Cai Liangliang, Yu Xin, Liu Mengxi, Sun Qiang, Bao Meiling, Zha Zeqi, Pan Jinliang, Ma Honghong, Ju Huanxin, Hu Shanwei, Xu Liang, Zou Jiacheng, Yuan Chunxue, Jacob Timo, Björk Jonas, Zhu Junfa, Qiu Xiaohui, Xu Wei
Interdisciplinary Materials Research Center, College of Materials Science and Engineering , Tongji University , Caoan Road 4800 , Shanghai 201804 , People's Republic of China.
CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience , National Center for Nanoscience and Technology , Beijing 100190 , People's Republic of China.
ACS Nano. 2018 Aug 28;12(8):7959-7966. doi: 10.1021/acsnano.8b02459. Epub 2018 Jul 24.
Conductive polymers are of great importance in a variety of chemistry-related disciplines and applications. The recently developed bottom-up on-surface synthesis strategy provides us with opportunities for the fabrication of various nanostructures in a flexible and facile manner, which could be investigated by high-resolution microscopic techniques in real space. Herein, we designed and synthesized molecular precursors functionalized with benzal gem-dibromomethyl groups. A combination of scanning tunneling microscopy, noncontact atomic force microscopy, high-resolution synchrotron radiation photoemission spectroscopy, and density functional theory calculations demonstrated that it is feasible to achieve the direct formation of C-C double-bonded structural motifs via on-surface dehalogenative homocoupling reactions on the Au(111) surface. Correspondingly, we convert the sp-hybridized state to an sp-hybridized state of carbon atoms, i. e., from an alkyl group to an alkenyl one. Moreover, by such a bottom-up strategy, we have successfully fabricated poly(phenylenevinylene) chains on the surface, which is anticipated to inspire further studies toward understanding the nature of conductive polymers at the atomic scale.
导电聚合物在各种与化学相关的学科和应用中具有重要意义。最近开发的自下而上的表面合成策略为我们以灵活简便的方式制造各种纳米结构提供了机会，这些纳米结构可以通过高分辨率显微镜技术在实空间中进行研究。在此，我们设计并合成了用苯亚甲基偕二溴甲基官能化的分子前体。扫描隧道显微镜、非接触原子力显微镜、高分辨率同步辐射光电子能谱和密度泛函理论计算相结合表明，通过在Au(111)表面上进行表面脱卤均偶联反应直接形成C-C双键结构单元是可行的。相应地，我们将碳原子的sp杂化态转变为sp杂化态，即从烷基转变为烯基。此外，通过这种自下而上的策略，我们成功地在表面上制备了聚（亚苯基乙烯基）链，这有望激发进一步研究以在原子尺度上理解导电聚合物的本质。
