Formation of bamboo-shape carbon nanotubes by controlled rapid decomposition of picric acid

Abstract

In the presence of catalysts, carbon nanotubes (CNTs) can efficiently grow in the environment generated by the rapid decomposition of normal explosives. Controlling the reaction parameters of a mixture of picric acid (PA) with cobalt acetate and paraffin can lead to a welldefined morphology of CNTs. The formation of bamboo-shape tubes is favorable at relatively high Co(AC) 2 /PA and paraffin/PA ratios. It is found that the bamboo-shape tubes are different in morphology and structure and can be categorized roughly into two types, according to the participation of the catalyst nanoparticles. The formation of the two types is discussed.

Fe catalysts for methane decomposition to produce hydrogen and carbon nano materials

“…When increasing the reaction SV, i.e., accelerating the graphite precipitation rate, a new type of bamboo-shape CNTs with Fe3C trapped into the cavity is formed by the mechanism illustrated in Figure 12(g). ''Jumps'' of the catalyst particles out of the graphite sheath to the top of the tube at regular time intervals was inferred by Y. Lu et al [78] to explain the formation of bamboo-shaped CNTs with catalyst particle at tube end. The motive force of pushing out the catalyst particle may be a stress accumulated in the graphitic sheath due to the segregation of carbon from the inside of the sheath.…”

Bamboo-shaped carbon nanotubes generated by methane thermal decomposition using Ni nanoparticles synthesized in water–oil emulsions

“…However, another possibility suggested through this result is that when bamboo-shaped carbon structures are growing catalytically, the metal particles are located preferentially in the widest side of the carbon compartment, and in many of these holes the widest sides can be as large that the carbon walls of the tube began to become thinner leading to the detachment of metal particles during the CNTs growth. For example, in the different morphologies when these nanostructures were synthesized by different catalytic methods (Li et al, 1999;Zhang et al, 2001;Chen et al, 2001;Lu et al, 2004). Zhang et al (2001), using a Ni/metallic oxide catalyst, produced V-shaped hollow core CNTs with outside diameters in the 20-60 nm range.…”

Shock-wave synthesis of multilayer graphene and nitrogen-doped graphene materials from carbonate

“…In the presence of catalysts, carbon nanotubes (CNTs) can efficiently grow in the environment generated by the rapid decomposition of normal explosives. Controlling the reaction parameters of a mixture of picric acid (PA) with cobalt acetate and paraffin can lead to a well-defined morphology of CNTs [24]. In this study, we present a new approach to synthesize graphene materials and NG using the shock-wave method.…”