Collaborative Research: Excited State Dynamics of Structurally Precise Metal Nanoclusters

合作研究：结构精确的金属纳米团簇的激发态动力学

• 批准号: 1507909
• 负责人: Christine Aikens
• 金额: $ 28万
• 依托单位: Kansas State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-15 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1507909&HistoricalAwards=false
• 关键词: Collaborative; Research; Excited; State; Dynamics

These awards by the Macromolecular/Supramolecular/Nanochemistry Program in the Division of Chemistry to Christine Aikens (Kansas State University), Ken Knappenberger (Florida State University), and Chris Ackerson (Colorado State University) develop the ability to predict how metal particles with dimensions on the order of one-billionth of a meter (i.e., nanoparticles) interact with light. Such metal nanoparticles may, in the long term, become functional components in solar-to-electric energy conversion devices, optical sensors, and medical diagnostics and therapeutics, among others. Currently, the lack of understanding how light provokes energy flow through these materials limits their applications. The collaborative team combines cutting-edge theoretical and experimental spectroscopy along with precision nanoparticle synthesis and characterization. They facilitate their multi-disciplinary research project by developing graduate student training courses focused on modeling, measurement, and preparation of structurally precise photonic nanoparticles. The team is also strongly engaged in outreach to K-12 students and educators; is actively involved in incorporating research into the undergraduate curricula at each of their respective universitie;, and is committed to the involvement of underrepresented students in scientific research and education.The primary thrusts of this effort are to determine how electronic energy relaxation affects the nanophotonic properties of structurally precise metal nanoparticles in the 1-2 nm size domain. The research features an emergent class of nanophotonic materials: monolayer-protected clusters (MPCs), which can be synthesized and isolated with atomic precision. These materials represent an intermediate class of materials between bulk metallic materials and smaller photo-excited molecules. The program of study provides nanoparticle-specific descriptions for fundamental processes involved such as electron-phonon coupling, which are critical for determining the functional properties of nanophotonic materials. The research investigates the interplay between MPC structural parameters and electronic relaxation. The specific objectives are: 1) to determine the mechanisms of electron-phonon and electron-vibrational coupling and their influence on the electronic relaxation dynamics of Au25(SR)18 MPCs, where SR is an alkanethiol; 2) to understand the effects of metal doping on MPC dynamics; 3) to describe how electron-phonon coupling changes with increasing MPC dimensions; and 4) to investigate the influence of MPC ligand band structure on electron dynamics.

这些奖项由堪萨斯州立大学的克里斯汀·艾肯斯、佛罗里达州立大学的肯·克纳彭伯格和科罗拉多州立大学的克里斯·阿克森获得化学系的高分子/超分子/纳米化学计划颁发，旨在发展预测尺寸在十亿分之一米量级的金属颗粒(即纳米颗粒)如何与光相互作用的能力。从长远来看，这种金属纳米颗粒可能会成为太阳能到电能转换设备、光学传感器、医疗诊断和治疗等领域的功能部件。目前，由于缺乏对光如何激发能量流通过这些材料的了解，限制了它们的应用。合作团队将尖端的理论和实验光谱学以及精确的纳米颗粒合成和表征结合在一起。他们通过开发研究生培训课程来促进他们的多学科研究项目，重点是建模、测量和制备结构上精确的光子纳米颗粒。该团队还致力于与K-12学生和教育工作者的接触；积极参与将研究纳入各自大学的本科课程；并致力于让未被充分代表的学生参与科学研究和教育。这一努力的主要目的是确定电子能量驰豫如何影响结构精确的金属纳米颗粒在1-2纳米尺寸范围内的纳米光子性质。这项研究以一类新兴的纳米光子材料为特色：单层保护的团簇(MPC)，它可以被合成并以原子精度分离。这些材料代表了介于大块金属材料和较小的光激发分子之间的中间类材料。该研究计划为所涉及的基本过程提供了纳米粒子特有的描述，如电子-声子耦合，这些过程对于确定纳米光子材料的功能特性至关重要。研究了MPC结构参数与电子弛豫之间的相互作用。具体目标是：1)确定AU25(SR)18 MPC的电子-声子和电子-振动耦合机制及其对电子驰豫动力学的影响；2)了解金属掺杂对MPC动力学的影响；3)描述电子-声子耦合如何随着MPC尺寸的增加而变化；以及4)研究MPC配体结构对电子动力学的影响。

项目成果

Electronic relaxation dynamics in [Au 25 (SR) 18 ] −1 (R = CH 3 , C 2 H 5 , C 3 H 7 , MPA, PET) thiolate-protected nanoclusters

[Au 25 (SR) 18 ] â1 (R = CH 3 , C 2 H 5 , C 3 H 7 , MPA, PET) 硫醇盐保护的纳米团簇中的电子弛豫动力学

• DOI: 10.1039/c9cp04039k
• 发表时间: 2020
• 期刊: Physical Chemistry Chemical Physics
• 影响因子: 3.3
• 作者: Senanayake, Ravithree D.;Aikens, Christine M.
• 通讯作者: Aikens, Christine M.

Toward quantitative electronic structure in small gold nanoclusters

小型金纳米团簇的定量电子结构

• DOI: 10.1063/5.0055210
• 发表时间: 2021
• 期刊: The Journal of Chemical Physics
• 作者: Fagan, Jonathan W.;Weerawardene, K. L. Dimuthu M.;Cirri, Anthony;Aikens, Christine M.;Johnson, Christopher J.
• 通讯作者: Johnson, Christopher J.

Geometrical and Electronic Structure, Stability, and Optical Absorption Spectra Comparisons between Thiolate- and Chloride-Stabilized Gold Nanoclusters

• DOI: 10.1021/acs.jpca.9b06598
• 发表时间: 2019-11-14
• 期刊: JOURNAL OF PHYSICAL CHEMISTRY A
• 影响因子: 2.9
• 作者: Kuda-Singappulige, Gowri U.;Aikens, Christine M.
• 通讯作者: Aikens, Christine M.