Approaches to conducting polymer devices with nano-structure: Electrochemical construction of one-dimensional and two-dimensional porphyrin-oligothiophene co-polymers

Nano-fabrication of conducting materials is an important subject for the construction of molecular electronic devices. We have reported the construction of highly ordered conducting polymers with tailor-made ultrafine nano-structure [1,2]. In this paper, we report the construction of sequentially ordered one- or two-dimensional metalloporphyrin polymers connected by oligothiophene bridges. One-dimensional phosphorus(V)porphyrin polymers linked with the various length of oligothienyl molecular wire toward the axial direction of the porphyrin ring were synthesized by the electrochemical polymerization of symmetrical phosphorus(V)porphyrin triads with two oligothienyl axial groups. The conductivity of the polymers was strongly enhanced by the photoirradiation, indicating that the photoinduced carrier formation. Two-dimensional metalloporphyrin polymers containing oligothienyl bridges were also prepared by the electrochemical oxidation of meso-tetrakis(oligothienyl)porphyrin metal complexes and fabricated as layered organic diode.