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

0844084Z。林这份职业建议书的目标是开发一种简单、但强大的一步法，通过蒸发以精确可控的方式创建具有分级顺序的纳米结构材料，而不需要光刻技术和外部磁场。为了实现这一目标，提出了两个具体的目标：(1)通过微观尺度上的蒸发驱动自组装和纳米尺度上的自发自组装的协同作用来创建层次化有序结构；(2)建立理论模型来理解结构形成的机制。我们打算设计由两嵌段共聚物或在纳米尺度上自组装的量子点(量子点)组成的分级结构，作为多功能材料在光学、电子、光电子和传感材料和器件中潜在的应用。层次化有序结构是通过将两个或多个不同长度尺度上的自组装过程结合在一起而形成的，即在微观尺度上通过受限几何(即平曲线几何)中的不可逆溶剂挥发实现的动态自组装，以及在纳米尺度上两嵌段共聚物或量子点的自发自组装。这种方法利用并行的自组装作为一种手段，将独特的纳米材料精确地组织成空间有序的结构。研究成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学生在内的广大受众接触到这一新的纳米科学和纳米技术知识，从而提高对其重要性的普遍认识。拟议研究的智力价值体现在创新研究中，即利用受限几何图形(即平面线几何图形)作为独特的环境来控制蒸发液滴内的流动，这反过来又在一步中调节有序结构的形成。拟议的职业项目意义重大，因为它将导致一种新的范式，以一种简单、可控和成本效益高的方式在表面上创建分层有序结构(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，这项研究的成果有望为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在几个层面上加强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。爱荷华州立大学女性科学与工程项目(PWSE)将招收女性本科生进行夏季纳米材料研究，从而加强该项目中代表性不足的群体的参与。将为K-12教师创建暑期讲习班，他们将与学生分享新的信息。关于聚合物纳米材料和纳米晶体的网络课程计划将由女高中实习生为全国5-8年级的学生开发。这项活动最终将使中小学生接触到纳米世界。通过这个职业项目产生的知识可能会导致由于纳米结构块的分级安排而产生展示独特功能的新型设备和材料的创造，从而将基本的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.