School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, 311 Ferst Drive, Atlanta, Georgia 30332-0100, USA.
J Am Chem Soc. 2010 Jun 2;132(21):7528-39. doi: 10.1021/ja1023699.
The very large number of distinct structures that are known for metal-organic frameworks (MOFs) and related materials presents both an opportunity and a challenge for identifying materials with useful properties for targeted applications. We show that efficient computational models can be used to evaluate large numbers of MOFs for kinetic separations of light gases based on finding materials with large differences between the diffusion coefficients of adsorbed gas species. We introduce a geometric approach that rapidly identifies the key features of a pore structure that control molecular diffusion and couple this with efficient molecular modeling calculations that predict the Henry's constant and diffusion activation energy for a range of spherical adsorbates. We demonstrate our approach for >500 MOFs and >160 silica zeolites. Our results indicate that many large pore MOFs will be of limited interest for separations based on kinetic effects, but we identify a significant number of materials that are predicted to have extraordinary properties for separation of gases such as CO(2), CH(4), and H(2).
已知的金属-有机骨架（MOFs）和相关材料的大量不同结构既为识别具有特定应用有用性质的材料提供了机会，也带来了挑战。我们表明，基于寻找吸附气体物种扩散系数之间存在较大差异的材料，可以使用高效的计算模型来评估大量 MOFs 在轻气体动力学分离中的应用。我们引入了一种几何方法，可以快速识别控制分子扩散的孔结构的关键特征，并将其与高效的分子建模计算相结合，预测一系列球形吸附剂的亨利常数和扩散活化能。我们对超过 500 个 MOFs 和超过 160 个硅沸石进行了验证。我们的结果表明，许多大孔 MOFs 在基于动力学效应的分离中可能没有什么意义，但我们确定了大量具有分离 CO(2)、CH(4)和 H(2)等气体的特殊性能的材料。
