Structure and Morphology of Carbon Materials

CARBON MATERIALS AS SUPPORTS FOR FUEL CELL ELECTROCATALYSTS 

The term active or activated carbon refers to carbon materials manufactured by high-temperature (773 to 1273 K) pyrolysis of various vegetative residues (i.e.. 

Activated carbons possess high BET surface areas (400 to 2500 m /g) and micropore volumes (up to 1.2 cm /g), which makes them particularly attractive adsorbents. They are also used as supports for heterogeneous catalysts and sometimes, electrocatalysts [20]. In a number of patents it was claimed that addition of either activated carbons or activated carbon-supported Pt to the CLs composed of carbon black-supported catalysts improves cell performance [21], 

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Finally, we addressed the complex problem of carbon corrosion, which is particularly relevant for PEMFC durability and thus commercialization of PEMFC technology. Carbon supports with an ordered crystalline structure, such as graphi-tized carbons, CNTs, and CNFs, as well as pyrolytic carbons of the Sibunit family hold out hope for the development of CLs with higher durability. More systematic studies are required to unveil the complex influence of the structure and morphology of carbon supports on the performance of the CLs and eventually, to develop a new generation of structurally ordered tailored materials for PEMFC applications with enhanced catalytic activities, low noble metal contents, and high dmabilities. 

Exceptionally fascinating work (exploring the oxidation of methanol for use within fuel cells) investigated the structure, composition and morphology of support materials, which were found to significantly affect the catalytic characteristics of Pt-based nanocatalysts [115]. Considering the effects of different carbon supports of graphene (produced via chemical reduction of GO), SWCNTs and Vulcan XC-72 carbon upon the electrocatalytic characteristics of the... 

Carbon black Finely divided carbon made by incomplete combustion or decomposition of natural gas or petroleum-based oils in different types of equipment. According to the process and raw material used, it can be furnace (e.g., HAF), thermal (e.g., MT), or channel carbon black (e.g., EPC), each having different characteristics, such as particle size, structure, and morphology. The addition of different types of carbon blacks to rubber compounds results in different processing behavior and vulcanizate properties. 

Single-walled carbon nanotubes are known to possess extraordinary strength.138 Mechanical properties of BN nanotubes would be worthy of exploration. Unlike carbon nanotubes, BN nanotubes are predicted to have stable insulating properties independent of their structure and morphology. Thus, BN tubes can be used as nano-insulating devices for encapsulating conducting materials like metallic wires. Filled BN nanotubes are expected to be useful in nanoscale electronic devices and for the preparation of nano-structured ceramics. 

With the help of similarities and differences between processing of conventional polymers and carbon-blackfilled compounds on one side and processing of ICP on the other side, the need for an integrated chemical, physical, and processing view on ICP is shown. In conclusion, the value of processing ICPs via dispersion into materials of well defined structure and morphology for basic research as well as its emerging industrial use, is pointed out. 

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