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石墨烯纳米丝带来自齐格扎克边缘封装的聚 (para-2,9-dibenzo[bc,kl]coronenylene) 聚合物链
Doreen Beyer1, Shiyong Wang2,3, Carlo A Pignedoli2
1Center for Advancing Electronics Dresden (cfaed) and Faculty of Chemistry and Food Chemistry, Chair for Molecular Functional Materials , Dresden University of Technology , 01062 Dresden , Germany.
Journal of the American Chemical Society
|February 8, 2019
概括
研究人员合成了一种新型聚合物,聚二乙烯 (PPDBC),并将其融为曲边缘扩展的石墨烯纳米带 (zeeGNR). 这些纳米带由于其独特的结构和可调节的带间隙,显示出电子应用的潜力.
科学领域:
- 材料科学
- 有机化学
- 纳米技术
背景情况:
- 聚乙烯 (PPP) 是一个已被广泛研究的聚合物,但其曲边缘类型的研究较少.
- 石墨烯纳米带 (GNR) 根据其宽度和边缘结构提供可调节的电子特性.
- 在表面合成提供了一个强大的途径来创造精确定义的纳米结构.
研究的目的:
- 为了实现曲边缘封装聚合物的自下而上的合成,聚乙烯 (PPDBC).
- 研究PPDBC链的横向融合到曲边缘延伸的石墨烯纳米带 (zeeGNRs).
- 描述合成聚合物和GNR的结构和电子特性.
主要方法:
- 设计和合成二化二甲基甲烯.
- 热诱导的表面辅助聚合和循环脱.
- 使用扫描道显微镜 (STM) 和非接触式原子力显微镜 (nc-AFM) 的结构特征.
- 使用准粒子方法进行电子带隙计算.
主要成果:
- 在表面成功合成PPDBC,其曲边缘含量高 (70%).
- 带宽为N=9至N=17个碳原子的PPDBC链向zeeGNR进行侧面融合.
- ZeeGNR 呈现出高曲 (67%) 和椅子 (25%) 边缘段的比例.
- 对 zeeGNR 计算的电子频段间隙低至 0.9 eV.
结论:
- 这项研究证明了一种合成PPDBC并随后形成zeeGNR的可行方法.
- 合成的 zeeGNR 具有高比例的曲边缘和狭窄的电子带间隙.
- 这些发现为创建具有定制电子特性的新型石墨烯纳米结构开辟了道路.
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