熔融淬冷有机-无机杂化玻璃力学性能的化学、结构调控和预测

The discovery of fourth family of melt-quenched glass—Metal Organic Frameworks (MOF) glasses not only opens to a new field of glass science, but also lays the foundation for the application of bulk MOF materials. However, the study on the mechanical properties of MOF glasses, which is very important to application, is scarce, especially involving in the evolution and mechanism of tuning mechanical properties of MOF glass by composition and structure. In this work, basing on our previous works on the glass formation mechanism and glass forming ability in the MOF glasses, we plan to prepare several series of MOF samples with different composition and topological structure, and make corresponding bulk glasses via hot-pressing approach. Using these MOF glasses, we will explore the evolution of mechanical properties of these MOF glasses with the change of composition and structure, and focus on their indentation deformation mechanism. Furthermore, by detecting the structural evolution of the glasses using advanced characterization techniques, we will clarify the tuning mechanism of composition and topological structure on the mechanical properties of MOF glasses. Basing on the topological constraints model for predicting the hardness of oxides glasses, we plan to build a new model to predict the hardness of MOF glasses, by introducing the density factor into calculation and considering the structural features of MOF glasses. Therefore, this project will lay the foundation for the application of MOF glasses and give a new insight into the relationship between properties and structure of glass.

第四类熔融淬冷玻璃—金属有机骨架（MOF）玻璃的发现不仅开拓了玻璃研究的新领域，也为开发新型块状MOF材料奠定了基础，但对MOF玻璃应用很重要的力学性能，特别是组分、结构对其力学性能的调控规律和机理研究还很缺乏。本项目将基于前期对MOF玻璃形成机理和玻璃形成能力基础研究，通过组分和结构设计制备多个系列MOF材料，通过真空热压法制成块状玻璃，研究组分和结构对MOF玻璃的力学性能的调控规律，着重探索此类玻璃的压痕行为的变形机理，并通过先进测试手段解析系列MOF玻璃的结构演变，探索组分和结构对MOF玻璃力学性能的调控机理；基于预测氧化物玻璃硬度的拓扑限制模型，充分考虑MOF玻璃独特的结构单元和拓扑构型，将密度因素引入数学模型，开发适用于MOF玻璃硬度预测的新拓扑限制模型。该项目不仅可以为MOF玻璃的应用奠定知识基础，也可为理解玻璃结构与性能关联提供新的见解。

作为一个全新的熔融淬冷玻璃家族，金属有机骨架（MOF）玻璃展现出了许多独特的特性和性能，并表现出巨大应用前景，但是对于MOF玻璃的微观结构以及其对力学性能的影响还未明晰。本研究以系列MOF玻璃为研究对象，利用先进结构表征手段解析了MOF玻璃的精细微观结构，发现了MOF玻璃高度的短程无序结构，发现了其短程无序结构是超强玻璃形成能力和多种性能的重要起源；利用组分化学、前处理和后处理等方法调控MOF玻璃结构，实现对MOF晶体熔融和MOF玻璃形成及性能的调控；通过制备大块透明无气泡MOF玻璃，探索了MOF玻璃的压痕变形机理和抗裂纹性能，阐明了MOF玻璃微观结构影响玻璃力学性能的机制。该项目的实施为揭示MOF玻璃的微观结构及性能调控机制提供了新的见解，探明了MOF玻璃的力学特征及其与结构之间的关联，为MOF玻璃的功能化和应用开发奠定重要技术和知识基础。