Iron-Catalyzed Polymerization of Alkoxysulfonate-Functionalized 3,4-Ethylenedioxythiophene Gives Water-Soluble Poly(3,4-ethylenedioxythiophene) of High Conductivity

• Chemical polymerization of a 3,4-ethylenedioxythiophene derivative bearing a sulfonate group (EDOTS) is reported. The polymer, PEDOT-S, is fully water-soluble and has been produced by polymerizing EDOT-S in water, using Na2S2O8 and a catalytic amount of FeCl 3. Elemental analysis and XPS measurements indicate that PEDOT-S is a material with a substantial degree of self-doping, but also contains free sulfate ions as charge-balancing counterions of the oxidized polymer. Apart from selfdoping PEDOT-S, the side chains enable full water solubility of the material; DLS studies show an average cluster size of only 2 nm. Importantly, the solvation properties of the PEDOT-S are reflected in spin-coated films, which show a surface roughness of 1.2 nm and good conductivity (12 S/cm) in ambient conditions. The electro-optical properties of this material are shown with cyclic voltammetry and spectroelectrochemical experiment reveals an electrochromic contrast (̃48% at λmax ) 606 nm).

Subject headings

NATURVETENSKAP  -- Kemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences (hsv//eng)

Keyword

Ambient conditions

Catalytic amounts

Catalyzed polymerization

Chemical polymerization

Cluster sizes

Counterions

Electrochromic contrast

Electrooptical properties

Elemental analysis

Ethylenedioxythiophene

Functionalized

High conductivity

Self-doping

Side chains

Solvation properties

Spectroelectrochemical

Spin-coated films

Sulfate ion

Sulfonate groups

Water solubilities

XPS measurements

NATURAL SCIENCES

Publication and Content Type

ref (subject category)

art (subject category)