Synthesis and Reversible Self-Assembly of Monodisperse Plasmonic Nanorods Permanently Ligated with Photoresponsive Polymers

在这个由化学学部大分子、超分子和纳米化学项目资助的项目中，佐治亚理工学院材料科学与工程学院的林志群教授正在开发一种新型纳米材料，这种材料的表面含有对光敏感的聚合物。纳米颗粒是非常微小的颗粒，大约比人类头发“细”500-100,000倍。然而，它们的表面积与体积比要比传统材料（如钢铁、木材、混凝土或塑料）大几个数量级。事实上，仅仅几克这样的粒子就能有一个足球场那么大的面积。以可控的方式结合纳米颗粒来创造具有有用性能的材料通常是非常繁琐和具有挑战性的合成任务。这项工作通过在纳米颗粒表面使用精确设计的聚合物，大大简化了纳米颗粒组装成材料的过程。当这些聚合物被光驱动纳米粒子激活时，它们以一种受控的方式结合在一起，从而起到光开关的作用。这种聚合物结构和化学的控制有可能提供重要的知识，影响有用的刺激响应技术的发展，这种技术经常出现在用于高速互联网的光缆、耐用的“智能织物”、光传感器，甚至是癌症治疗中的药物输送中。通过开展以学生教育为重点的若干活动和项目，特别是妇女和来自代表性不足群体的学生，这项工作产生了更广泛的影响。研究小组正在进一步扩大他们工作的影响，包括来自大亚特兰大地区的高中教师，并为他们提供指导。本文主要研究了光响应聚合物永久连接的单分散等离子体纳米棒的合成和可逆自组装。创新和高度变革的策略集中在(a)设计和制作单分散聚合物系住等离子体金纳米棒和纳米管，并精确控制其尺寸，(b)系统探索其结构依赖的光学特性，以及(c)研究和光响应聚合物紧密和永久覆盖的粒子自组装，以及相应的可逆光学特性。从该项目中获得的知识有可能影响光学、光电子学、催化、传感材料和设备、能量转换、药物输送、纳米技术和生物技术等领域的技术发展。该奖项反映了美国国家科学基金会的法定使命，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。

In this project funded by the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry, Professor Zhiqun Lin of the School of Materials Science and Engineering at the Georgia Institute of Technology is developing a new class of nanomaterials which contain polymers on their surfaces that are responsive to light. Nanoparticles are very tiny particles about 500-100,000 times "thinner" than a human hair. However, they have surface area to volume ratios orders of magnitudes larger than seen in traditional materials such as steel, wood, concrete or plastic. As a matter of fact, just a couple of grams of such particles can have an area as enormous as a football field. Combining nanoparticles in a controlled manner to create materials with useful properties is often very tedious and challenging synthetic task. This work greatly simplifies the assembly of nanoparticles into materials by utilizing precisely designed polymers on their surfaces. These polymers when activated by light drive nanoparticles to combine in a controlled manner and therefore act as a photo-switch. Such control by a virtue of polymer architecture and chemistry has the potential to provide important knowledge that could impact the development of useful stimuli-responsive technologies that are often seen in optical cables used for high speed internet, durable "smart fabrics", light sensors, and even drug delivery in cancer therapy. The work has a broader impact through the development of several activities and programs that focus on education of students, especially women and students from underrepresented groups. The research team is further broadening the impact of their work by including and mentoring high school teachers from the greater Atlanta area.This research is focused on the synthesis and reversible self-assembly of monodisperse plasmonic nanorods permanently ligated with photo-responsive polymers. The innovative and highly transformative strategy is focused on (a) designing and crafting monodisperse polymer-tethered plasmonic gold nanorods and nanotubes with accurate control over their dimension, (b) systematic exploration of their structure-dependent optical properties and (c) investigation into light-enabled self-assembly of particles intimately and permanently capped with photo-responsive polymers, and accordingly the reversible optical properties. The knowledge gained from the project has the potential to impact the development of technologies with applications in optics, optoelectronics, catalysis, sensory materials and devices, energy conversion, drug delivery, nanotechnology and biotechnology.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.