Control Nanoparticle Patterning via Asymmetric Functionalization

美国国家科学基金会-化学与化工运输系统颗粒与多阶段工艺计划(1415年)提案编号：0730738主要研究人员：李，克里斯托弗隶属：德雷克塞尔大学提案标题：通过不对称官能化智能优点控制纳米颗粒图案化。将纳米颗粒组装成所需的图案是将这些迷人的材料应用于许多实际应用的主要障碍之一。合成定制的不对称功能化NPs(AFNPs)是克服这一障碍的关键。我们最近开发了一种聚合物单晶模板法来合成AFNPs。采用表面带有官能团的聚合物单晶对纳米粒子进行功能化处理。这些晶体的固态性质导致了不对称官能化。在拟议的研究中，我们的目标是进一步探索这种方法来合成各种AFNPs，并将它们组装成不同的结构，以满足不同的应用。具体目标是：1)合成各种控制良好、具有不同光学和电学性质的AFNPs。一些精心挑选的官能团(包括-OH、-COOH、NH2和不同的聚合物)将与这些AFNPs偶联。还将合成含NP的三嵌段共聚物。将特别致力于合成只有一个聚合链连接到NP上的单官能化NPs。2)将上述量身定做的AFNPs组装成各种结构。AFNPs可以被视为人造原子。通过使用具有适当官能团的配体，它们可以选择性地与其他配体结合并形成簇(人造分子)。将合成含有一种或两种NPs的NP二聚体、H2O形状的簇合物和NP链。含NP的三嵌段共聚物的自组装也将被研究。通过仔细调节三嵌段共聚物的结构，可以形成ABCCBA片层和核壳圆柱体等纳米结构。该方法是实现多种AFNPs的一种通用方法。与AFNP领域的最新进展相比，我们所提出的研究的关键优势在于使用聚合物单晶作为偶联反应的固体基质。使用这种独特的底物的好处可以概括如下。(1)聚合物单晶为AFNP的合成提供了可逆的衬底；多功能也是可行的；(2)可以获得可控的NP面密度的单层或多层NP薄膜；(3)也可以获得单官能化的NP；(4)可以容易地制备各种NP复合体，如二聚体、H2O形状的NP和NP链(Ho-NP和co-NP链)。这项研究旨在解决纳米技术领域的一个具有挑战性的问题。如果成功，这将有助于将许多令人着迷的NP推向市场。该提案的教育部分包括：(1)通过开发将在“纳米结构聚合物材料”课程中使用的“纳米杂化材料”模块，满足对聚合物纳米科学和纳米技术现代发展的教育需要。(2)让高中生和教师，特别是代表不足的人群，参与拟议的研究活动。这些拟议的教育活动具有广泛的影响。首先，拟议的计划将通过一系列辅导计划让高中生和教师参与研究活动，从而帮助弥合教育发展水平之间的现有差距。其次，由于费城地区代表不足的群体人口众多，拟议的外联计划将专门针对鼓励代表不足的人群参与。第三，拟议的研究将通过科学媒体和公共研讨会进行宣传。这一信息的传播以及中学教育教师的实践经验将使更多有见识的教师能够通过与周边费城地区的学区建立合作努力来教育未来。

National Science Foundation - Division of Chemical &Transport Systems Particulate & Multiphase Processes Program (1415)Proposal Number: 0730738 Principal Investigators: Li, Christopher Affiliation: Drexel University Proposal Title: Control Nanoparticle Patterning via Asymmetric Functionalization Intellectual Merit. Assembling nanoparticles (NPs) into desired patterns is one of the major hurdles to bringing these fascinating materials into many practical applications. Synthesizing tailor-made, asymmetrically functionalized NPs (AFNPs) holds the key to overcoming this hurdle. We recently developed a polymer-single-crystal-templating method to synthesize AFNPs. Polymer single crystals with functional groups on the crystal surface were used to functionalize NPs. The solid state nature of these crystals renders the asymmetric functionalization. In the proposed research, we aim to further explore this method to synthesize a variety of AFNPs and assemble them into various structures for different applications. The specific objectives are: 1) to synthesize a variety of well-controlled AFNPs with different optical and electronic properties. A number of carefully selected functional groups (including -OH,-COOH, NH2 and different polymers) will be coupled with these AFNPs. NP-containing triblock copolymers will also be synthesized. Special efforts will be devoted to synthesizing monofunctionalized NPs where only one polymer chain is attached to the NP. 2) to assemble the above tailor-made AFNPs into various structures. The AFNPs can be regarded as artificial atoms. By using ligands with proper functional groups, they can selectively bond with others and form a cluster (artificial molecule). NP dimers, H2O-shaped clusters and NP chains containing one or two types of NPs will be synthesized. Self-assembly of the NP-containing triblock copolymers will also be investigated. Nanostructures such as ABCCBA lamellar and core-shell cylinder could be formed by carefully tuning the triblock copolymer structures. The approach method is a generic way to achieve a variety of AFNPs. Compared to the state-of-the-art in the AFNP field, the key advantage of our proposed research is using polymer single crystals as the solid substrate for coupling reaction. The benefits of using this unique substrate can be summarized as the follows. (1) The polymer single crystal provides a reversible substrate for AFNP synthesis; multifunctionality is also feasible; (2) Free standing mono- or multi-layer NP films can be obtained with controlled NP areal density; (3) Monofunctionalized NPs can also be achieved; (4) A variety of NP complexes such as dimers, H2O-shaped NPs and NP chains (both homo-NP and co-NP chain) can be readily fabricated.Broader Impact. The research aims to tackle a challenging problem in the nanotechnology field. If successful, it could help to bring many fascinating NPs into the market place. The educational component of the proposal includes: (1) Addressing the need for the education of modern developments in polymer nanoscience and nanotechnology by developing "Nanohybrid Materials" modules which will be used in the "Nanostructured Polymeric Materials" course. (2) Involving high school students and teachers, particularly under-represented populations, in the proposed research activities. These proposed educational activities encompass a broad impact. First, the proposed plan will help bridge the existing gap between levels of educational developments by involving high school students and teachers in research activities through a number of mentoring programs. Second, due to the high population of underrepresented groups in the Philadelphia region, the proposed outreach program will be specifically geared towards encouraging the participation of under-represented populations. Third, the proposed research will be publicized through scientific media and public workshops. The dissemination of this information along with hands on experiences for secondary education teachers will result in more informed teachers capable of educating the future by establishing collaborative efforts with school districts in the surrounding Philadelphia region.