Porphyrin-Fused Graphene Nanoribbons

Graphene nanoribbons (GNRs), nanometer-wide strips of graphene, are promising materials for fabricating electronic devices. Many GNRs have been reported, yet no scalable strategies are known for synthesizing GNRs with metal atoms and heteroaromatic units at precisely defined positions in the conjugated backbone, which would be valuable for tuning their optical, electronic and magnetic properties. Here, we report the first solution-phase synthesis of a porphyrin-fused graphene nanoribbon (PGNR). This PGNR has metalloporphyrins fused into a twisted fjord-edged GNR backbone; it consists of long chains (>100 nm), with a narrow optical bandgap (~1.0 eV) and extraordinarily high local charge mobility (>400 cm2 V–1 s–1 by Terahertz spectroscopy). It has been used to fabricate ambipolar field-effect transistors with appealing switching behavior, and single-electron transistors displaying multiple Coulomb diamonds. These results open an avenue to PGNRs with engineerable electrical and magnetic properties, transposing the coordination chemistry of porphyrins into π-extended nanostructures.