CAREER: Evaporation-Driven Self-Assembly of Hierarchically Ordered Structures from Confined Solutions

0844084Z林特的目标，这个职业生涯的建议是开发一个简单的，但强大的，一步的方法，通过蒸发创建纳米结构材料的层次顺序在一个精确的可控的方式，免除了光刻技术和外部领域的需要。为了实现这一目标，提出了两个具体目标：（1）通过在微观尺度上的蒸发驱动的自组装和在纳米尺度上的自发自组装的协同作用来创建分级有序的结构;以及（2）开发理论模型来理解结构形成的机制。我们打算设计由二嵌段共聚物或量子点（QD）在纳米级自组装组成的分级结构，可以作为多功能材料在光学，电子，光电和传感材料和器件中的潜在应用。通过在不同长度尺度上组合两个或更多个自组装过程来产生分级有序结构，即，通过受限几何形状中的不可逆溶剂蒸发的动态自组装（即，平面上弯曲的几何形状）和纳米级的二嵌段共聚物或QD的自发自组装。这种方法利用并行自组装作为将独特的纳米材料精确组织成空间有序结构的手段。研究结果将在纳米材料科学的更广泛背景下进行处理，并用于纳米科学和纳米技术教育。将开展综合教育活动，使包括K-12学生在内的广泛受众了解这种新的纳米科学和纳米技术知识，从而促进对其重要性的普遍认识。拟议研究的智力价值体现在利用限制几何的创新研究中（即，平上曲线几何形状）作为控制蒸发液滴内流动的独特环境，这又在一个步骤中调节良好有序的结构形成。所提出的CAREER项目是重要的，因为它将导致一种新的范例，用于以简单、可控和具有成本效益的方式在表面上创建分层有序的结构（即，潜在的变革性研究），用于光子学、电子学、光电子学、生物传感器、纳米技术和生物技术的潜在应用。因此，预计研究成果将对纳米材料科学的进步做出重大贡献。拟议工作的更广泛影响包括加强各级纳米科学和纳米技术教育。将为高年级本科生和低年级研究生开发一门新的纳米结构聚合物材料课程。将从爱荷华州州立大学的妇女科学与工程项目（PWSE）招募女本科生进行夏季纳米材料研究，从而加强了该项目中代表性不足的群体的参与。暑期讲习班将为K-12教师创建，反过来，他们将与学生分享新信息。高中女实习生将为全国五至八年级学生制定关于聚合物纳米材料和纳米晶体的网络课程计划。这项活动最终将使中小学生接触纳米世界。这个CAREER项目产生的知识可能会导致创造新的设备和材料，由于纳米级构建块的分层排列，这些设备和材料具有独特的功能，从而将基础科学发现转变为有益于社会的有用技术。

0844084Z. LinThe goal of this CAREER proposal is to develop a simple, yet robust, one-step method via evaporation for creating nanostructured materials with hierarchical order in a precisely controllable manner, dispensing with the need for lithographic techniques and external fields. To achieve this goal, two specific objectives are proposed: (1) create hierarchically ordered structures via the synergy of evaporation-driven self-assembly at the microscopic scale and spontaneous self-assembly at the nanoscopic scale; and (2) develop theoretical models to understand the mechanisms of structure formation. We intend to design hierarchical structures consisting of either diblock copolymers or quantum dots (QDs) self-assembled at the nanoscale that can serve as multifunctional materials for potential applications in optical, electronic, optoelectronic, and sensing materials and devices. Hierarchically ordered structures are produced by combining two or more self-assembling processes on different length scales, i.e., dynamic self-assembly via irreversible solvent evaporation in restricted geometries (i.e., curve-on-flat geometries) at the microscopic scale and spontaneous self-assembly of diblock copolymers or QDs at the nanoscale. This approach utilizes concurrent self-assemblies as a means to precisely organize unique nanomaterials into spatially ordered structures. The research findings will be treated within the broader context of nanomaterials science and utilized for nanoscience and nanotechnology education. Integrated educational activities will be developed to expose a wide range of audiences, including K-12 students, to this new nanoscience and nanotechnology knowledge, thereby promoting general awareness of its importance. The intellectual merit of the proposed research is manifested in the innovative studies of exploiting restricted geometries (i.e., curve-on-flat geometries) as unique environments for controlling flow within an evaporating droplet, which, in turn, regulates the well-ordered structure formation in one step. The proposed CAREER project is significant because it will lead to a new paradigm for creating hierarchically ordered structures on surfaces in a simple, controllable, and cost-effective manner (i.e., potentially transformative research) for potential applications in photonics, electronics, optoelectronics, biosensors, nanotechnology, and biotechnology. The outcomes from the research are thus expected to make significant contributions to the advancement of nanomaterials science. The broader impact of the proposed work includes stronger nanoscience and nanotechnology education across several levels. A new course on Nanostructured Polymeric Materials for senior undergraduate and junior graduate students will be developed. Female undergraduate students will be recruited for summer nanomaterials research from Iowa State University's Program for Women in Science and Engineering (PWSE), thus strengthening the involvement of an underrepresented group in the project. Summer workshops will be created for K-12 teachers who, in turn, will share the new information with their students. Web-based lesson plans on polymeric nanomaterials and nanocrystals will be developed by female high school interns for 5th-8th graders nationwide. This activity will ultimately expose elementary and middle school students to the nano-world. Knowledge generated by this CAREER project may lead to the creation of novel devices and materials that exhibit unique functions due to hierarchical arrangement of nanoscopic building blocks, thereby transitioning fundamental scientific discoveries into useful technologies that benefit society.