CAREER: Elucidating the Synergistic Effects of Composition, Porosity and Structural Rigidity on Mechanics of Metallic Organic Frameworks

该学院早期职业发展（Career）奖将支持揭示玻璃金属有机框架（gMOFs）的组成，孔隙率，原子结构和机械行为之间基本关系的研究。gMOFs是多孔杂化材料，通常由金属离子组成，通过有机连接剂（配体）连接，形成一个巨大的增强网络。转基因mofs的一个主要优点是它们可以批量制造，具有不同的形状，适用于各种应用。该奖项将通过专注于对这些吸收材料的压缩和剪切行为的实验理解来促进科学进步，这对于它们在工业二氧化碳捕获、分离和储存应用中的使用至关重要。本文开发的技术和测试是通用的，也将增加对与gMOFs特性相似的材料的机械响应的理解。该项目还将通过研究机会和创新教材为从高中到研究生的学生提供培训。将做出特别努力，招收美国原住民学生学习STEM。该奖项的目的是了解gMOFs中的以下现象：(1)非弹性耗散过程的性质，(2)结构顺序、组成和密度的潜在不同影响，以及(3)能量松弛对适应接触载荷能力的影响。综合实验计算方法将从基于afm的压痕和划痕测试开始，以量化小尺度的压缩和剪切响应。其次，不同孔隙度的影响将通过测试与gMOFs相比具有相似孔径和孔径分布的构造硅酸盐沸石来确定。第三，为了将力学性能与原子结构的刚度联系起来，将进行结合拓扑约束理论（TCT）的MD模拟。最后，实验表征了gMOFs的整体力学行为，以关联小尺度非弹性耗散机制对宏观弹性/强度性能和非弹性行为的影响。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。

This Faculty Early Career Development (CAREER) Award will support research to uncover the fundamental relationships between composition, porosity, atomic structure, and the mechanical behavior of glassy metallic organic frameworks (gMOFs). gMOFs are porous hybrid materials, often consisting of metallic ions, connected by organic linkers (ligands), to form a vast reinforced network. A major advantage of gMOFs is that they can be made in bulk, in diverse shapes, for a variety of applications. This award will promote the progress of science by focusing on the experimental understanding of the compression and shear behaviors of these absorbent materials, which is crucial for their use in industrial CO2 capture, separation, and storage applications. The techniques and testing developed herein are generic and will also increase the understanding of mechanical responses in materials similar in characteristics to gMOFs. This project will also provide training to students from high school through graduate college via research opportunities and innovative educational material. Special efforts will be made to recruit Native American students in STEM. The objective of this award is to understand the following phenomena in gMOFs: (1) the nature of inelastic dissipation processes, (2) the underlying distinct influences of structural order, composition, and density, and (3) the influence of energy relaxation on the ability to accommodate contact loads. The integrated experimental-computational approach will start with AFM-based indentation and scratch testing to quantify compression and shear responses at small scales. Second, the effects of different porosities will be determined by testing tectosilicate zeolites that contain similar pore sizes and pore size distributions compared to the gMOFs. Third, to relate the mechanical properties to the rigidity of the atomic structure, MD simulations coupled with topological constraint theory (TCT) will be performed. Finally, bulk mechanical behavior of the gMOFs will be experimentally characterized to correlate the influence of smaller scale inelastic dissipation mechanisms on macroscale elastic/strength properties and inelastic behaviors.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.