Fabrication of sulfur-doped cove-edged graphene nanoribbons on Au(111)

• 作者: Huan Yang Yixuan Gao Wenhui Niu Xiao Chang Li Huang Junzhi Liu Yiyong Mai Xinliang Feng Shixuan Du Hong-Jun Gao
• 来源期刊: 中国物理B（英文版）
• 年，卷（期）: 2021,（7）
• 所属期刊栏目: CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC,AND OPTICAL PROPERTIES
• 页码范围: 551-556
• 页数: 6页
• 语种: 英文
• DOI: 10.1088/1674-1056/abfbd0

摘要

The on-surface synthesis from predesigned organic precursors can yield graphene nanoribbons (GNRs) with atomi-cally precise widths,edge terminations and dopants,which facilitate the tunning of their electronic structures.Here,we report the synthesis of novel sulfur-doped cove-edged GNRs (S-CGNRs) on Au(111) from a specifically designed precur-sor containing thiophene rings.Scanning tunneling microscopy and non-contact atomic force microscopy measurements elucidate the formation of S-CGNRs through subsequent polymerization and cyclodehydrogenation,which further result in crosslinked branched structures.Scanning tunneling spectroscopy results reveal the conduction band minimum of the S-CGNR locates at 1.2 eV.First-principles calculations show that the S-CGNR possesses an energy bandgap of 1.17 eV,which is evidently smaller than that of an undoped cove-edged GNR (1.7 eV),suggesting effective tuning of the bandgap by introducing sulfur atoms.Further increasing the coverage of precursors close to a monolayer results in the formation of linear-shaped S-CGNRs.The fabrication of S-CGNRs provides one more candidate in the GNR toolbox and promotes the future applications of heteroatom-doped graphene nanostructures.