On Heavier Chalcogen (Se and Te) Interfacial Chemistry and Charge Transfer in Monolayer-Protected Metal Nanoparticles

单层保护金属纳米粒子中重硫族元素（Se 和 Te）界面化学和电荷转移

• 批准号: 1413429
• 负责人: YuYe Tong
• 金额: $ 49万
• 依托单位: Georgetown University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-15 至 2018-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1413429&HistoricalAwards=false
• 关键词: Heavier; Chalcogen; Se; Te; Interfacial

Metal nanoparticles are metal particles of very small (nanometer scale) dimensions. They possess novel chemical and physical properties that are very different from those of large particles or bulk metals. Dr. YuYe Tong of Georgetown University and Dr. Thomas Allison at the National Institute of Standards and Technology conduct research to gain a better understanding of the structural parameters that govern the properties of metal nanoparticles. The long-term goal is to harness the novel properties of nanoparticles for practical applications (such as electronic or optical devices, biomedical diagnosis, and drug delivery). This project provides interdisciplinary research opportunities to students, training them in the use of the state-of-the-art instruments for studying nanoparticles. Through Georgetown University's partnership with the Cesar Chavez Public Charter Schools in Southeast Washington DC, which have very high population of students of underrepresented groups or from low-income families, Dr. Tong participates in a project to help develop new chemistry curricula for local charter schools. This project serves as a springboard to attract more women and underrepresented students to STEM fields.Dr. Tong and Dr. Allison explore the use of heavier chalcogen (Se and Te) as alternative anchoring elements to the prevailingly used sulfur for attaching organic molecular wires to metal surfaces. Using a combination of experimental techniques and Density Functional Theory (DFT) computations, they aim to gain a better mechanistic understanding of the metal-chalcogenolate interfacial chemistry and its ramifications on charge transfer/transport in single monolayer-protected nanoparticle (MPN) and MPN assemblies. Specifically, this research entails: 1) the synthesis of different sizes (1 to 5 nm) of nanoparticles of different metal elements (Au, Ag, Cu, Pt, and Pd), which are protected with ligands of different organic backbones (alkyl and aryl), alkyl chain lengths (C6, C8, and C12), and anchoring chalcogen elements (Se and Te); 2) the characterization of the afore-synthesized MPNs by in situ electrochemical (EC) spectroscopic (NMR/IR/Raman) techniques and ex situ X-ray photoemission spectroscopy; and 3) comparative mechanistic investigations of charge transfer through a single MPN and MPN assemblies using EC scanning tunneling microscopy and traditional EC measurements.

金属纳米颗粒是非常小（纳米尺度）尺寸的金属颗粒。 它们具有新型的化学和物理特性，与大颗粒或散装金属的化学和物理特性截然不同。 乔治敦大学的Yuye Tong博士和美国国家标准技术研究所的Thomas Allison博士进行研究，以更好地了解控制金属纳米粒子特性的结构参数。 长期目标是利用纳米颗粒的新特性用于实际应用（例如电子或光学设备，生物医学诊断和药物输送）。 该项目为学生提供了跨学科的研究机会，培训他们使用最先进的仪器来研究纳米颗粒。 通过乔治敦大学与华盛顿特区东南部的塞萨尔·查韦斯公立特许学校的合作，该学校的人数很高，人数不足的团体或低收入家庭的学生，汤汤博士参加了一个项目，以帮助开发当地租赁学校的新化学课程。 该项目是一个跳板，吸引更多女性和代表性不足的学生进入STEM Fields.dr。 Tong和Allison博士探索了使用较重的chalcogen（SE和TE）用作广泛使用的硫的替代锚定元素，用于将有机分子电线连接到金属表面上。 它们结合了实验技术和密度功能理论（DFT）计算，旨在更好地了解金属 - 氨基盐介质界面化学及其对单个单层保护的纳米颗粒（MPN）和MPN组件中电荷转移/运输的影响。 具体而言，这项研究需要：1）不同尺寸（1至5 nm）的不同金属元素（1至5 nm）的纳米颗粒（AU，AG，AG，CU，CU，PT和PD）的合成，这些纳米颗粒受到不同有机骨架（烷基和芳基），烷基链长（C6，C8，C8，C12）和CH的配体保护的，这些配体受到不同有机骨架（烷基和芳基）的配体的保护； 2）通过原位电化学（EC）光谱（NMR/IR/RAMAN）技术和Ex X射线光发射光谱法对上述合成的MPN进行表征； 3）使用EC扫描隧道显微镜和传统的EC测量通过单个MPN和MPN组件对电荷转移的比较机械研究。