Mixed matrix membranes (MMMs) for gas separation applications have enhanced selectivity when compared with the pure polymer matrix, but are commonly reported with low intrinsic permeability, which has major cost implications for implementation of membrane technologies in large-scale carbon capture projects. High-permeability polymers rarely generate sufficient selectivity for energy-efficient CO₂ capture. Here we report substantial selectivity enhancements within high-permeability polymers as a result of the efficient dispersion of amine-functionalized, nanosized metal–organic framework (MOF) additives. The enhancement effects under optimal mixing conditions occur with minimal loss in overall permeability. Nanosizing of the MOF enhances its dispersion within the polymer matrix to minimize non-selective microvoid formation around the particles. Amination of such MOFs increases their interaction with thepolymer matrix, resulting in a measured rigidification and enhanced selectivity of the overall composite. The optimal MOF MMM performance was verified in three different polymer systems, and also over pressure and temperature ranges suitable for carbon capture.

与纯聚合物基质相比，用于气体分离的混合基质膜（MMM）具有更高的选择性，但通常报道其固有渗透率低，这对于在大规模碳捕集项目中实施膜技术具有重大的成本影响。高渗透率的聚合物很少能产生足够的选择性，以实现高能效的CO ₂捕获。在这里，我们报告了由于胺官能化的纳米级金属-有机骨架（MOF）添加剂的有效分散，高渗透性聚合物中的选择性大大提高。在最佳混合条件下的增强效果在总磁导率损失最小的情况下发生。MOF的纳米化可增强其在聚合物基质中的分散性，以最大程度地减少颗粒周围非选择性微孔的形成。这种MOF的胺化增加了它们与聚合物基体的相互作用，从而导致了所测得的刚性和整个复合物的选择性的提高。在三种不同的聚合物系统中以及在适合碳捕集的压力和温度范围内，验证了最佳的MOF MMM性能。