Liu Gongping, Chernikova Valeriya, Liu Yang, Zhang Kuang, Belmabkhout Youssef, Shekhah Osama, Zhang Chen, Yi Shouliang, Eddaoudi Mohamed, Koros William J
School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, USA.
State Key Laboratory of Materials-Oriented Chemical Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials, College of Chemical Engineering, Nanjing Tech University, Nanjing, China.
Nat Mater. 2018 Mar;17(3):283-289. doi: 10.1038/s41563-017-0013-1. Epub 2018 Feb 12.
Membrane-based separations can improve energy efficiency and reduce the environmental impacts associated with traditional approaches. Nevertheless, many challenges must be overcome to design membranes that can replace conventional gas separation processes. Here, we report on the incorporation of engineered submicrometre-sized metal-organic framework (MOF) crystals into polymers to form hybrid materials that successfully translate the excellent molecular sieving properties of face-centred cubic (fcu)-MOFs into the resultant membranes. We demonstrate, simultaneously, exceptionally enhanced separation performance in hybrid membranes for two challenging and economically important applications: the removal of CO and HS from natural gas and the separation of butane isomers. Notably, the membrane molecular sieving properties demonstrate that the deliberately regulated and contracted MOF pore-aperture size can discriminate between molecular pairs. The improved performance results from precise control of the linkers delimiting the triangular window, which is the sole entrance to the fcu-MOF pore. This rational-design hybrid approach provides a general toolbox for enhancing the transport properties of advanced membranes bearing molecular sieve fillers with sub-nanometre-sized pore-apertures.
基于膜的分离技术可以提高能源效率，并减少与传统方法相关的环境影响。然而，要设计出能够替代传统气体分离工艺的膜，还必须克服许多挑战。在此，我们报告了将工程化的亚微米级金属有机框架（MOF）晶体掺入聚合物中，以形成杂化材料，成功地将面心立方（fcu）-MOF的优异分子筛分性能转化到所得的膜中。我们同时展示了杂化膜在两个具有挑战性且具有经济重要性的应用中具有异常增强的分离性能：从天然气中去除CO和H₂S以及丁烷异构体的分离。值得注意的是，膜的分子筛分性能表明，经过刻意调节和收缩的MOF孔径大小可以区分分子对。性能的提高源于对界定三角形窗口（这是fcu-MOF孔的唯一入口）的连接体的精确控制。这种合理设计的杂化方法为增强带有亚纳米级孔径分子筛填料的先进膜的传输性能提供了一个通用的工具箱。
