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Laser flash and self-heating 3 ω techniques were employed to determine the anisotropic thermal conductivity and thermal diffusivity of a highly oriented, free-standing multiwalled carbon nanotube (MWCNT) sheet and a yarn drawn from a sidewall of the MWCNT forest grown by chemical-vapor deposition. Normalized to ideal high density structure the thermal conductivity and the thermal diffusivity along the alignment are 50 ± 5 W/m K and 45 ± 5 mm 2 /s, respectively, and are mostly limited by dangling terminals of bundles, intrinsic defects of individual nanotubes and phonon scattering within the bundles, which form the supporting matrix of the MWCNT sheet. The high degree of tube–tube overlap substantially decreases the electrical and thermal interconnection resistance, which usually dominates in randomly deposited mat-like nanotube assemblies. The extremely high surface area of the MWCNT sheet leads to excessive radial heat radiation that does not allow transferring the heat energy along the MWCNT sheet by means of phonons to distances >2 mm. On the other hand, the high surface area and negligible heat capacitance make it a perfect material for bolometric sensing ( r = 38 V/W) and heat dissipation.

High surface area nanoporous carbon has been prepared by thermo-chemical etching of titanium carbide TiC in chlorine in the temperature range 200–1200 °C. Structural analysis showed that this carbide-derived carbon (CDC) was highly disordered at all synthesis temperatures. Higher temperature resulted in increasing ordering and formation of bent graphene sheets or thin graphitic ribbons. Soft X-ray absorption near-edge structure spectroscopy demonstrated that CDC consisted mostly of sp 2 bonded carbon. Small-angle X-ray scattering and argon sorption measurements showed that the uniform carbon-carbon distance in cubic TiC resulted in the formation of small pores with a narrow size distribution at low synthesis temperatures; synthesis temperatures above 800 °C resulted in larger pores. CDC produced at 600–800 °C show great potential for energy-related applications. Hydrogen sorption experiments at −195.8 °C and atmospheric pressure showed a maximum gravimetric capacity of ∼330 cm 3 /g (3.0 wt.%). Methane sorption at 25 °C demonstrated a maximum capacity above 46 cm 3 /g (45 vol/vol or 3.1 wt.%) at atmospheric pressure. When tested as electrodes for supercapacitors with an organic electrolyte, the hydrogen-treated CDC showed specific capacitance up to 130 F/g with no degradation after 10 000 cycles.

Co-evaporation of carbon, in the presence of helium with some other element as catalyst, yields interesting new molecules of the fullerene family which have tubular morphologies with a cross-section at the nanoscale but lengths at the macroscale. In particular, using Ni or Co based mixtures as catalyst with the electric arc technique, one obtains single wall carbon nanotubes in large quantities, with an average diameter of 1.4 nm and which assemble themselves in highly crystalline bundles containing a few tens of elements. These nanotubes have been observed, characterized and studied using high resolution microscopy techniques. X-ray and electron diffraction have been used to characterize the crystalline nature of individual bundles. The diameter dispersion has been studied in detail using Raman spectroscopy which shows impressively well-resolved structures of the observed modes. A majority of (10, 10) armchair tubes is observed, but some other configurations are also present with slightly different diameters.

Inter- and intra-layer disorder in a representative hard carbon derived from epoxy novolac resin at 1000°C have been investigated by comparing both the elastic structure factor S(Q) and radial distribution function obtained from pulsed neutron time-of-flight measurements with calculations from simple hypothetic systems with specific disorder characteristics. The spatial relationship between these building blocks, planar graphene fragments with length scale of 1 nm, is probed in terms of inter-layer alignment and intra-layer connectivity. Coupled with the density of dangling bonds obtained from ESR and residual hydrogen concentration, these simulations provide sufficient information to construct an overall model of the carbon structure. Of special interest is the physical origin of the ubiquitous broad (002)-like reflection frequently interpreted as that from layers with a uniform interlay spacing (d002) It is found to be directly related to the misalignment between layers with an average interlayer spacing as that in crystalline graphite (3.35 A).

We have measured the bulk modulus K for C61D2 up to 1 GPa in the temperature range 175–343 K. For face-centered cubic C61D2 above 290 K, we find an anomalously low value for K below about 0.15 GPa, ...

A simple calculation, based on the effective mass approximation and assuming a purely two-dimensional Fermi surface, is performed to estimate the dependence of a -axis conductivity σ a upon intercalant concentration X in the lamellar compounds of graphite. The predicted behavior σ a ~ X 1 2 is in approximate agreement with experiment only for the case of ICI, which is attributed to the unusually large layer spacing, hence weak interaction between layers, in this compound.