Graphite-like structure

All three have similar cubic structures (although boron nitride also has a graphite-like structure). 

The effect of oxidation pretreatment and oxidative reaction on the graphitic structure of all CNF or CNF based catalysts has been studied by XRD and HRTEM. From the diffraction patterns as shown in Fig. 2(a), it can be observed the subsequent treatment do not affect the integrity of graphite-like structure. TEM examination on the tested K(0.5)-Fe(5)/CNF catalysts as presented in Fig.2(b), also indicates that the graphitic structure of CNF is still intact. The XRD and TEM results are in agreement with TGA profiles of fi-esh and tested catalyst there is no obviously different stability in the carbon dioxide atmosphere (profiles are not shown). Moreover, TEM image as shown in Fig. 2(b) indicates that the iron oxide particle deposited on the surface of carbon nanofibcr are mostly less than less than 10 nm. 

Black phosphorus has a graphite-like structure and has a similar electrical conductivity. 

Carbon fiber is produced from several different organic polymers, but polyacrylonitrile has many advantages as a starting material. It is easily spun into fibers, and the chemistry of its pyrolysis reactions favors aromatization as a pathway to graphite-like structures. The process is outlined in reaction sequence (5). 

Structure Carbon subjected to +1300°C in helium atmosphere, resulting in a graphite-like structure in the form of polyhedra, with virtually no unsaturated bonds, ions, lone electron pairs, or free radicals Analytical Properties Especially for use in microbore columns suggested for lower aromatics but with some potential for higher-molecular-mass compound separations Reference 7-10... 

The carbon phase of obtained metal-carbon nanocomposites was shown to contain different types of nanostructured carbon particles in parallel with main graphite-like structures. Bamboo-like carbon nanotubes (CNT) with 14-30 nm in their outer diameter were observed in structured carbon material when GdCl3 was used as a component of composite-precursor (Fig. 4). In this case IR radiation intensity provides the heating of sample to 910 and 1000°C. 

Thus, the carbon phase of obtained metal-carbon nanocomposites represents in reality the carbon-carbon nanocomposite of main graphite-like structure with array of carbon nanostructures such as bamboo-like CNT, spherical or octahedral carbon nanoparticles. 

IR pyrolysis of PAN and PAN based composites yields ordered graphite-like structure as well as several carbon nanostructures, which were studied by means of Raman spectroscopy, XRD, including XRPA and TEM. The interlayer distance in graphite-like phase decreases and crystallite size grows with irradiation intensity... 

Stability of the graphite-like phase which appears in the irradiated diamonds as a result of polyamorphic transition with high decrease of density was studied using neutron and x-ray methods. The graphite-like structure was shown to be stable up to 50 kbar from ambient temperature to 1500 K at normal pressure. Simultaneously at rapid heating to 900-1000 K new (apparently metastable) modifications of carbon are formed. The diffraction patterns of the modifications do not coincide with those of known structures of carbon (diamond, lonsdeylite, graphite, chaoite, carbine, fullerene and its derivatives etc). It was shown that density of these structures does not differ much from the density of graphite, and at least one of these phases corresponds to a superstructure based on the bee modification of C8 with modified density [14],... 

Raman spectra were recorded using a Spex Triplemate spectrograph equipped with a diode array detector. The 514 nm line of an Ar+ laser was used for excitation. The Raman spectra displayed a band at approximately 1600 cm-1 due to C-C vibrations of graphite-like structures and a band at 1365 cm 1 due to imperfections of the graphite lattice and to amorphous carbon. The width of the 1600 cm"1 band in the Raman spectra has been reported to be inversely proportional to the degree of graphitization [5,6]. 

Other forms of carbon including charcoal, soot, lampblack, and coke are also known. Although these materials do not have structures that are highly regular, they are believed to have some local structure, and small units having graphite-like structures are known to exist. The fact that C6o was separated from soot shows that these useful and important forms of carbon are not completely without structure. 

It is remarkable that the series of peaks that appear after corona treatment is also observed in corona treatment of other polymers, e.g. polyester, polyethylene, and polystyrene. The nature of the low-molecular weight material thus seems to be independent of the type of polymer, suggesting a rather universal mechanism of formation. This mechanism is still unclear, but a pertinent observation may be that at very short treatment times the surfaces of many polymers indicate a high degree of unsaturation. This is seen in Table II, which shows the ratio 27/29, which is a measure of unsaturation. In corona as well as plasma treatments, the unsaturation increases steeply and then decreases with increasing time or dose. It is thus possible that many polymers initially form some sort of graphite-like structure which then reacts at a slower rate with oxygen. This would explain the similarity in the behavior of these polymers. 

These novel microstructures have extraordinary combination of physical and chemical properties [11-13], for this reason they become an important scheme of actually science work. One example of such nanomaterials is boron carbonitride (BNC) with graphite-like structure. Based on theoretical calculations, the existence of nanotube structures of BN was predicted in 1994, which was soon verified by the first synthesis of BN nanotubes in 1995. 

Properties. Boric acid is a white solid that crystallizes from aqueons solntions as triclinic waxy plates. The crystal structure of boric acid consists of planar sheets of planar trigonal B(OH)3 molecnles (1) linked by hydrogen bonds. This produces a graphite-like structure, accounting for the slippery feel of boric acid and the ease with which crystals cleave into flakes. This tribological property, or lubricity, has led to uses of boric acid as a lubricant. ... 

R. B. Kaner, J. Kouvetakis, G. E. Warble, M. L. Sattler and N. Bartlett, Boron-Garbon-Nitrogen Materials of Graphite-Like Structure, Mat. Res. Bull. 22 (1987) 399-404. 

Figure 12. Polymerization of acrylonitrile and pyrolysis to graphite-like structures.

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