Carbon black Particle surface crystallinity

A series of ZSM-5 zeolites synthesized using carbon black Black Pearls 2000 as secondary template was compared with ZSM-5 prepared by confined space synthesis and carbon-free ZSM-5. By secondary templating approach it is possible to prepare highly crystalline materials with mesopore diameter of 12 ran corresponding to the size of carbon black particles. Mesopore volume and mesopore surface area of obtained materials increase with increasing amount of carbon black in the reaction mixture. Observed decrease in micropore volume can be attributed to the increasing amount of Si04 tetrahedra on the mesopore surface. In the case of the sample prepared by eonfined space... 

Unlike diamond and graphite, which are crystalline carbons, carbon black is an amorphous carbon composed of fused particles called aggregates. Properties, such as surface area, structure, aggregate diameter and mass differentiate the various carbon black grades. 

Carbon Black is formed from the burning of gaseous or liquid hydrocarbons under conditions of restricted air access. According to electron micrographs taken with a phase contrast microscope, carbon black has a graphitelike microstructure with lattice distances of 0.35 nm. The layers lie parallel to the particle surface. Since discrete crystalline regions cannot be observed, the structure of carbon black is better described in terms of a paracrystalline state rather than a random distribution of graphite crystals. 

In the electrodes for PAFC, the Vulcan XC-72 carbon black is most widely used catalyst support material [95]. The oxidation of Vulcan carbon black in the presence of phosphoric acid at 191 °C showed that the disordered central part of carbon particles was oxidized while the outer crystalline part remained intact [96]. Among the attempts to improve the oxidation resistance of Vulcan carbon black, the most widely used method is the heat treatment which increases the level of graphitization on the carbon surface [97]. The heat treatment of Vulcan carbon black at the temperature of 2200 °C which reduced the surface area of Vulcan from 240 to 80 m /g improved oxidation resistance more than twofold [98, 99]. Other highly graphitic carbon materials such as CNT [100] and graphene [101] have been used as support materials because of their high surface area and electrical conductivity. When selecting the carbonsupport material, the oxidation resistance is the critical property for carbon supports to enhance the durability of HT-PEMFC MEAs however, the surface area, shape, and size of support material should also be considered to achieve the desired dispersion of Pt particles as well as the pore structure within the catalyst layer. 

Acetylene black is very pure with a carbon content of 99.7%. It has a surface area of about 65 m /g, an average particle diameter of 40 nm, and a very high but rather weak stmcture with a DBPA value of 250 mL/100 g. It is the most crystalline or graphitic of the commercial blacks. These unique features result in high electrical and thermal conductivity, low moisture absorption, and high Hquid absorption. 

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