Increased Electrical Conductivity in Poly(3,4-ethylenedioxythiophene) upon Cross-Linking

✍ Scribed by James D. Mendez; Christoph Weder

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 623 KB
• Volume: 209
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.200800317

✦ Synopsis

Abstract

Cross‐linked poly(3,4‐ethylenedioxythiophene) (PEDOT) films were synthesized by the oxidative polymerization of 3,4‐ethylenedioxythiophene in the presence of five different conjugated and non‐conjugated cross‐linkers. The concentration and structure of the cross‐linker was systematically varied to explore the influence on the electrical conductivity. Optimized compositions displayed an electrical conductivity of up to ≈800 S · cm^−1^; this corresponds to a conductivity increase of up to 36% compared to linear PEDOT prepared under identical conditions. An increase in the conductivity was only observed for the conjugated cross‐linkers that were incorporated in low concentrations, typically at a level of less than 2 mol‐%. Attempts to incorporate higher concentrations of cross‐linker led to phase separation and crystallization of the cross‐linker and afforded materials in which a significant reduction of the electrical conductivity was observed. The optical properties of the polymer were only marginally affected upon cross‐linking, even at high cross‐linker concentrations.

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