Halbleiter-Komposite aus [(Me3Sn)3FexCo1-x(CN)6]-Aggregaten (0 < x ≤ 1) und Polypyrrol / Semiconducting Composites Involving [(Me3Sn)3FexCo1-x(CN)6]-Assemblies and Polypyrrole

Abstract

Pyrrole has been incorporated into the channel-like cavities of polymers of the type: [(Me3Sn)3FeIII xCoIII 1-x(CN)6] with 0 < x ≤ 1. The resulting black composites involving polypyrrole (Ppy) and Fe(II) display electrical conductivities σ between ca. 10-5 and 10-1 S · cm-1. Usually, composites prepared in the presence of small amounts of H2O exceed those in conductivity resulting under strictly anhydrous conditions owing to notably lower thermal activation energies (0.04 to 0.08 eV). An oxidative polymerization mechanism differing from that assumed for “classical” modes of Ppy generation is likely, since the N(pyrrole)/Fe(II) ratio turns always out to be ≥ 1. Exposure of a composite with x = 1 to an atmosphere of NH3 causes a decrease of σ from 1.5 · .10-1 to 2.7 · .10-6 S · cm-1; this NH3 uptake, and the concomitant change of σ, appear to be partially reversible. 1-Methylpyrrole, 2,5-dimethylpyrrole and aniline are oxidized by, and incorporated into, the organotin polymer, too, but the resulting σ-values do not exceed ∼10-9 S · cm-1.