Functionalized 3,4-ethylenedithiathiophenes (EDTTs) as building blocks for poly (3,4-ethylenedithiathiophene) (PEDTT) derivatives

Overcoming intra-molecular repulsions in PEDTT by sulphate counter-ion

We set out to demonstrate the development of a highly conductive polymer based on poly-(3,4-ethylenedithia thiophene) (PEDTT), PEDOTs structural analogue historically notorious for structural disorder and limited conductivities. The caveat therein was previously described to lie in intra-molecular repulsions. We demonstrate how a tremendous >2600-fold improvement in conductivity and metallic features, such as magnetoconductivity can be achieved. This is achieved through a careful choice of the counter-ion (sulphate) and the use of oxidative chemical vapour deposition (oCVD). It is shown that high structural order on the molecular level was established and the formation of crystallites tens of nanometres in size was achieved. We infer that the sulphate ions therein intercalate between the polymer chains, thus forming densely packed crystals of planar molecules with extended π-systems. Consequently, room-temperature conductivities of above 1000 S cm-1 are achieved, challenging those of conventional PEDOT:PSS. The material is in the critical regime of the metal-insulator transition.

Electrochemical sensing application of poly(acrylic acid modified EDOT-co-EDOT):PSS and its inorganic nanocomposite with high soaking stability, adhesion ability and flexibility

A novel and simple strategy to prevent swelling, disintegration, cracking and peeling-off of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) film in water was developed.