Abstract
Atomically precise graphene nanoribbons (GNRs) attract great interest because of their highly tunable electronic, optical, and transport properties. However, on-surface synthesis of GNRs is typically based on metal surface-assisted chemical reactions, where metallic substrates strongly screen their designer electronic properties and limit further applications. Here, we present an on-surface synthesis approach to forming atomically precise GNRs directly on semiconducting metal oxide surfaces. The thermally triggered multistep transformations preprogrammed in our precursors' design rely on highly selective and sequential activations of carbon-bromine (C-Br) and carbon-fluorine (C-F) bonds and cyclodehydrogenation. The formation of planar armchair GNRs terminated by well-defined zigzag ends is confirmed by scanning tunneling microscopy and spectroscopy, which also reveal weak interaction between GNRs and the rutile titanium dioxide substrate.
| Original language | English |
|---|---|
| Pages (from-to) | 571-575 |
| Number of pages | 5 |
| Journal | Science |
| Volume | 369 |
| Issue number | 6503 |
| DOIs | |
| State | Published - Jul 31 2020 |
Funding
This work was supported in part by the Center for Nanophase Materials Sciences (CNMS), which is a U.S. Department of Energy Office of Science User Facility (M.K., W.K., A.-P.L.). Research was partially funded by grants ONR N00014-16-1-3213 and ONR N00014-20-1-2302 from the University of Tennessee (W.K., A.-P.L.). Preliminary research was supported by the Polish Ministry of Science and Higher Education, contract no. 0341/IP3/2016/74 (I.I.). A.K.S. and K.A. thank the Deutsche Forschungsgemeinschaft for financial support (Projektnummer 182849149−SFB 953 A6 and AM407).