Self-assembled nanostructures of a series of linear oligothiophene derivatives adsorbed on surfaces

查看全文 作　　者：Xuan [1,2]Peng;Ting [1,2]Meng;Lilei [3]Wang;Linxiu [1,2]Cheng;Wenchao [1,2]Zhai;Ke [1]Deng;Chang-Qi [3]Ma;Qingdao [1,2]Zeng 机构地区：[1]CAS Key Laboratory of Standardization and Measurement for Nanotechnology,CAS Center for Excellence in Nanoscience,National Center for Nanoscience and Technology(NCNST),Beijing 100190,China;[2]Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China;[3]Printable Electronics Research Center,Suzhou Institute of Nano-Tech and Nano-Bionics,Chinese Academy of Sciences,Suzhou 215123,China 出　　处：《Chinese Chemical Letters》索引2023年第34卷第2期,共6页 基　　金：financially supported by the National Basic Research Program of China (No. 2017YFA0205000);the National Natural Science Foundation of China (No. 21972031);the Strategic Priority Research Program of Chinese Academy of Sciences (No. XDB36000000)。 摘　　要：Many previous studies have shown that the molecular structures of oligothiophene derivatives including molecular skeleton and alkyl chains have a significant effect on their self-assemblies on the surface.In this work, a series of linear oligothiophene derivatives(DCV-n T-Hex, n = 3~11) modified with terminal dicyanovinyls and alkyl chains were adopted to further investigate the different assembly behaviors at liquid-solid interface by scanning tunneling microscopy(STM). Interestingly, via the hydrogen bonding and van der Waals interactions, DCV-3T-Hex formed zigzag and flower structures while DCV-n T-Hex(n = 4~11) formed lamellar structures. Density functional theory(DFT) calculations show that for the most energetically favorable configurations of DCV-n T-Hex, the different distribution of alkyl chains affected intermolecular interactions, and ultimately led to the different assembled structures. The zigzag and flower structures of DCV-3T-Hex had preferential thermodynamic stability compared to other structures of DCV-n T-Hex(n = 4~11). In addition, self-assembled nanostructures of DCV-n T-Hex molecules with even numbers(n = 4, 6, 8, 10) were overall more stable than those with odd numbers(n = 5, 7, 9,11), and the stability of the self-assembled structure was weakened with the extension of the molecular backbone, individually. The orientation of molecular alkyl chains was found to greatly affect the intermolecular interactions and thus leading to various self-assembly structures of DCV-n T-Hex(n = 3~11). 关 键 词：Oligothiophene derivatives Scanning tunneling microscopy Supramolecular self-assembly Van der Waals force DFT calculations