CAREER: Directed Self-Assembly of Block Copolymers by High Magnetic Fields

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。技术摘要：该提案概述了一个5年计划，该计划以使用磁场的嵌段共聚物（BCP）的定向自组装为中心，并使用对齐材料作为半导体纳米线合成的模板。今天吗？美国的材料科学是建立在控制多尺度物质结构的能力之上的。冶金学和陶瓷科学的历史说明了这种能力的演变到今天？的块体和薄膜单晶生长工艺。相比之下，聚合物科学的发展轨迹是新生的-令人惊讶的是，仍然缺乏用于加工具有受控粒度和取向的BCP的实用和可扩展的方法。这些能力的缺乏阻碍了利用功能BCP和纳米复合材料的自组装的新技术的开发，例如在非线性光学材料、膜和光致发光材料中。这一建议直接解决了上述差距。它采用了一种新的方法，通过使用高磁场，使用专用的仪器进行关键的原位研究的层次有序的聚合物系统中的对齐动力学定向自组装。它需要合理的设计材料的基础上定制自组装微域之间的接口，并追求使用大面积薄膜模板的垂直对齐的纳米线的合成，作为实现理想的光伏几何形状的一个步骤。目标是：（1）用于场取向的模型液晶BCP的合理设计、合成和表征;（2）通过原位散射和非原位显微镜定量研究材料的温度和场依赖性取向;（3）在宏观场取向BCP膜中合成化合物半导体CdS和ZnS。非技术性总结：拟议的工作将有助于在光电子学，非线性光学和膜等领域的新兴技术解决方案。它专门针对可用于下一代太阳能电池的半导体材料的生产。该项目将包括通过学生和PI的访问与国家实验室，国家高磁场实验室的互动。指导学生研究人员是这项建议的一个重要组成部分。特别是，所有受资助的学生积极参与地方、区域和国家的科学界，将成为他们培训的一个组成部分，并将加强他们终身学习的愿望。拟议的工作构成了PI以聚合物材料科学为中心的新教学和推广的基础。PI将继续提供一门新的高分子物理课程，其中包括一个实验模块。PI将在社区一级针对初中和高中学生以及耶鲁大学代表性不足的学生开展外展活动。通过与纽黑文科学博览会的合作，为当地高中科学教师提出了一个新的夏季研究计划。 总体影响如下：（1）发展太阳能电池应用的基础科学;（2）对本科生和研究生进行材料科学和聚合物科学教育;（3）编制新的材料/聚合物科学课程;（4）改进对中学生和教师的材料科学培训;（5）在本科生和研究生一级征聘和指导代表性不足的群体;（6）使新的研究人员在各个层次上积极融入其科学界。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).TECHNICAL SUMMARY:This proposal outlines a 5-year plan centered on the directed self-assembly of block copolymers (BCPs) using magnetic fields, and the use of aligned materials as templates for the synthesis of semiconducting nanowires. Today?s materials science is predicated on the ability to control the structure of matter on multiple length scales. The history of metallurgy and ceramic science illustrate the evolution of this capability through to today?s bulk and thin film single crystal growth processes. The trajectory in polymer science is nascent by comparison - surprisingly, practical and scalable methods for processing BCPs with controlled grain size and orientation are still lacking. The absence of these capabilities hampers the development of new technologies that harness the self-assembly of functional BCPs and nanocomposites such as in non-linear optical materials, membranes and photovoltaics. This proposal directly addresses the above mentioned gap. It takes a novel approach to directed self-assembly via the use of high magnetic fields using a dedicated instrument to conduct critical in-situ studies of alignment dynamics in a hierarchically ordered polymer system. It entails rational design of materials based on tailoring interfaces between self-assembled microdomains and pursues the synthesis of perpendicularly aligned nanowires using large-area thin film templates as a step towards the realization of ideal photovoltaic geometries. The objectives are: (1) Rational design, synthesis and characterization of model liquid crystalline (LC) BCPs for field alignment; (2) Quantitative studies of temperature and field-dependent alignment of materials via in-situ scattering and ex-situ microscopy; (3) Synthesis of compound semiconductors CdS and ZnS within macroscopically field-aligned BCP films. NON-TECHNICAL SUMMARY:The proposed work will contribute to emerging technology solutions in fields such as photovoltaics, non-linear optics and membranes. It specifically takes aim at the production of semiconducting materials which can be used for next generation solar cells. The project will include interactions with a national lab, the National High Magnetic Field Lab, via visits by students and the PI. Mentoring student researchers is an important component of this proposal. In particular, active participation of all supported students in the community of science locally, regionally and nationally will be an integral part of their training and will strengthen their desire for lifelong learning. The proposed work forms the basis for a new teaching and outreach thrust by the PI centered on polymer materials science. A new course on Polymer Physics which includes a lab module will continue to be offered by the PI. The PI will engage in outreach targeting middle and high school students at the community level, and under-represented students at Yale. Through partnership with the New Haven Science Fair, a new summer research program for local high school science teachers has been proposed. The impacts overall are: (1) Development of fundamental science with applications in solar cells; (2) Education of undergraduate and graduate students in materials science and polymer science; (3) Development of new materials/polymer science curriculum; (4) Improved materials science training of middle-high school students and teachers; (5) Recruitment and mentoring of underrepresented groups at the undergraduate and graduate level; (6) Strong integration of new researchers into their science community at all levels.