Synthesis of Nonplanar Graphene Nanoribbon with Fjord Edges

• Published in: Journal of the American Chemical Society Vol. 143; no. 15; pp. 5654 - 5658
• Main Authors: Yao, Xuelin, Zheng, Wenhao, Osella, Silvio, Qiu, Zijie, Fu, Shuai, Schollmeyer, Dieter, Müller, Beate, Beljonne, David, Bonn, Mischa, Wang, Hai I, Müllen, Klaus, Narita, Akimitsu
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 21.04.2021; Amer Chemical Soc
• Subjects: Chemistry; Chemistry, Multidisciplinary; Communication; Physical Sciences; Science & Technology
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/jacs.1c01882

As a new family of semiconductors, graphene nanoribbons (GNRs), nanometer-wide strips of graphene, have appeared as promising candidates for next-generation nanoelectronics. Out-of-plane deformation of π-frames in GNRs brings further opportunities for optical and electronic property tuning. Here we demonstrate a novel fjord-edged GNR (FGNR) with a nonplanar geometry obtained by regioselective cyclodehydrogenation. Triphenanthro-fused teropyrene 1 and pentaphenanthro-fused quateropyrene 2 were synthesized as model compounds, and single-crystal X-ray analysis revealed their helically twisted conformations arising from the [5]­helicene substructures. The structures and photophysical properties of FGNR were investigated by mass spectrometry and UV–vis, FT-IR, terahertz, and Raman spectroscopic analyses combined with theoretical calculations.