NIRT: Size Dependence of Phase Transitions in Nanocrystalline Oxides

该提案是应“纳米科学与工程”（NSF 01-157）的要求提交的。 本研究计划旨在探讨：1）固体材料响应温度、压力、电磁场或机械应变而发生的结构-性能变化或相变的本质; 2）氧化物纳米晶体相变的尺寸依赖性，重点是相变过程中的电子和晶格动力学; 3）界面能和应变的影响;（4）压力、温度、杂质掺杂和缺陷密度对相稳定性的影响。这些研究将为纳米氧化物材料提供多维相图。除了培养研究生和博士后学者在先进的研究技术相关的科学和技术，化学，材料科学和物理研究问题的结合将提供一个智力丰富的教育环境。该项目汇集了来自化学，材料科学和物理学的教师，博士后学者和研究生的多机构团队，以探索纳米材料及其在技术中的可能用途。通过范德比尔特大学的探索网站的推广将向公众展示这个NSF项目。与欧文管理研究生院的联系将结合到纳米科学和纳米技术的快速增长的商业利益中。了解氧化物纳米晶体的结构相变对许多重要材料技术领域的发展至关重要，这些领域包括催化，分离技术，磷光体材料，薄膜电子学，光子学和环境修复。在这些领域接受培训的学生将非常有利地竞争学术，工业和政府实验室部门感兴趣的高优先领域的工作。该项目由材料研究部，化学部，物理部以及化学和运输系统部共同支持。

This proposal was submitted in response to the solicitation "Nanoscale Science and Engineering" (NSF 01-157). This research project aims to explore: 1) the nature of structure-property changes or phase transitions that occur in solid materials in response to temperature, pressure, electromagnetic fields or mechanical strain; 2) the size dependence of phase transitions in oxide nanocrystals, focusing on electronic and lattice dynamics during the phase transition; 3) the effects of interfacial energy and strain; and 4) the influence of pressure, temperature, impurity doping and defect density on phase stability. These studies will produce a multi-dimensional phase diagrams for nanoscale oxide materials. In addition to training graduate students and postdoctoral scholars in advanced research techniques relevant both to science and technology, the combination of chemistry, materials science and physics research issues will provide an intellectually rich educational environment. The project brings together a multi-institutional team of faculty, postdoctoral scholars and graduate students from chemistry, materials science and physics to explore nanoscale materials and their possible uses in technology. Outreach through Vanderbilt University's Explorations Web site will showcase this NSF project for the general public. Connections to the Owen Graduate School of Management will couple into the rapidly growing business interests in nanoscience and nanotechnology.Understanding structural phase transformations in oxide nanocrystals is important to the development of a number of important materials technology areas that include catalysis, separation technologies, phosphor materials, thin-film electronics, photonics, and environmental remediation. Students trained in these areas will compete very favorably for jobs in high priority areas of interest to the academic, industrial, and government laboratory sectors. This project is co-supported by the Division of Materials Research, the Chemistry Division, the Physics Division, and the Chemical and Transport Systems Division.