Yin Zheng, Zhao Yingbo, Wan Shuang, Yang Jian, Shi Zhaolin, Peng Si-Xu, Chen Ming-Zhu, Xie Tian-Yi, Zeng Teng-Wu, Yamamuro Osamu, Nirei Masami, Akiba Hiroshi, Zhang Yue-Biao, Yu Hai-Bin, Zeng Ming-Hua
State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, P. R. China.
Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, P. R. China.
J Am Chem Soc. 2022 Jul 27;144(29):13021-13025. doi: 10.1021/jacs.2c04532. Epub 2022 Jun 24.
Metal-organic framework (MOF) glasses are a fascinating new class of materials, yet their prosperity has been impeded by the scarcity of known examples and limited vitrification methods. In the work described in this report, we applied synergistic stimuli of vapor hydration and thermal dehydration to introduce structural disorders in interpenetrated -net MOF, which facilitate the formation of stable super-cooled liquid and quenched glass. The material after stimulus has a glass transition temperature () of 560 K, far below the decomposition temperature of 695 K. When heated, the perturbed MOF enters a super-cooled liquid phase that is stable for a long period of time (>10 s), across a broad temperature range (26 K), and has a large fragility index of 83. Quenching the super-cooled liquid gives rise to porous MOF glass with maintained framework connectivity, confirmed by EXAFS and PDF analysis. This method provides a fundamentally new route to obtain glassy materials from MOFs that cannot be melted without causing decomposition.
金属有机框架（MOF）玻璃是一类引人入胜的新型材料，然而其发展受到已知实例稀缺和玻璃化方法有限的阻碍。在本报告所述的工作中，我们应用蒸汽水合和热脱水的协同刺激，在互穿网络MOF中引入结构无序，这有助于形成稳定的过冷液体和淬火玻璃。刺激后的材料玻璃化转变温度（）为560 K，远低于695 K的分解温度。加热时，受扰动的MOF进入过冷液相，该相在很宽的温度范围（26 K）内长时间稳定（>10 s），且具有83的大脆性指数。对过冷液体进行淬火可得到具有保持框架连通性的多孔MOF玻璃，这通过EXAFS和PDF分析得到证实。该方法提供了一条从MOF获得玻璃态材料的全新途径，这些MOF在不分解的情况下无法熔化。
