effective chemical vapor deposition method by annealing porous precursor under ammonia atmosphere at 1150 °C. The porous precursor, prepared by self-propagation high temperature synthesis method, was the key to bulk synthesis process. The as-synthesized boron nitride nanotubes were characterized by SEM, TEM, HRTEM, XRD, Raman and FTIR spectroscopy. These nanotubes had a bamboo-like structure with uniform diameters about 90 nm and length of more than 10 μm. The associated growth model is proposed in this paper.

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