Introduction

Inherently conducting polymers (ICPs) such as polypyrroles, polythiophenes, and polyanilines (I-III shown in Scheme 1) are extremely useful organic electronic conductors. The applications of these materials have been reviewed recently [1-3], spanning areas as diverse as nanomaterials [4], elec-trochromics [5], sensors [6], artificial muscles [7, 8], smart membranes [9, 10], platforms for cell culturing [11, 12] and corrosion protection [13]. Many of these applications involve electrochemical switching processes (to be discussed in more detail). In the quest to improve electrochemical switching speeds of ICPs, researchers have recently turned attention to control of the structure at the nanodomain.

It is also interesting to note that ICP macrostructures are actually composed of nanodomains of much higher conductivity than the bulk material [14-17] suggesting that nano-dimensional control will also improve the bulk conductivity of ICPs.

The synthesis and electrochemical switching properties of ICPs such as polypyrroles (PPy), polythiophenes (PTh), and polyanilines (PAn) have been reviewed in recent monographs [18, 19].

The polymerization can be initiated chemically or electro-chemically and involves formation of lower molecular weight oligomers via oxidation. These are then further oxidized

(at lower potentials than the initial monomer) to form a polymer that eventually precipitates or deposits onto the anode in an electrochemical cell as a critical molecular weight is exceeded:

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