Deposition Methods for PEDOT Cathode

Ideally the polymer would fill the open pore structure of the porous anode material, which is covered with the dielectric. However, typically only a few 

SEM pictures of the porous structure of a tantalum anode coated with a PEDOT cathode film at low (left) and high resolution (right). 

Porous Ta/Nb anode with polymer cathode Epoxy encapsulant 

The formation of a conductive polymer cathode in electrolytic capacitors is hindered by the porous structure of the anode, especially for modern materials with very fine pores. In situ polymerization or the deposition of conducting polymer dispersions have to be applied for the formation of the polymer cathode since high performance conducting polymers are not soluble. 

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