CAREER:Molecular level interrogations of metal-organic frameworks using electronic and structurally sensitive spectroscopy methods

非技术描述本项目的研究活动涉及一种名为金属-有机骨架的新兴多孔材料的研究，这种材料具有从碳封存到工业化学生产再到太阳能转换的潜在应用。虽然在开发用于这些用途的新框架方面取得了重大进展，但对这些材料如何工作的基本见解往往严重缺乏。本项目的研究活动旨在通过对这些材料应用背后的过程有一个基本的了解来满足这一需求。这项工作的结果对于促进这些材料的下一代合理设计具有更好的性能至关重要，因此对广泛的能源和环境可持续应用具有深远的影响。此外，作为整合研究和教育的更广泛使命的一部分，该项目的教育部分不仅将为纽瓦克地区的高中科学教师提供实践研究经验，而且将提供一种机制，将这些经验转化为有意义的高中科学课程，以满足该社区学生的具体需求。这一外展活动将对这些学校的学生产生很大影响，因为它针对的是教育他们的教育工作者。金属有机骨架是由有机分子连接的金属离子或团簇组成的晶体微孔网络的杂化材料。这些材料由于其固有的孔隙率和可调结构，允许带隙控制、气体/衬底选择性和其他协同特性的结合，因此具有巨大的基于吸附的功能的潜力。然而，在开发具有这些性质的新骨架方面的合成进展远远超过了在推进对其基于吸附的过程、反应机理和光活性性质的基本理解方面的进展。因此，在结构/功能关系中经常存在显著的模糊性，从而导致它们的实用性。这项研究的目的是通过在分子水平上理解金属有机骨架的行为来建立这些联系。该项目侧重于具有能源和环境可持续性影响的框架系统。这一广泛的潜在主题允许探索几种可开发的特性，从气体吸附到多相催化，再到光捕获和光催化。研究这些体系的目的是揭示与所观察到的性质相关的电子和分子水平的结构变化，并利用这些见解来帮助阐明其功能背后的机制。为了实现这些目标，一组有针对性的振动、光学和X射线光谱方法被用于这些系统的现场研究，在某些情况下是时间分辨的，以获得关于重要的主-客体相互作用和结构变化的实时信息。

Non-Technical DescriptionThe research activities in this project involve the investigation of an emerging class of porous materials called metal-organic frameworks that have potential applications ranging from carbon sequestration to industrial chemical production to solar energy conversion. While significant progress has been made in developing novel frameworks for these uses, basic insight on exactly how these materials work is often sorely lacking. The research activities in this project meet this need by targeting a fundamental understanding of the processes behind the applications of these materials. The outcome of this work is crucial for facilitating the rational design of the next generation of these materials with improved performances and, therefore, has far reaching implications for a broad range of energy and environmental sustainability applications. Furthermore, as part of a broader mission to integrate research and education, the educational component of the project will provide not only hands-on research experiences for high school science teachers in the Newark region, but a mechanism for translating those experiences into meaningful high school science curricula that meet the specific needs of the students in this community. This outreach initiative stands to have a large impact on the students in these schools since it targets the educators that teach them. Technical DescriptionMetal organic frameworks are hybrid materials that are composed of metal ions or clusters connected by organic molecules to form crystalline microporous networks. These materials have great potential for adsorption-based functions since their intrinsic porosity and tunable architecture allows bandgap manipulation, gas/substrate selectivity and the incorporation of other synergistic characteristics. Synthetic strides in developing new frameworks with these properties have, however, far outpaced the progress in advancing the fundamental understanding of their adsorption-based processes, reaction mechanisms and photoactive properties. Consequently, there are often significant ambiguities in the structure/function relationships that give rise to their utility. This research aims to make those connections by producing molecular level understanding of metal organic framework behavior. The project focuses on framework systems with energy and environmental sustainability implications. This broad underlying theme allows the exploration of several exploitable properties ranging from gas adsorption to heterogeneous catalysis to light harvesting and photocatalysis. The objectives in studying these systems are to expose pertinent electronic and molecular level structural changes associated with the observed properties and to use these insights to help elucidate the mechanisms behind their functionalities. To accomplish these goals, a targeted set of vibrational, optical, and X-ray spectroscopy methods are employed for in situ, and in some cases time-resolved, studies of these systems to garner real time information on the important host-guest interactions and structural changes.