Exploring Hydrophobicity in Halogen-Substituted EDOT Films

Three new monomers of 3,4-ethylenedioxythiophene (EDOT) were synthesized and tested for electropolymerization feasibility. The organic moiety attached to the EDOT unit contained a fluorinated, chlorinated, or unsubstituted phenol ring  The monomers were electropolymerized onto both glassy carbon and ITO surfaces. The polymer coatings were characterized in supporting electrolyte solutions of dichloromethane and water using cyclic voltammetry.  Other methods such as atomic force microscopy (AFM), ellipsometry, and contact angle measurements were also used to characterize the polymer coatings.  Cyclic voltammetric studies and contact angle measurements indicate that the fluorinated compound produces a hydrophobic film, while the film from the phenolated compound showed less hydrophobicity. From initial results, the chlorinated compound appears to be more similar to the fluorinated monomer than the phenolated compound.