Novel synthesis and electropolymerization of metallo-conjugated thiophene derivatives

Metal-containing conducting polymers are a new and interesting class of materials that combine some of the redox properties of conducting polymers and some of those of the metal ions. In metal-containing conjugated polymers, there are several possible arrangements of metal group relative to the backbone. In this study, new conducting metallo-polymers were designed with the incorporation of valeric bimetallic carboxylic acid complex and 4-hydroxy benzoic acid based on η6-aryl-η5-cyclopentadienyliron and ferrocene-3-carboxylic acid to hydroxymethyl EDOT (thieno[3,4-b]-1,4-dioxin-2-methanol) and 2-(3-thienyl)ethanol. The resulting monomers were then polymerized electrochemically by having the conjugated system as a backbone and the metallic moiety pendant to the backbone. On the other hand, the monomers were chemically polymerized with Bisphenol-A to retain the metal moiety in the backbone of the polymer, affording the possibility of strong electronic interactions between the organic bridge and metal group in this arrangement. Spectroscopic, thermal, and electrochemical characterizations were performed to highlight the structural attributes of the polymers. Morphological characterization revealed that the electrochemically modified electrode surfaces have a very porous surface area.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► New thiophene derivatives containing bimetallic cationic iron moieties. ► Electropolymerization on carbon fibre micro electrode surfaces. ► Higher capacitive, conductivity properties of organoiron-PEDOT compared to PTh films. ► Globular micro- and nano-sized structural formations with electrical conductivity.