Authors:M. Błachnio, P. Staszczuk, and G. Grodzicka
Modified carbon multiwall nanotubes were prepared via the oxidation process by means of 65% nitric acid or ferric nitrate
dissolved with 65% nitric acid. Using special thermogravimetry and sorptometry methods physicochemical properties of pure
and modified nanotube surfaces were investigated. A numerical and analytical procedure for the evaluation of total heterogeneous
properties on the basis of liquid thermodesorption from the sample surfaces under the quasi-equilibrium conditions are presented.
The calculations of the fractal dimensions of carbon nanotubes using the sorptometry and thermogravimetry data is presented.
Authors:Eudes Lorençon, Rodrigo G. Lacerda, Luiz O. Ladeira, Rodrigo R. Resende, André S. Ferlauto, Ulf Schuchardt, and Rochel M. Lago
Carbonnanotubes (CNTs) have been intensely investigated due to their unique chemical, mechanical, and electrical behavior. The inherent properties of CNTs make them versatile supports for metallic nanoparticles
, the multi-wall carbonnanotube (MWNT) and the single-wall carbonnanotube (SWNT). A SWNT is a graphene sheet rolled into a cylinder with typical diameter on the order of 1.4 nm. However, a MWNT consists of several concentric cylinders with diameters
Authors:Goio Etxebarria, Mikel Gomez-Uranga, and Jon Barrutia
have already been discovered, although they are constantly being improved, and require massive amounts of basic nanomaterials such as multiwalled carbonnanotubes (MWNCTs), which means carbonnanotube (CNTs) 1 production capacity must be increased
Authors:F. Xu, L. Sun, J. Zhang, Y. Qi, L. Yang, H. Ru, C. Wang, X. Meng, X. Lan, Q. Jiao, and F. Huang
Heat capacities of the carbon nanotubes (CNTs) with different sizes have been measured by modulated temperature differential
scanning calorimetry (MDSC) and reported for the first time. The results indicated the values of Cp increased with shortening length of CNTs when the diameters of CNTs were between 60 and 100 nm. However, the values of Cp of CNTs were not affected by their diameter when the lengths of CNTs were 1–2 um, or not affected by the length of CNTs when
their diameters were below 10 nm. The thermal stabilities of the CNTs have been studied by TG-DTG-DSC. The results of TG-DTG
showed that thermal stabilities of CNTs were enhanced with their diameters increase. With lengths increase, the thermal stabilities
of CNTs increased when their diameters were between 60 and 100 nm, but there is a slight decrease when their diameters were
less than 60 nm. The further DSC analyses showed both released heat and Tonset increased with the increase of CNTs diameters, which confirms the consistency of the results from both TG-DTG and DSC on
CNTs thermal stability.
The lattice specific heat in carbon nanotubes is evaluated within the microscopic model proposed by Mahan and Jeon, published
in the Physical Review B, in 2004. Phonons are considered for single wall carbon nanotubes in armchair configuration. As expected,
low temperature and high temperature regions show different behaviour of specific heat. Carbon nanotubes are also displaying
a very interesting lattice transport depending on the tube diameter, with high thermal conductivities for small diameters.
fracture toughness, is trying to be solved by adding carbonnanotubes (CNT). This is expected to improve the mechanical and thermal behaviour of the epoxy resins, increasing also their electrical conductivity [ 1 – 3 ]. However, in the last years, it was