Helical carbon and graphite films prepared from helical poly(3,4-ethylenedioxythiophene) films synthesized by electrochemical polymerization in chiral nematic liquid crystals.

Helical carbon and graphite films from helical poly(3,4-ethylenedioxythiophene) (H-PEDOT) films synthesized through electrochemical polymerization in a chiral nematic liquid-crystal (N*-LC) field are prepared. The microscope investigations showed that the H-PEDOT film synthesized in the N*-LC has large domains of one-handed spiral morphology consisting of fibril bundles. The H-PEDOT films exhibited distinct Cotton effects in circular dichroism spectra. The highly twisted N*-LC with a helical pitch of smaller than 1 μm produced the H-PEDOT film with a highly ordered morphology. The spiral morphologies with left- and right-handed screws were observed for the carbon films prepared from the H-PEDOT films at 800 °C and were well correlated with the textures and helical pitches of the N*-LCs. The spiral morphologies of the precursors were also retained even in the graphite films prepared from the helical carbon films at 2600 °C.