Study of Transition Metal-Carbon Mixed Clusters: From Gas Phase to Condensed Phase

9622733王这个项目将研究气相中金属碳化物团簇(MxCy，其中M是金属，C是元素碳)的结构和形成，以及这些团簇在凝聚相中形成的纳米材料。气相研究涉及阴离子光电子能谱，这将在很大的尺寸范围内提供对MxCy团簇结构和成键的基本了解。这项技术对碳和不同过渡金属之间在成键和结构上的细微差异也很敏感。凝聚相研究包括用一种新的激光蒸发沉积技术制备MxCy纳米团簇样品，并用各种现代显微镜(电子显微镜、扫描隧道显微镜、原子力显微镜)进行表征。气相研究将深入了解三类新材料的形成机理：面内金属富勒烯、单壳碳纳米管和金属羧基。通过气相和凝聚相相结合的研究，本项目有可能发现具有新的电子和催化性质的新的碳-金属纳米簇合物，以及合成它们的有效方法。该项目涉及巴特尔太平洋西北实验室的主要合作工作。该项目由凝聚态物理计划和原子、分子和光学物理计划NSF共同资助。碳和金属形成了一类具有特殊性能的金属碳化物材料，可用于制造速度更快的计算机的电子材料、催化，如汽车催化转化器，以及工具硬化制造过程。当材料由被称为纳米簇的小碳化物颗粒组成时，这些性能可以得到增强或修改，其中一些是由新的、稳定的金属-碳分子组成的。本项目研究了这种碳化物纳米粒子的形成机制和新的金属-碳分子形式，并将研究这些团簇独特的物理和化学性质。了解形成机制将导致更有效的方法来定制具有所需性质的纳米团簇的设计。该项目涉及巴特尔太平洋西北实验室的主要合作工作。该项目由凝聚态物理计划和原子、分子和光学物理计划NSF共同资助。***

9622733 Wang This project will investigate the structure and formation of metal carbide clusters (MxCy, where M is a metal and C is elemental carbon) in the gas phase, as well as the nanomaterials formed by these clusters in the condensed phase. The gas phase study involves anion photoelectron spectroscopy, which will provide fundamental understanding of the structure and bonding of the MxCy clusters in a wide size range. The technique is also sensitive to subtle differences in bonding and structures between carbon and different transition metals. The condensed phase study involves preparation of MxCy nanocluster samples by a novel laser vaporization deposition technique and characterization using various modern microscopies (TEM, STM, AFM). The gas phase studies will lead to insight into the formation mechanisms of three classes of novel materials: endohedral metallo-fullerenes, single-shell carbon nanotubes, and metallo-carbohedrenes. Through the combined gas phase and condensed phase studies, this project has the potential to discover new carbon-metal nanoclusters with novel electronic and catalytic properties and efficient methods to synthesize them. The project involves major collaborative work at the Battelle Pacific Northwest Laboratories. The project is co-funded between the Condensed Matter Physics Program and the Atomic, Molecular and Optical Physics Program NSF. %%% Carbon and metals form a class of metal carbide materials with unusual properties that find applications in electronic materials for making faster computers, in catalysis, such as automobile catalytic converters, and in tool hardening manufacturing processes. These properties can be enhanced or modified when the materials are made of small carbide particles, called nanoclusters, some of which are composed of new, stable metal-carbon molecules. This project investigates the mechanisms of formation of such carbide nanoparticles and the new metal-carbon molecular forms, and al so will study the unique physical and chemical properties of these clusters. Understanding the formation mechanisms will lead to more efficient methods to tailor the design of the nanoclusters with desired properties. The project involves major collaborative work at the Battelle Pacific Northwest Laboratories. The project is co-funded between the Condensed Matter Physics Program and the Atomic, Molecular and Optical Physics Program NSF. ***