Preparation and Development of Metal-Isocyanide Framework Materials

在该项目的支持下，加州大学圣地亚哥分校的Joshua S. Figueroa教授和他的研究团队开发了一类新的金属/有机混合固态材料。目前，人们对开发具有先进功能和性能的固态材料非常感兴趣，这些材料可用于一系列技术和工业应用，包括化学分离、化学储存、能量收集和化学催化。在这些材料中，金属有机框架（MOFs）是一种无机/有机混合固态材料，是一种突出的材料。这样做的原因是因为mof可以用不同的结构制备，例如用材料的不同无机部分，并且相对容易调整特定应用的有机成分。虽然mof的合成和材料化学方面在过去二十年中取得了显着进步，但它们的制备遵循一个共同的范式。这涉及氧化金属中心与阴离子有机连接基团的相互作用。从基本的角度来看，这种特殊的结构限制了材料的化学和物理性质，特别是从依赖于具有高电子计数的金属中心存在的中介化学或吸附过程的角度来看。在这方面，本项目建立了一类中性连接基团，用于将富电子金属中心常规可靠地结合到网络材料中。该奖项的科学工作得到了极大的加强，旨在扩大加州大学圣地亚哥分校初级和社区学院转校生对材料科学研究的参与，并向当地圣地亚哥地区的高中生介绍材料科学研究的现代方面。技术摘要：在材料研究部固态与材料化学项目的支持下，加州大学圣地亚哥分校的Joshua S. Figueroa教授探索了以低价金属中心为次级建筑单元（SBUs）的异氰化物配位网络的合成和性能。有机异氰酸酯通过强大的西格玛给予和高效的pi-背键相互作用形成了强大的金属-配体键。这种电子二象性也被认为可以稳定低价金属中心。为了将这些离散的分子性质转移到网络材料中，研究人员利用多主题异氰化物连接剂制备具有低价过渡金属节点的多孔三维固态网络。此外，为了同时在这些材料的金属节点上赋予配位饱和，间terphenyl异氰化物配体拓扑结构是这些研究的主要特征。研究了新制备的异氰化物配位网络的基本材料性质。重点放在这些材料的化学吸收性能作为功能的低价金属中心掺入。作为该奖项的一部分，实验工作得到了一项教育计划的补充，该计划旨在早期纳入加州大学圣地亚哥分校的初级/社区学院转校生进行材料科学研究。这些努力的目标是增加更多学生参与STEM研究和高级培训。最后，为了增加参与这个项目的学生的培训经验，以增加课程的形式向当地高中推广也是这个项目的一个主要组成部分。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Non-technical AbstractWith this project, supported by the Solid State and Materials Chemistry Program in the Division of Materials Research, Professor Joshua S. Figueroa and his research team at the University of California, San Diego develop a new class of metal/organic hybrid solid-state materials. There is significant current interest in the development of solid-state materials with advanced function and properties for a range of technological and industrial applications, including chemical separations, chemical storage, energy harvesting and chemical catalysis. Among such materials, Metal-Organic Frameworks (MOFs), which are a type of hybrid inorganic/organic solid-state material, are a standout. The reason for this is because MOFs can be prepared with diverse structures, for example with different inorganic portions of the material, and it is relatively easy to tune the organic component for specific applications. While the synthetic and materials chemistry aspects of MOFs have significantly advanced over the past two decades, a common paradigm is followed for their preparation. This involves the interaction of oxidized metal centers with anionic organic linker groups. From a fundamental perspective, this particular constitution limits the chemical and physical properties of the materials, especially from the perspective of mediating chemical or adsorptive processes that rely on the presence of metal centers with high electron counts. In this respect, this project establishes a class of neutral linker groups for the routine and reliable incorporation of electron-rich metal centers into network materials. The scientific work of this award is augmented by a significant effort to broaden participation of junior- and community-college transfer student participation in materials science research at the University of California, San Diego, as well as to introduce local San Diego Area high school students to modern aspects of materials science research.Technical AbstractWith support from the Solid State and Materials Chemistry Program in the Division of Materials Research, Professor Joshua S. Figueroa of the University of California, San Diego explores the synthesis and properties of isocyanide coordination networks featuring low-valent metal centers as secondary building units (SBUs). Organoisocyanides are well established to form robust metal-ligand linkages via strong sigma-donation and highly efficient pi-backbonding interactions. This electronic duality has also been long recognized to stabilize low-valent metal centers. Seeking to transport these discrete molecular properties into a network-materials context, synthetic investigations are undertaken to prepare porous, three-dimensional solid-state networks featuring low-valent transition metal nodes using multi-topic isocyanide linkers. Furthermore, in an effort to simultaneously impart coordinative saturation on the metal nodes of these materials, the m-terphenyl isocyanide ligand topology are a predominant feature of these studies. Newly prepared isocyanide coordination networks are investigated in the context of their fundamental materials properties. An emphasis is placed on chemiabsorptive properties of these materials as function of the low-valent metal center incorporation. The experimental work undertaken as part of this award is complemented by an educational program targeting the early inclusion of junior/community college transfer students at the University of California, San Diego in materials science research. The goal of these efforts is to increase participation of a broader student demographic in STEM research and advanced training. Lastly, to augment training experiences for students working on this project, outreach to local area high schools in the form of curriculum augmentation is also a major component of the project.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.