Chemistry and Electrochemistry of Molecule-Like Nanoparticles

教授罗伊斯W.位于查佩尔山的北卡罗来纳州大学的Murray得到了分析和表面化学项目的支持，研究金属纳米颗粒，重点是直径从3 nm到略低于1 nm的颗粒。 重点是推进技术的制备和表征的单层保护的金属簇（MPC），化合物，具有金属，或金属样，通过保护单分子层的硫醇配体稳定的核心。 研究的目标尺寸范围内的金属纳米颗粒位于块状金属和离散分子之间的过渡区域，并表现出依赖于核心尺寸和保护单层的化学性质的性质。 该研究小组正在探索用于制备MPC的合成策略，这些MPC越来越小，更高度单分散，并且能够改变金属核心组成和配体官能团（荧光团，氧化还原基团和分析有用的结合位点）。 正在开发分析方法，特别关注高效液相色谱（HPLC）分离和光学和电化学检测策略，阐明MPC的大小分散性。 不同大小的MPC的电子转移化学的能量学和动力学正在探索通过最大的MPC，显示一个连续的电子充电，较小的MPC，显示量子化的双层充电和最小的核心MPC，表现出分子一样的homo/lumo带隙的响应之间的比较。 此外，还对金属核的配体单层上的配体交换反应和荧光团的激发态行为进行了研究。本研究为研究溶液中金属簇的金属-分子过渡区开发了必要的工具。 这项工作在应用领域产生了影响，包括化学传感和电子电荷传输的纳米级管道的开发。

Professor Royce W. Murray of the University of North Carolina at Chapel Hill is supported by the Analytical and Surface Chemistry program to investigate metal nanoparticles with emphasis on particles in the range from 3 nm to just below 1 nm in diameter. Focus is on advancing techniques for the preparation and characterization of monolayer-protected metal clusters (MPCs), compounds that have metal, or metal-like, cores stabilized by protecting monolayers of thiolate ligands. Metal nanoparticles in the size range targeted for study lie in the transition region between bulk metals and discrete molecules and exhibit properties that are dependent on both core size and the chemical nature of the protecting monolayer. The research team is exploring synthetic strategies for the preparation of MPCs that are increasingly smaller and more highly mono-disperse and enable variations in metal core composition and ligand functional groups (fluorophores, redox groups, and analytically useful binding sites). Analytical methods are being developed with special focus on high performance liquid chromatographic (HPLC) separations and tactics of optical and electrochemical detection that elucidate MPC size dispersity. The energetics and dynamics of electron transfer chemistry of differently sized MPCs are being explored through comparisons between responses of the largest MPCs that display a continuum of electronic charging, smaller MPCs that display quantized double layer charging and the smallest core MPCs that exhibit molecule-like homo/lumo band gaps. Ligand exchange reactions and the excited state behavior of fluorophores attached to the ligand monolayer of the metal core are also being investigated.This research is developing tools necessary to study the metal-to-molecule transition region of metal clusters in solution. The work has impact in application areas that include chemical sensing and the development of nanometer-scale conduits for electronic charge transport.