Polyacrylonitrile carbonized

Another interesting type of novel carbons applicable for supercapacitors, consists of a carbon/carbon composite using nanotubes as a perfect backbone for carbonized polyacrylonitrile. Multiwalled carbon nanotubes (MWNTs), due to their entanglement form an interconnected network of open mesopores, which makes them optimal for assuring good mechanical properties of the electrodes while allowing an easy diffusion of ions. 

In practical application, it was reported that the platinum particles dispersed in highly porous carbonized polyacrylonitrile (PAN) microcellular foam used as fuel-cell electrocatalyst160 have the partially active property. The fractal dimension of the platinum particles was determined to be smaller than 2.0 by using the potentiostatic current transient technique in oxygen-saturated solutions, and it was considered to be a reaction dimension, indicating that not all of the platinum particle surface sites are accessible to the incoming oxygen molecules. 

The details of so-called Black Orion production have been given in many papers. Also, the properties of carbonized polyacrylonitrile are well known because of which it is in demand especially as a component of composites, mainly because of its strength and high thermal resistance. 

Polyaniline has been formed in the pores of Cu- or Fe-exchanged MCM-41 by adsorption of aniline vapour and subsequent oxidative polymerization (Figure 7.23), and these molecular wires demonstrate significant electronic conduction, although less than that of bulk polyaniline. Pyrolysis of polyacrylonitrile in the pores produces a graphitelike carbon chain, which exhibits microwave conductivity ten times that of bulk carbonized polyacrylonitrile. Such materials have potential for use in information processing as storage capacitors. 

Ye S, Vijh AK, Dao LH (1996) A new fuel cell electrocatalyst based on highly porous carbonized polyacrylonitrile foam with very low platinum loading. J Electrochem Soc 143 (1) L7-L9... 

Carbon fibers were used about 100 years ago by Edison for his electric lamps. In 1964, the carbonized polyacrylonitrile (Orion) fibers were first produced with a tensile strength of about 2,000 MN/m and a high modulus of over 400,000 MN/m. Thus, carbon fiber-reinforced resins are very stiff and have found wide application in artificial limbs, golf clubs, tennis rackets, skis, and many aircraft parts. However, the composites are not especially strong in tension. 

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