Engineering Smart Thermal Properties in Metal-Organic-Frameworks

金属有机框架中的工程智能热性能

• 批准号: 1403423
• 负责人: Peter Greaney
• 金额: $ 29.67万
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2017-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1403423&HistoricalAwards=false
• 关键词: Engineering; Smart; Thermal; Properties; Metal

CBET 1403423GreaneyThis project will determine mechanisms of heat transport in metal-organic framework materials and how the processes are tied to the materials molecular architecture. Metal-organic frameworks (MOFs) are a recently discovered class of materials that are the most porous materials known to humanity and as such they are being aggressively developed for key energy applications involving gas storage applications such as adsorption refrigeration and vehicular hydrogen storage. Surprisingly the limiting factor for MOFs in these applications is not the rate of gas permeation into the materials but the speed with which heat can be removed. MOFs are poor thermal conductors with a thermal conductivity that is similar to concrete. The knowledge gained in this project will enable the systematic design of new MOFs for these important applications with greatly improved thermal conductivity. The research will, for the first time, determine how loading MOFs with gas affects their thermal conductivity. Beyond gas storage applications, the open molecular structure of MOFs provides a number of exciting avenues for engineering exotic thermal properties. In particular this work will test mechanisms for externally tuning the thermal conductivity. The invention of the transistor in 1947 gave us ability to externally tune electrical conductivity and led to modern computing and today's information age. Finding ways to externally tune thermal conductivity could bring about a similarly dramatic change by allowing us to use heat in entirely new ways.The project has two technical objectives: (1) Advance scientific and theoretical understanding of heat transport in gas laden MOFs to enable the development of new materials for key energy applications. (2) Apply computational methods to test mechanisms for externally tuning the thermal conductivity of MOFs and determine if changes in thermal properties of MOFs could be used for chemical recognition. The research will use classical molecular dynamics (MD) simulations to determine thermal transport mechanisms across the isoreticular family of MOFs. The isoreticular series have systematically varying structures so that taken together the battery of simulations will reveal relationships between structure and thermal properties. Simulations will also determine the effects on thermal properties from deformation and interpenetration of frameworks. The research will develop a new approach for elucidating thermal transport processes from equilibrium MD simulations by computing cross-correlations in the instantaneous heat current. The mechanistic insights revealed by MD will be codified in new theoretical descriptions of thermal properties that will be applicable to other macromolecular materials.

CBET 1403423Greaney 该项目将确定金属有机框架材料中的热传输机制以及该过程如何与材料分子结构联系在一起。金属有机框架（MOF）是最近发现的一类材料，是人类已知的多孔材料，因此它们正在积极开发用于涉及气体存储应用的关键能源应用，例如吸附式制冷和车载储氢。令人惊讶的是，MOF 在这些应用中的限制因素不是气体渗透到材料中的速率，而是散热的速度。 MOF 是不良导热体，其导热率与混凝土相似。在该项目中获得的知识将能够为这些重要应用系统地设计新的 MOF，并大大提高热导率。该研究将首次确定 MOF 负载气体如何影响其导热率。除了气体储存应用之外，MOF 的开放分子结构还为设计奇异的热性能提供了许多令人兴奋的途径。特别是，这项工作将测试外部调节热导率的机制。 1947 年晶体管的发明使我们能够从外部调节电导率，并带来了现代计算和当今的信息时代。寻找外部调节热导率的方法可以让我们以全新的方式利用热量，从而带来类似的巨大变化。该项目有两个技术目标：(1) 推进对含气 MOF 热传输的科学和理论理解，以实现开发用于关键能源应用的新材料。 (2)应用计算方法来测试外部调节MOF热导率的机制，并确定MOF热性能的变化是否可用于化学识别。该研究将使用经典分子动力学 (MD) 模拟来确定等网状 MOF 家族的热传输机制。等网状系列具有系统地变化的结构，因此将一系列模拟结合起来将揭示结构和热性能之间的关系。模拟还将确定框架变形和相互渗透对热性能的影响。该研究将开发一种新方法，通过计算瞬时热流的互相关性，从平衡 MD 模拟中阐明热传输过程。 MD 揭示的机理见解将被编入新的热性能理论描述中，这些理论描述将适用于其他高分子材料。