A Novel Architectural Approach to the Organic Synthesis of Short Segments of Carbon Single-Walled Nanotubes with Well-Defined Lengths, Diameters and Chiral Vectors

有机合成具有明确长度、直径和手性矢量的碳单壁纳米管短段的新颖结构方法

• 批准号: 1048365
• 负责人: Thomas Hughes
• 金额: $ 10.34万
• 依托单位: Siena College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-06-01 至 2013-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1048365&HistoricalAwards=false
• 关键词: Novel; Architectural; Approach; Organic; Synthesis

With this award, the Organic and Macromolecular Chemistry Program supports the work of Professor Thomas S. Hughes of the University of Vermont. This research involves carrying out novel synthetic approaches to carbon single-walled nanotube segments with specific and controllable structural parameters such as the length, diameter and chiral vector, or the orientation of the six-membered rings of carbon atoms relative to the axis of the tube. These approaches to the strained nanotube segments rely on the synthesis of planar, unstrained phenylene macrocycles containing alkyne or cyclopentadienone functional groups. These planar macrocycles will be synthesized and then additional phenyl groups will be added using a Diels-Alder cycloaddition. The phenyl groups are introduced in an arrangement that will allow a subsequent oxidation reaction to fuse the rings together into the target tubular structures. Control over the diameter and length of the product nanotubes will be achieved by controlling the diameter of the precursor macrocycle and the size of the auxiliary phenyl-containing reactants. The strain inherent in the nanotube segments will thus be incorporated in a highly incremental fashion. Once synthesized, the solid-state packing and the conductivity of the nanotube segments will be evaluated. Chemical modifications of the segments will also be performed analogous to those currently carried out on larger nanotubes with less well-defined structures; such chemical modifications of these model systems will elucidate the chemical events taking place in the larger nanotubes.The broader impacts of this project are in part the training of graduate students in organic synthesis and characterization, and in the characterization of organic materials. In addition, the product nanotube segments are models of the larger carbon single-walled nanotubes currently produced with relatively little control over their diameters and lengths. The segments produced by the method proposed may be suitable as "seeds" for the production of large amounts of nanotubes with specific structures. Since the structure of the carbon nanotube affects its potential usefulness as a material for organic electronic applications such as field-effect transistors, light-emitting diodes and photovoltaics, these smaller model systems could be used to further the understanding of the physical bases of these phenomena and could be potential feedstocks for materials in eventual devices.

有机和高分子化学项目通过该奖项支持佛蒙特大学托马斯·S·休斯教授的工作。 这项研究涉及对碳单壁纳米管段进行新颖的合成方法，该碳单壁纳米管段具有特定且可控的结构参数，例如长度、直径和手性矢量，或碳原子六元环相对于管轴的方向。 这些制备应变纳米管片段的方法依赖于含有炔或环戊二烯酮官能团的平面、非应变亚苯基大环化合物的合成。 这些平面大环将被合成，然后使用狄尔斯-阿尔德环加成添加额外的苯基。 苯基基团以允许随后的氧化反应将环熔合在一起形成目标管状结构的排列方式引入。 对产物纳米管的直径和长度的控制将通过控制前体大环的直径和辅助含苯基反应物的尺寸来实现。 因此，纳米管段固有的应变将以高度增量的方式并入。 合成后，将评估纳米管段的固态堆积和电导率。 对这些片段的化学修饰也将类似于目前对结构不太明确的较大纳米管进行的化学修饰进行；这些模型系统的这种化学修饰将阐明较大纳米管中发生的化学事件。该项目的更广泛影响部分在于对研究生进行有机合成和表征以及有机材料表征方面的培训。 此外，产品纳米管段是目前生产的较大碳单壁纳米管的模型，对其直径和长度的控制相对较少。 通过所提出的方法生产的片段可能适合作为生产大量具有特定结构的纳米管的“种子”。 由于碳纳米管的结构影响其作为场效应晶体管、发光二极管和光伏等有机电子应用材料的潜在用途，因此这些较小的模型系统可用于进一步了解这些现象的物理基础，并可能成为最终设备中材料的潜在原料。