Graphite graphitic character/materials

Condensation Products. Under typical alcohol oxidation conditions with excess of alcohol, considerable quantities of carbonaceous material can be formed, having a strongly graphitic character. The kinetics of its accumulation can be described by equation (30), where /I is a constant and t the time of exposure... 

In addition to the pore size distribution and surface area, surface chemistry is one of the most important properties of carbon materials. The surface chemistry can be studied by spectroscopy methods such as X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectroscopy (SIMS). However, these techniques can only be applied to the external surface. In the case of micro- and mesoporous carbons (e.g., activated carbons and OMCs), the external surface represents only a small portion of the surface. The largest portion of the surface is located in the pores. How information on the graphitic character of the surface of OMC can be obtained from low-pressure nitrogen adsorption data is discussed in this chapter. 

Applicability of APD to determine the graphitic character of carbon materials... 

As early as 1980, even before the discovery of the fullerenes, that is, S. lijima reported on the preparation of multilayered, spherical particles of graphitic character. He conceived them to be an sp sp -hybrid material, and his results went largely unnoticed. The structures described then were first interpreted as carbon onions only after the determination of the fuUerenes structure and after D. Ugar-te s finding that particles of fullerene soot may be transformed into multilayered fullerenes by electron irradiation (Figure 4.1). 

A suitable strategy to minimize the carbon corrosion issue is to use carbon materials which have higher graphite contents and therefore fewer structural defects at which the oxidation initiates [81]. Heat-treatment of carbon blacks at elevated temperature is known to be able to impart the graphitic character to the carbon black [77, 82, 83]. As seen from Fig. 22.5, graphitization of the carbon blacks improved the stability and catalyst durability, though at the expense of a significant decrease in the specific surface area of the support material. The specific surface area loss was found to be primarily due to the elimination of pores less than... 

The product is a microcrystalline black powder with a graphitic character. The powder diffraction pattern has been reported by Beckmann et al. Grinding tends to introduce some stacking disorder into the material and broadens reflections associated with the hkl h + k jtQ) lines in the powder... 

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