On-Surface Synthesis of Pentagon-Incorporated Graphene-Like Nanoribbons with Multiple Precursors.

Graphene nanoribbons (GNRs) and their derivatives are receiving increasing attention as a result of their unique electronic and magnetic properties, and many novel derivative structures have been fabricated. The carbon pentagon plays a crucial role in determining both geometric structures and electronic properties of carbon-based materials. Here, we demonstrate that carbon-pentagon-incorporated graphene-like nanoribbons (GLNRs), which are an important class of GNR derivatives, are successfully fabricated via the Ullmann coupling and aromatic cyclodehydrogenation reaction on the surface by a suitable choice of multiple tailored molecular precursors. Our approach provides a basis for the impact of adatoms in the reaction and proves the steering function of the aryl-metal interaction in procedures of self-assembly and organometallic state. In addition, this study paves the way for on-surface synthesis of GNRs and their derivatives as well as the fine tuning of electronic properties of carbon nanoarchitectures by manipulating the edge structures and embedding carbon pentagon heterojunctions.