CAREER: Linking the Forward and Reverse Vapor-Liquid-Solid Mechanisms to Synthesize Ordered Integrated Metal Oxide Nanostructures

职业：连接正向和反向气-液-固机制来合成有序集成金属氧化物纳米结构

• 批准号: 1455154
• 负责人: Beth Guiton
• 金额: $ 62.5万
• 依托单位: University of Kentucky Research Foundation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2021-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1455154&HistoricalAwards=false
• 关键词: CAREER; Linking; Forward; Reverse; Vapor

Non-technical Description.We live in a society with reliance on materials, in particular those that enable the generation or storage of energy, for which the efficiencies that are required are ever growing. The function of such materials increasingly relies on creating highly-efficient and closely-spaced crystal interfaces including, for example, large area p-n junction arrays for solar devices. This project to understand and exploit the solid-iquid-vapor mechanism should provide a new approach to engineer nanostructured composite materials with highly efficient single-crystalline components, thus having a significant positive impact on the directed design of metal oxide materials, and on the society that relies on them. Based on this research and the infrastructure developed to support it, are a series of educational and outreach activities, designed to increase participation in research experiences by University of Kentucky undergraduates.Technical Description.Though the vapor-liquid-solid (VLS) mechanism has been extensively studied in its role in metal-catalyzed nanowire growth, the reverse of this process - the solid-liquid-vapor (SLV) mechanism - is not well understood, yet it could well provide the key to understanding and utilizing VLS-grown wires. Thus, there is a critical need to determine the key factors governing the SLV mechanism and its fundamental relationship to VLS growth. The objective in this project is to determine the key parameters that govern the SLV mechanism in metal oxides, and the relationship linking SLV to the VLS mechanism. The central hypothesis is that if a single metal nanodroplet can be used in the VLS growth of a nanowire, it will also catalyze the SLV dissolution of the same material, with crystallographic specificity equivalent to that of the original growth. The rationale is that a greater understanding of SLV and its relation to VLS could provide a route to highly-specified porous materials, as well as a method of precise placement for high-quality nanowires synthesized with a "bottom-up" approach. The successful completion of these studies is expected to have a significant positive impact on the directed design of functional metal oxide materials since it will enable the production of structures, compositions, and arrangements of interfaces with a high degree of control and complexity. This research is significant because combining SLV with VLS will for the first time enable control of the nanowire-template interface, essentially "synthesizing" interfaces with specific chemistry, crystallography, and spacing.

非技术描述。我们生活在一个依赖材料的社会，特别是那些能够产生或储存能源的材料，其效率要求不断提高。这种材料的功能越来越依赖于创造高效和紧密间隔的晶体界面，例如，用于太阳能器件的大面积pn结阵列。本项目对固-液-气机制的理解和开发，将为设计具有高效单晶组分的纳米结构复合材料提供新的途径，从而对金属氧化物材料的定向设计以及依赖于它们的社会产生重大的积极影响。基于这项研究和为支持它而开发的基础设施，有一系列的教育和推广活动，旨在增加肯塔基大学本科生对研究经验的参与。技术描述。虽然蒸汽-液-固（VLS）机制在金属催化纳米线生长中的作用已被广泛研究，但该过程的相反过程-固体-液-蒸气（SLV）机制尚未得到很好的理解，但它可以为理解和利用VLS生长的纳米线提供关键。因此，迫切需要确定控制SLV机制的关键因素及其与VLS生长的基本关系。本项目的目的是确定控制金属氧化物中SLV机制的关键参数，以及SLV与VLS机制之间的关系。中心假设是，如果单个金属纳米液滴可以用于纳米线的VLS生长，它也会催化相同材料的SLV溶解，其晶体学特异性相当于原始生长的晶体学特异性。其基本原理是，对SLV及其与VLS的关系的更深入的了解，可以为高度指定的多孔材料提供一条途径，以及用“自下而上”的方法合成高质量纳米线的精确放置方法。这些研究的成功完成预计将对功能性金属氧化物材料的定向设计产生重大的积极影响，因为它将使具有高度控制和复杂性的结构，成分和界面排列的生产成为可能。这项研究意义重大，因为SLV与VLS的结合将首次实现对纳米线-模板界面的控制，本质上是“合成”具有特定化学、晶体学和间距的界面。