RUI: New Ultrastable Crystalline Porous Materials

RUI：新型超稳定结晶多孔材料

• 批准号: 2105961
• 负责人: Xianhui Bu
• 金额: $ 39.2万
• 依托单位: California State University-Long Beach Foundation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2105961&HistoricalAwards=false
• 关键词: RUI; New; Ultrastable; Crystalline; Porous

NON-TECHNICAL SUMMARYMetal-organic frameworks are molecular-scale sieves composed of metal centers coordinated to organic ligands, which results in three-dimensional structures with uniform pore size. They can enable or improve large-scale energy, health, and defense applications such as gas storage and separation, water and other chemical decontamination, direct water harvesting and carbon dioxide capture from air, and nuclear waste treatment. However, currently few metal-organic framework materials have a suitable combination of porosity and chemical stability to meet the demands of these applications. Developing chemically stable and pore-size-tunable metal-organic frameworks is among the most important scientific challenges and is the objective of this project, which is supported by the Solid State and Materials Chemistry program in the Division of Materials Research. The project aims to impart high chemical stability by simultaneously creating highly connected structural building blocks and rigid frameworks that are not easily broken down by common molecules and molecular fragments, such as water and hydroxide ions. The pore geometry of these new materials can be tuned using different combinations structural building blocks and organic ligands. By developing these new synthesis pathways new materials with the highest chemical stability among metal-organic framework materials are created that can be used under harsh chemical conditions commonly encountered in real-world applications. In addition, this project enables a variety of research activities and provides rich training opportunities for a diverse population of undergraduate and graduate students at California State University – Long Beach.TECHNICAL SUMMARYWith this project, supported by the Solid State and Materials Chemistry program in the Division of Materials Research, Prof. Xianhui Bu and his research group develop synthetic pathways to create a family of new ultrastable and ultratunable metal-organic framework materials. The structural platform has an extraordinary flexibility in metal-ligand bond type (e.g., metal-carboxylate, metal-azolate, metal-pyridyl), which allows a high level of control over porosity, functionality, and stability within the same isoreticular series of materials. To expand the boundaries in acid-base stability of metal-organic frameworks, the researchers synthesize chromium-trimer-based frameworks with the high-connected (higher than 6) trimer building block. Only low-connected chromium metal-organic frameworks (6 or less) were known prior to this project, and the creation of high-connected framework materials in this project with mixed Cr-O and Cr-N crosslinks further increases the kinetic inertness of trivalent metal ions and also shields the metal nodes from chemical attacks by coordinating species. The researchers also systematically explore key experimental parameters such as reaction temperature, solvent type, and modulators, all of which play a far greater role for nonlabile metal ions in this project, compared to labile ions in most metal-organic frameworks. The integrated compositional and structural features to be achieved in this project increase acid-base stability simultaneously in both low- and high-pH directions. The exceptional chemical stability of these materials can enable a broad range of applications, especially those that operate under harsh chemical conditions such as nuclear waste treatment. In addition, this project enables a variety of research activities and provides rich training opportunities for a diverse population of undergraduate and graduate students at California State University – Long Beach.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.

非技术摘要 - 有机框架是由与有机配体协调的金属中心组成的分子尺度筛子，这会导致孔径均匀的三维结构。它们可以启用或改善大规模的能源，健康和防御应用，例如气体存储和分离，水和其他化学净化，直接收获水以及从空气中捕获二氧化碳以及核废料处理。但是，目前，很少有金属有机框架材料具有孔隙率和化学稳定性的合适组合，可以满足这些应用的需求。开发化学稳定和孔径可调节的金属有机框架是最重要的科学挑战之一，是该项目的目标，该项目得到了材料研究部的固态和材料化学计划的支持。该项目旨在通过类似地创建高度连接的结构构建块和刚性框架来赋予高化的化学稳定性，这些结构构建块和刚性框架不容易被普通分子和分子碎片（例如水和氢氧化物离子）分解。这些新材料的孔几何形状可以使用不同的组合构建块和有机配体来调整。通过开发这些新的合成途径，在金属有机框架材料中具有最高化学稳定性的新材料，可以在现实世界应用中通常遇到的HARMH化学条件下使用。此外，该项目可以启用各种研究活动，并为加利福尼亚州立大学的多样性人群（长滩）提供丰富的培训机会。技术摘要，该项目得到了材料研究部的固态和材料化学计划的支持，Xianhui BU教授及其研究小组及其研究小组开发了材料的合成途径，以创建一个材料的合成途径。结构平台具有金属配体键类型（例如金属 - 羧酸盐，金属锌，金属吡啶基）的非凡柔韧性，可以高度控制孔隙率，功能性和稳定性在同一同一质量系列材料中。为了扩大金属有机框架的酸碱稳定性的边界，研究人员将基于铬的框架构成了高连接（高于6）的三聚体构建块。在该项目之前，仅知道低连接的铬金属有机框架（6个或更少），并且该项目中使用混合的CR-O和CR-N交叉链接创建高连接的框架材料，进一步增加了三价金属离子的动力学惰性，并且还保护了金属节点的化学攻击物质。研究人员还系统地探索了关键的实验参数，例如反应温度，溶剂类型和调节剂，与大多数金属有机框架中的标签离子相比，这些项目在该项目中对非虚小金属离子的作用要大得多。在该项目中可以实现的综合组成和结构特征仅在低和高方向上提高了酸碱稳定性。这些材料的特殊化学稳定性可以实现广泛的应用，尤其是那些在有害化学条件（例如核废料处理）下运行的化学稳定性。此外，该项目可以启用各种研究活动，并为加利福尼亚州立大学的本科生和研究生多样性人群提供丰富的培训机会 - 长滩。该奖项反映了NSF的法定任务，并被认为值得通过基金会的知识分子优点和更广泛的影响审查标准通过评估来进行评估。