High temperature rearrangement of disordered nanoporous carbon at the interface with single wall carbon nanotubes

Production of Carbon Nanotubes from Polyethylene Pyrolysis Gas and Effect of Temperature

“…Furthermore, in Figure 10, it is seen how the 2D-band increased as well, and among all of them, the experiment at 700 °C is the one which contains the fewest disordered structures and the most parallel graphitic layers, although quite similar to the experiment at 750 °C. This indicates an important improvement of the crystalline degree with temperature, so the nanotubes with the best quality were, in agreement with TEM and XRD, those obtained at 750 °C, which is in accordance with the study of Yi et al 24 They deduced that higher temperatures reduced defects and increased the degree of graphitization after treating single-wall CNTs in a furnace at different temperatures.…”

Highly Graphitic Carbon Nanofibers Web as a Cathode Material for Lithium Oxygen Batteries

“…(Figure 1a,e,i) High magnification scanning electron microscope (SEM) images clearly reveal morphological changes in the surface as well as the junction between CNFs. (Figure 1b,f,j) The CNF 1200 and CNF 1400 have smooth surface while the CNF 1000 shows a rough surface, which indicates the rearrangement of carbon atoms by the increase of pyrolysis temperature [28,29]. The morphological change in the junction between CNFs is also significant.…”

Dramatic change of water-cluster accessibility of highly pure double-walled carbon nanotubes with high temperature annealing

“…19,20 It has been found that smaller diameter SWCNTs coalesce into larger diameter nanotubes with heat treatment at 1573 to 1773 K, [21][22][23] and form MWCNTs or graphitic nanoribbons at 1873 to 2273 K of HTT. 24,25 This situation is quite different from that of DWCNTs. With the benefit of their unique coaxial structure of double graphene layers, DWCNTs are of high thermal stability.…”

“…However, publications are devoted only to the investigation of the influence of HTT on the structural changes of CNTs with a focus on high-resolution transmission electron microscope (HRTEM) observations of the morphologies and microstructures. [21][22][23][24][25][26][27][28][29] There are few attempts to understand and evaluate the nanopore structural properties with gas adsorption. 7,30 Because HRTEM images and gas adsorption provide stochastic and statistical data, respectively, and because HRTEM observations and gas adsorption measurements present two-dimensional geometry and effective porosity (accessible to gas molecules), respectively, a systematic study with a gas adsorption technique has the potential to discover new aspects of the nanoporosity.…”