Carbon electro catalytic properties

It should be mentioned that the structure of carbon supports could have significant influence on the electro-catalytic properties of the nanocomposite catalysts. Recently, Pt/Ru nanoclusters prepared by the alkaline EG method were impregnated into a synthesized carbon support with highly ordered mesoporous. Although the Pt/ Ru nanoclusters can be well dispersed in the pores of this carbon substrate, the long and narrow channels in this material seem not suitable for the application in... 

Electro)catalytic properties Undoubtedly, the most frequently emphasized feature of CNT- and IL-based carbon pastes is their (self)catalytic character... 

Although increased sensitivity and reproducibility has also been reported for pulsed potential cleaning at carbon electrodes by several researchers [60, 61], these electrodes have not generally been successful for the detection of polar aliphatic compounds. This effect is attributable to the absence of appropriate electro-catalytic properties of carbon surfaces to support the anodic oxygen-transfer reaction mechanisms of polar aliphatic compounds. 

The finely dispersed Pt with particle sizes ranging from 2-5 nm supported over mesoporous carbon materials showed excellent electro-catalytic properties. Further, the activities were much higher than that obtained with Pt-supported activated carbon (PttAC), commercial Pt-supported Vulcan (XC-72) carbon, Pt/E-TEK catalysts. 

Carbon composites result from the combination of carbon with one or more dissimilar materials. Each individual component maintains its original characteristics while giving the composite distinctive chemical, mechanical and physical properties. The capability of integrating various materials is one of their main advantages. Some components incorporated within the composite result in enhanced sensitivity and selectivity. The best composite compounds will give the resulting material improved chemical, physical and mechanical properties. As such, it is possible to choose between different binders and polymeric matrices in order to obtain a better signal-to-noise ratio, a lower nonspecific adsorption, and improved electrochemical properties (electron transfer rate and electro catalytic behavior). 

A further observable nuance in behavior of these mixtures in comparison with traditional pastes is lowered irreversibility for some redox systems, which is in direct relation with the most distinctive property of all new carbon pastes - their (electro)catalytic capabilities (see below). Finally, in the CIL(E) arrangement, yet another benefit is enhanced chemical activity toward some ion-exchange and ion-pairing reactions [59, 72, 73]. 

Electrochemical energy conversion for technical applications relies on a high catalytic reactivity. The electro catalytic reactivity is strongly influenced by the structure and composition of the surface of the catalysts. In PEMFC the catalysts consist of Pt or Pt alloys, which are of nanometer size and often supported on carbon in order to optimize the surface area and the costs of the noble metals. However, the important relation between the reactivity and the structure is obscured in technical electro catalysts by a variety of parameters, like, e.g. the properties of the carbon support, the preconditioning of the catalyst, and the structure of the interface between the electrolyte and the active layer (e.g. the Nafion content). An excellent review on the PEM fuel cell electrodes is given by Litster and McLean (2004)... 

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