MOF Nanosheet-Based Mixed Matrix Membranes with Metal-Organic Coordination Interfacial Interaction for Gas Separation
MOF Nanosheet-Based Mixed Matrix Membranes with Metal-Organic Coordination Interfacial Interaction for Gas Separation
复制标题
基于 MOF 纳米片的混合基质膜，具有金属有机配位界面相互作用，用于气体分离。
DOI：
10.1021/acsami.0c14639
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发表时间：
2020-10-28
影响因子：
9.5
通讯作者：
Jin, Jian
中科院分区：
文献类型：
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作者：
Bi, Xiangyu;Zhang, Yong'an;Jin, Jian
在混合基质膜(MMM)中，填料与聚合物基质的界面将直接影响膜的气体分离性能。因此，在MMMS中进行合理的界面设计是重要和必要的。本工作利用金属-有机配位相互作用构建金属-有机骨架纳米片状聚酰亚胺MMM的界面，其中制备了厚度小于5 nm、横向尺寸大于5μm的超薄共苯二甲酸乙二醇酯金属-有机骨架纳米片材(CBMN)，并以羧基功能化聚酰亚胺(6FDA-Durene-DABA)为聚合物基质。由于CBMN的高长径比(>；1000)，CBMN中的Co2+与6FDA-Durene-Daba中的-COOH基团之间形成了丰富的金属-有机配位键。结果表明，6FDA-Durene-Daba/CBMN MMMS对CO2/CH4和H2/CH4气体对具有较好的分离性能，H2/CH4和CO2/CH4的选择性分别达到42.0±4.0和33.6±3.0。界面相互作用的增强使得CO2/CH4和H2/CH4气体对的综合分离性能接近或超过2008年的Robeson上限。此外，复合材料的CO_2塑化压力显著提高，达到∼20bar，是纯6FDA-Durene-DABA膜的2倍。在长期试验中，分离CO2/CH4混合气时，CO2/CH4的选择性稳定在23左右，CO2渗透率保持在400巴左右。
In the mixed matrix membrane (MMM), the interface between the filler and the polymer matrix will directly affect the gas separation performance of the membranes. Reasonable interfacial design in MMMs is thus important and necessary. In this work, metal-organic coordination interaction is used to construct the interface in metal-organic framework (MOF) nanosheet-based polyimide MMMs where ultrathin Co-benzenedicarboxylate MOF nanosheets (CBMNs) with a thickness less than 5 nm and a lateral size more than 5 μm are synthesized as fillers and a carboxyl-functionalized polyimide (6FDA-durene-DABA) is used as a polymer matrix. Because of the high aspect ratio (>1000) of CBMNs, abundant metal-organic coordination bonds are formed between Co2+ in CBMNs and the -COOH group in 6FDA-durene-DABA. As a result, the 6FDA-durene-DABA/CBMN MMMs exhibit improved separation performance for the CO2/CH4 and H2/CH4 gas pairs with H2/CH4 and CO2/CH4 selectivities up to 42.0 ± 4.0 and 33.6 ± 3.0, respectively. The enhanced interfacial interaction leads to the comprehensive separation performance of CO2/CH4 and H2/CH4 gas pairs approaching or surpassing the 2008 Robeson upper bound. In addition, the CO2 plasticization pressure of the MMMs is significantly enhanced up to ∼20 bar, which is 2 times that of the pure 6FDA-durene-DABA membrane. When separating a mixed gas of CO2/CH4, the selectivity of CO2/CH4 remains stable at around 23 and the CO2 permeability keeps around 400 barrer during the long-term test.