Conductive films of tetrathiafulvalene dicarboxylate cation radicals and poly(vinyl alcohol) formed by casting

Abstract Aqueous solutions of dipotassium tetrathiafulvalene dicarboxylate ( 1 ), potassium ferricyanide and poly(vinyl alcohol) were used to cast air-stable, flexible and electrically conductive films. Casting at 80–95 °C formed a network of microcrystals oriented in the film plane. Spectroscopic studies showed that these crystals contain π-stacks of the cation radical 1 + . No evidence for mixed valence stacks was found. A film containing 5 wt.% of 1 + in PVA had a four-point conductivity σ = 10 −2 S cm −1 in the film plane. The structural anisotropy led to a lower conductivity (10 −4 S cm −1 ) across the plane of the film.