Graphene nanoribbons show semiconducting behavior that renders them suitable active materials for electronic devices. A team led by Klaus Müllen, Max Planck Institute in Polymer Research, Germany, has described the bottom-up synthesis of shape-controlled graphene nanoribbons.

Polymeric polyphenylene precursors were prepared by using microwave-assisted Suzuki-polycondensation, and were then converted into the corresponding graphene nanoribbons by a multiple Scholl reaction using FeCl₃ (see reaction scheme in figure). The structure of these nanoribbons was confirmed by NMR spectroscopy and MALDI-TOF mass spectrometry, while other precursors showed a red shift of the emission maximum in the UV/Vis and photoluminescence spectroscopy.

Images: (c) Wiley-VCH

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