Porphyrin-fused graphene nanoribbons

Graphene nanoribbons (GNRs), nanometre-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 defned positions in 
the conjugated backbone, which would be valuable for tuning their optical, 
electronic and magnetic properties. Here we report the solution-phase 
synthesis of a porphyrin-fused graphene nanoribbon (PGNR). This PGNR 
has metalloporphyrins fused into a twisted ford-edged GNR backbone; it 
consists of long chains (>100 nm), with a narrow optical bandgap (~1.0 eV) 
and high local charge mobility (>400 cm2
 V–1 s–1 by terahertz spectroscopy). 
We use this PGNR to fabricate ambipolar feld-efect transistors with 
appealing switching behaviour, and single-electron transistors displaying 
multiple Coulomb diamonds. These results open an avenue to π-extended 
nanostructures with engineerable electrical and magnetic properties 
by transposing the coordination chemistry of porphyrins into graphene 
nanoribbons