CAREER: Directed Nanoparticle Growth by Oriented Aggregation and Elucidating the Link between Reactivity and Particle Size, Shape, and Microstructure

明尼苏达大学双子城分校的R.Lee Penn教授得到了分析和表面化学计划以及地质和古生物学计划的支持，通过定向聚集机制研究晶体、纳米级过渡金属氧化物和氢氧化物的形成。这种机制包括通过特定的结晶学平面附着的方式组装初级晶体。重点是通过操纵晶体表面性质来控制定向聚集。除了纳米颗粒的生长外，还通过溶解和氧化还原反应的研究来探索这些材料的化学性质。颗粒结构主要由X射线衍射、电子显微镜和光子相关光谱测量确定。佩恩教授还为中学生和科学教育工作者开发了一个项目，旨在提高人们对原子水平上材料结构的认识。实施以晶体生长和表征为中心的实验室练习，以帮助学生和教育工作者理解材料的宏观性质和潜在的原子级结构之间的关系。对无机氧化物晶体生长和通过溶解和氧化还原反应分解晶体的研究有助于深入了解通过大气和地质化学影响自然环境的过程。该教育计划为中学生和教育工作者提供学习机会，以提高对大宗材料性质和原子能级结构之间关系的认识。

Professor R. Lee Penn of the University of Minnesota-Twin Cities is supported by the Analytical and Surface Chemistry Program and the Geology and Paleontology program to investigate the formation of crystalline, nanometer-scale, transition metal oxides and hydroxides through the mechanism of oriented aggregation. This mechanism involves the assembly of primary crystals by attachment through specific crystallographic planes. Emphasis is on the control of orientated aggregation through manipulation of crystal surface properties. In addition to nanoparticle growth, chemical properties of these materials are probed through the study of dissolution and redox reactions. Particle structure is determined primarily by x-ray diffraction, electron microscopy and photon correlation spectroscopy measurements. Professor Penn is also developing a program for middle school students and science educators designed to enhance awareness of the structure of materials at the atomic level. Laboratory exercises that center on crystal growth and characterization are implemented to assist students and educators in understanding relationships between the macroscopic properties of materials and the underlying atomic level structure. Studies of inorganic oxide crystal growth and crystal decomposition through dissolution and redox reactions is providing insights into processes that affect the natural environment through atmospheric and geological chemistry. The education plan is providing learning opportunities for middle school age students and educators to enhance awareness of relationships between bulk materials properties and atomic level structure.