使用基于有效分配原子点电荷的材料选,寻找高选择性CO2/N2吸附的MOF
Emmanuel Haldoupis1, Sankar Nair, David S Sholl
1School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, 311 Ferst Drive, Atlanta, Georgia 30332-0100, USA.
Journal of the American Chemical Society
|February 15, 2012
概括
这项研究有效地模拟了许多金属有机框架 (MOF) 中的二氧化碳 (CO2) 和 (N2) 吸附. 两个MOF显示出出色的二氧化碳选择性,并且没有从烟气中捕获二氧化碳的扩散极限.
科学领域:
- 材料科学 材料科学 材料科学
- 计算化学计算化学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 静电相互作用显著影响纳米孔质材料中CO2和N2等四极分子的吸附.
- 金属有机框架 (MOF) 是气体吸附应用的有希望的材料.
研究的目的:
- 开发和应用一种高效的计算方法,用于预测大量MOF中的CO2和N2吸附率.
- 为了确定具有高CO2/N2选择性和适合CO2捕获的扩散特性的MOF.
主要方法:
- 利用适用于周期性材料的半实证电荷平衡方法来赋予原子电荷.
- 在大约500个MOF中进行了CO2和N2吸附的分子模拟.
- 对有希望的MOF候选物进行了详细的量子化学计算和分子模拟,以评估扩散和吸附等温.
主要成果:
- 在最大的MOF数据集 (约500个结构) 中模拟了CO2和N2吸附.
- 确定了两个稳定的MOF,预计具有高的CO2/N2选择性,没有扩散限制.
- 这些MOF适用于从干空气和烟气混合物中捕获二氧化碳.
结论:
- 电荷平衡方法在对气体吸附进行大规模MOF选时是有效的.
- 特定的MOF显示了选择性二氧化碳捕获的特殊潜力,解决了关键的环境挑战.
- 计算选加速了用于碳捕获技术的先进材料的发现.
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