Precursor Geometry Determines the Growth Mechanism in Graphene Nanoribbons

Tutkimustuotos: Lehtiartikkeli

Tutkijat

  • Fabian Schulz
  • Peter H. Jacobse
  • Filippo Federici Canova

  • Joost van der Lit
  • David Z. Gao
  • Adrianus van den Hoogenband
  • Patrick Han
  • Robertus J. M. Klein Gebbink
  • Marc-Etienne Moret
  • Pekka M. Joensuu
  • Ingmar Swart
  • Peter Liljeroth

Organisaatiot

  • Utrecht University
  • University of London, Goldsmiths
  • Tohoku University

Kuvaus

On-surface synthesis with molecular precursors has emerged as the de facto route to atomically well-defined graphene nanoribbons (GNRs) with controlled zigzag and armchair edges. On Au(111) and Ag(111) surfaces, the prototypical precursor 10,10'-dibromo-9,9'-bianthryl (DBBA) polymerizes through an Ullmann reaction to form straight GNRs with armchair edges. However, on Cu(111), irrespective of the bianthryl precursor (dibromo-, dichloro-, or halogen-free bianthryl), the Ullmann route is inactive, and instead, identical chiral GNRs are formed. Using atomically resolved noncontact atomic force microscopy (nc-AFM), we studied the growth mechanism in detail. In contrast to the nonplanar BA-derived precursors, planar dibromoperylene (DBP) molecules do form armchair GNRs by Ullmann coupling on Cu(111), as they do on Au(111). These results highlight the role of the substrate, precursor shape, and molecule-molecule interactions as decisive factors in determining the reaction pathway. Our findings establish a new design paradigm for molecular precursors and opens a route to the realization of previously unattainable covalently bonded nanostructures.

Yksityiskohdat

AlkuperäiskieliEnglanti
Sivut2896-2904
Sivumäärä9
JulkaisuJournal of Physical Chemistry C
Vuosikerta121
Numero5
TilaJulkaistu - 9 helmikuuta 2017
OKM-julkaisutyyppiA1 Julkaistu artikkeli, soviteltu

ID: 13696378