CVD Growth of Boron Nitride Nanotubes

Abstract

Multiwalled BN nanotubes are grown from nickel boride catalyst particles by chemical vapor deposition at 1000−1100 °C using borazine, B3N3H6, as the precursor. This precursor is generated in situ from molten salt that forms from mixtures of (NH4)2SO4, NaBH4, and Co3O4 at 300−400 °C. The BN nanotubes have concentric-tube structures, are free of internal closures, have crystalline walls, and exhibit lengths of up to ∼5 μm. The nanotubes often possess bulbous, flag-like, or club-like tip closures. A root-growth mechanism is proposed for the catalyzed process.

Computational study of boron nitride nanotube synthesis: How catalyst morphology stabilizes the boron nitride bond

“…CVD methods for producing BN filaments and BNNTs have been utilized in several works. [35][36][37][38][39][40][41] Gleize et al 35 used diborane and ammonia or N 2 gases as the boron and nitrogen containing precursors. These were deposited on various boride surfaces ͑including Zr, Hf, Ti, V, Nb, and Ta borides͒ at a temperature of 1100°C.…”

“…Lourie et al 37 deposited borazine on cobalt, nickel, and nickel boride catalyst particles and concluded that the boride catalyst gave the best results. Huo et al 39,41 used for the nitrogen containing precursor a mixture of ammonia and nitrogen gas.…”

Insights into the capping and structure of MoS2 nanotubes as revealed by aberration-corrected STEM

“…These kind of morphologies suggests the presence of energetically unfavorable odd-membered rings (e.g., pentagons and heptagons) in addition to favorable even membered rings (e.g., squares). [10][11][12][13] A flat tip with right-angle corners is the most common morphology for hexagonal BN networks. The right angle termination results from the presence of four-membered rings (B 2 N 2 squares) at the tip, instead of five-membered rings.…”

Anisotropic Hexagonal Boron Nitride Nanomaterials: Synthesis and Applications

“…Multi-walled and single-walled-BNNTs were firstly prepared, respectively, in 1995 [9] and 1996 [15]. Figure 1 BNNTs have been synthesized by several methods: Arc-discharge method [9]; laser heating/ablation [16]; CNT-substitution reactions [17]; chemical vapor deposition (CVD) [18]; solid-gas reaction [19]; low-temperature autoclave [20]; pore-template [21]; and arcjet plasma [22].…”

“…They made borazine by an in-situ reaction of (NH 4 ) 2 SO 4 with NaBH 4 [18]. The produced nanotubes have large diameters and exhibit a bamboolike structure.…”