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arXiv · 1704.06373

Electronic Structure Evolution during the Growth of Graphene Nanoribbons on Au(110)

Ada Della Pia·Giulia Avvisati·Oualid Ourdjini·Claudia Cardoso·Daniele Varsano·Deborah Prezzi·Andrea Ferretti·Carlo Mariani·Maria Grazia Betti
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Abstract

Surface-assisted polymerization of molecular monomers into extended chains can be used as the seed of graphene nanoribbon (GNR) formation, resulting from a subsequent cyclo-dehydrogenation process. By means of valence-band photoemission and ab-initio density-functional theory (DFT) calculations, we investigate the evolution of molecular states from monomer 10,10'-dibromo-9,9'bianthracene (DBBA) precursors to polyanthryl polymers, and eventually to GNRs, as driven by the Au(110) surface. The molecular orbitals and the energy level alignment at the metal-organic interface are studied in depth for the DBBA precursors deposited at room temperature. On this basis, we can identify a spectral fingerprint of C-Au interaction in both DBBA single-layer and polymerized chains obtained upon heating. Furthermore, DFT calculations help us evidencing that GNRs interact more strongly than DBBA and polyanthryl with the Au(110) substrate, as a result of their flatter conformation.

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Ada Della Pia, Giulia Avvisati, Oualid Ourdjini, Claudia Cardoso, Daniele Varsano, Deborah Prezzi, Andrea Ferretti, Carlo Mariani, Maria Grazia Betti. 2017-04-21. Electronic Structure Evolution during the Growth of Graphene Nanoribbons on Au(110). https://doi.org/10.1021/acs.jpcc.5b11884

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