Sub-nanometer Optical Imaging and Self-Assembly on Plasmonic Metals

等离子金属的亚纳米光学成像和自组装

• 批准号: RGPIN-2022-03088
• 负责人: McLean, Alastair
• 金额: $ 2.04万
• 依托单位: Queen's University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=763251
• 关键词: Sub; nanometer; Optical; Imaging; Self

My group's long-term goal is to use the capabilities of scanning probes, such as the two new state-of-the-art scanning probe microscopes described in this proposal, to address critical research questions in nanophotonics and surface chemistry/physics. In this proposal, two research questions/themes are identified and described. Theme 1: Towards atomic optical imaging with quantum optical plasmonics By combining scanning tunnelling microscopy with optical spectroscopy, it has been demonstrated that photoluminescence and also Raman images of single molecules can be acquired with sub--nanometer spatial resolution. These results dramatically illustrate how plasmonic materials can enhance optical processes and they also represent an important step towards atomic optical resolution. With theorists at Queen's, our goal is to develop and test a quantum mechanical model of the optical enhancement in photoluminescence and tip---enhanced Raman imaging that includes the opto-mechanical coupling between the vibrating molecules and the plasmon resonance. We will perform optical imaging of model systems, including molecules and atomically precise nano-clusters, using a cryogenic nano--optical microscope. Atomically sharp tips will be selected using non-contact atomic force microscopy with a qPlus sensor. The impact will be fundamental insights into plasmon enhancement that could potentially have applications for nanoscale optical devices, an important technology market in North America. Theme 2: Self--assembly of N--heterocylic carbenes on plasmonic metals Although the self--assembly of organic molecules on metallic surfaces is one of the most powerful methods for patterning at the nanometer scale, the thermal and oxidative instability of commonly used thiol-based self-assembled monolayers are significant impediments to their widespread commercial use in plasmonic optical devices. With collaborators in Chemistry, we have demonstrated that N--heterocyclic carbenes (NHCs) represent a viable alternative to thiols. Our goal is to optimize the stability of these new overlayer systems by systematically modifying the structure of the NHCs and concurrently developing a molecular--level understanding of their surface chemistry, self--assembly methods and protocols. The impact will be an optimized next generation functionalizing agent for metal surfaces based on NHCs that can be used as a surface modifier with applications in molecular electronics, microcontact printing, biosensing and surface protection. The insights gained through the study of NHC self-assembly on surfaces will also inform the synthesis of NHC-stabilized metal nanoclusters that are used in medicine and catalysis. This proposal will provide training for a total of 18 students at the following levels: 2 PhD, 6 MSc, 5 undergraduate summer students, and 5 final year honours theses.

我的团队的长期目标是利用扫描探针的功能，例如本提案中描述的两种最先进的新型扫描探针显微镜，来解决纳米光子学和表面化学/物理学中的关键研究问题。在该提案中，确定并描述了两个研究问题/主题。主题1：利用量子光学等离子体实现原子光学成像通过将扫描隧道显微镜与光学光谱相结合，已经证明可以以亚纳米空间分辨率获取单分子的光致发光和拉曼图像。这些结果戏剧性地说明了等离子体材料如何增强光学过程，它们也代表了原子光学分辨率的重要一步。 我们的目标是与女王大学的理论家一起开发和测试光致发光和尖端增强拉曼成像光学增强的量子力学模型，其中包括振动分子和等离子共振之间的光机械耦合。我们将使用低温纳米光学显微镜对模型系统（包括分子和原子级精确的纳米团簇）进行光学成像。将使用带有 qPlus 传感器的非接触式原子力显微镜来选择原子锋利的尖端。 其影响将是对等离激元增强的基本见解，这可能会应用于纳米级光学设备，这是北美的一个重要技术市场。 主题 2：N-杂环卡宾在等离子体金属上的自组装虽然有机分子在金属表面上的自组装是纳米级图案化最有力的方法之一，但常用的热和氧化不稳定性基于硫醇的自组装单分子层是其在等离子体光学器件中广泛商业应用的重大障碍。 我们与化学领域的合作者证明，N-杂环卡宾 (NHC) 是硫醇的可行替代品。我们的目标是通过系统地修改 NHC 的结构并同时开发对其表面化学、自组装方法和协议的分子水平理解来优化这些新覆盖层系统的稳定性。 该影响将是基于 NHC 的优化的下一代金属表面功能化剂，可用作表面改性剂，应用于分子电子学、微接触印刷、生物传感和表面保护。通过表面 NHC 自组装研究获得的见解也将为用于医学和催化的 NHC 稳定金属纳米团簇的合成提供信息。 该提案将为总共 18 名学生提供以下级别的培训：2 名博士、6 名硕士、5 名本科暑期学生和 5 篇期末荣誉论文。