金属有机框架的水性稳定性使用基于ReaxFF的元动力学模拟
Yongjian Yang1, Yun Kyung Shin2, Hideaki Ooe3
1Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States.
The journal of physical chemistry. B
|July 7, 2023
概括
我们开发了一个新的ReaxFF力场来模拟金属有机框架 (MOF) 与水的反应. 模拟准确地预测了MOF的稳定性,表明具有-NO2组的ZIF更稳定于水.
科学领域:
- 材料科学 材料科学 材料科学
- 计算化学的计算化学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 在潮湿的环境中应用金属有机框架 (MOFs) 时,水性稳定性至关重要.
- 使用MOF模拟水反应是具有挑战性的,因为缺乏反应力场.
研究的目的:
- 开发一个ReaxFF力场来模拟与水发生反应的热性意达框架 (ZIF).
- 通过模拟和实验研究不同MOF的水稳定性.
主要方法:
- 开发了一个ReaxFF力场,用于MOF-水相互作用.
- 进行了元动力学模拟来研究MOF水解.
- 进行了实验性水浸试验.
- 使用XRD,TG和气体吸附来描述MOF的特性.
主要成果:
- 模拟结果与实验发现非常一致,特别是在水解能量障碍方面.
- 具有开放结构和大孔的MOF具有较低的水稳定性.
- 具有 ZnN4 四面体结构的 ZIF 显示出对水攻击的抵抗力增加.
- -NO2功能组增强了ZIF的水稳定性.
结论:
- 开发的ReaxFF力场准确地预测了MOF的水性稳定性.
- 孔径大小和金属节点等结构特征影响MOF的抗水性.
- 功能组可以用于设计更强大的MOF,以适应潮湿条件.
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