Self-Assembly of Plasmonic Nanoclusters Mediated by Localized Steric Repulsion

局域空间排斥介导的等离激元纳米团簇的自组装

• 批准号: 1236309
• 负责人: Lilo Pozzo
• 金额: $ 29.23万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-07-15 至 2016-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1236309&HistoricalAwards=false
• 关键词: Self; Assembly; Plasmonic; Nanoclusters; Mediated

1236309PI: PozzoThe implementation of new technologies harnessing plasmonic effects depends strongly on improving our capacity to reliably and economically produce complex structures from nanoscale metallic building blocks. Unfortunately, the organization of large quantities of nanomaterials via ?bottom-up? strategies that are scalable, cost-effective and that achieve precise structure control is still limited. This project will research a new strategy to assemble complex structures from nanoparticle building blocks by exploiting local steric repulsion and short-ranged attraction. In this new approach, the formation of structured clusters or will be controlled through the use of engineered nanoparticle surfaces containing mixtures of end-grafted polymers to regulate steric repulsion and small functional molecules to induce attraction. Steric repulsion and attractive interactions will be precisely adjusted by altering the surface composition to control particle assembly and to manipulate the morphology of the multi-particle structures. Diverse colloidal clusters with controllable optical and electronic properties will be generated using this robust strategy. Small angle scattering of x-rays and neutrons will be used to selectively probe the nanoparticle configuration (SAXS) and the conformation of the polymers (SANS) in order to develop a complete and self-consistent description of the assembly process. Structural experiments will be complemented by direct comparisons to simulations. The primary goals of the project will be to: 1) Experimentally determine the role of polymer interactions in mediating nanoparticle self-assembly 2) Reduce the structural polydispersity of self-assembled clusters 3) Predict equilibrium cluster structures with Monte Carlo simulations and 4) Increase the structural diversity of colloidal molecules. Achieving these objectives will contribute significantly to the advancement of plasmonic applications that utilize nanoparticle clusters. Plasmonic technologies exploit the unique interactions between visible light and delocalized electron clouds in small metallic particles. For example, plasmonic effects are used to develop sensors for the rapid identification of trace amounts of chemicals and environmental contaminants in complex samples. They also advance less invasive and more effective medical diagnostic and treatments tools such as photoacoustic imaging and photothermal cancer therapy. Plasmonic approaches are also used to develop advanced solar cells that are more efficient and less expensive than current technologies. Nonetheless, the successful deployment of these and other applications requires significant advances in the scalable fabrication of nanostructures with controllable optical and electronic properties. This project will research a new approach that is suitable to fabricate large numbers of plasmonic nanomaterials while maintaining accurate structure control and with methods that are scalable, robust and versatile.

1236309PI：新技术的实施，利用等离子效应的新技术在很大程度上取决于提高我们可靠和经济地从纳米级金属构建块中生产复杂结构的能力。不幸的是，通过自下而上的纳米材料组织大量纳米材料？可扩展，具有成本效益并实现精确结构控制的策略仍然有限。该项目将通过利用局部空间排斥和短期吸引力来研究一种新的策略，从纳米颗粒构建块中组装复杂的结构。在这种新方法中，结构化簇的形成或将通过使用含有端接聚合物的混合物的工程纳米颗粒表面来控制，以调节空间排斥和小功能分子来引起吸引力。空间排斥和有吸引力的相互作用将通过改变表面组成来控制颗粒组件并操纵多粒子结构的形态来精确调整。具有可控的光学和电子特性的多种胶体簇将使用这种强大的策略生成。 X射线和中子的小角度散射将用于选择性探测纳米颗粒构型（SAXS）和聚合物（SANS）的构象，以开发对组装过程的完整且一致的描述。结构实验将通过直接比较模拟来补充。该项目的主要目标是：1）实验确定聚合物相互作用在介导纳米粒子自组装中的作用2）减少自组装簇的结构多分散性3）预测与蒙特卡洛模拟的平衡簇结构和4）增加胶体分子的结构多样性。实现这些目标将对利用纳米颗粒簇的等离子应用的发展产生重大贡献。等离子技术利用了小金属颗粒中可见光和离域电子云之间的独特相互作用。例如，血浆效应用于开发传感器，以快速鉴定复杂样品中的痕量化学物质和环境污染物。他们还可以降低侵入性和更有效的医学诊断和治疗工具，例如光声成像和光热癌症治疗。等离子方法还用于开发比当前技术更有效且价格便宜的高级太阳能电池。尽管如此，这些应用程序和其他应用的成功部署仍需要在具有可控光学和电子特性的纳米结构的可扩展制造方面取得重大进展。该项目将研究一种适合制造大量等离子纳米材料的新方法，同时保持准确的结构控制以及可扩展，健壮和多功能的方法。