Tuning Carbon Nanotube Band Gaps by Guanine Functionalization

罗伯特教授B。William Marsh Rice University的Weisman由化学系的大分子，超分子和纳米化学计划支持，以研究和控制与DNA连接的单壁碳纳米管的性质。这些纳米管是人造纳米材料的一个突出家族，其不寻常的特性和潜在用途可以导致新的科学发现和在医疗保健，能源和基础设施安全领域的有用的现实应用。该项目基于Weisman及其同事发现的一种反应，该反应将DNA结合到纳米管上，形成具有可控光学和电子特性的稳定混合结构。研究人员将使用实验和计算来进一步探索这些纳米管-DNA杂交体的性质，并研究它们在生物医学传感和量子信息处理中的应用潜力。除了这些研究目标外，该项目还将在多个层面上推进科学教育。从事该项目的研究生将获得基本的实践培训，并将发展口头和书面技术交流技能。本科生参与研究将获得宝贵的研究经验。韦斯曼实验室还将在夏季举办高中教师在一个正在进行的计划，扩大他们的知识，并导致丰富的科学课程影响数百名高中学生。这个项目将加深我们对单线态O2诱导的鸟嘌呤核碱基与碳纳米管之间的独特共价反应的理解。该反应通过引入密集的浅激子陷阱阵列来扰乱纳米管电子结构，浅激子陷阱的间距和深度可以通过选择ssDNA寡聚结构来控制。因此，它有可能产生具有工程带隙的纳米管混合物。由分子动力学和量子化学计算支持的实验将研究1）敏化剂和纳米管之间的相互作用如何影响共价反应; 2）DNA和纳米管之间的化学键合; 3）杂化物中光谱增宽的来源; 4）控制功能化程度的参数。这些结果将有助于阐明杂化物的详细结构和功能化反应的机理。还将确定有效形成所需产物的最佳条件。定制的DNA功能化纳米管样品将被准备用于有针对性的合作项目，以进一步探测其特性，并探索其在量子光学和生物医学传感中的可能应用。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Professor Robert B. Weisman of William Marsh Rice University is supported by the Macromolecular, Supramolecular and Nanochemistry Program of the Division of Chemistry to investigate and control the properties of single-wall carbon nanotubes linked to DNA. These nanotubes are a prominent family of artificial nanomaterials whose unusual properties and potential uses can lead to new scientific discoveries and useful real-world applications in the areas of health care, energy, and infrastructure safety. This project is based on the discovery by Weisman and co-workers of a reaction that bonds DNA to nanotubes to form stable hybrid structures that have controllable optical and electronic properties. The investigators will use experiments and computations to further explore the nature of these nanotube-DNA hybrids and to examine their potential for use in biomedical sensing and quantum information processing. Apart from these research goals, the project will advance science education at several levels. Graduate students working on the project will gain essential hands-on training and will develop skills in oral and written technical communication. Undergraduate students participating in the studies will get valuable research experience. The Weisman lab will also host high school teachers during the summers in an ongoing program that expands their knowledge and leads to enriched science curricula affecting hundreds of high school students. This project will deepen our understanding of the unique covalent reaction between guanine nucleobases and carbon nanotubes induced by singlet O2. This reaction perturbs the nanotube electronic structure by introducing a dense array of shallow excitonic traps whose spacing and depth can be controlled by the choice of ssDNA oligo structure. It thus has the potential to produce nanotube hybrids with engineered band gaps. Experiments supported by molecular dynamics and quantum chemical computations will investigate 1) how interactions between sensitizer and nanotube affect the covalent reaction; 2) the chemical bonding between DNA and nanotube; 3) the source of spectral broadening in the hybrids; 4) the parameters controlling functionalization extent. The results will clarify the detailed structures of the hybrids and the mechanism of the functionalization reaction. Optimal conditions for efficient formation of the desired products will also be identified. Customized DNA-functionalized nanotube samples will be prepared for targeted collaborative projects to further probe their properties and explore possible applications in quantum optics and biomedical sensing.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.