Highly CO2 Selective Metal–Organic Framework Membranes with Favorable Coulombic Effect

• Published in: Advanced functional materials Vol. 31; no. 4
• Main Authors: Chiou, Da‐Shiuan, Yu, Hyun Jung, Hung, Ting‐Hsiang, Lyu, Qiang, Chang, Chung‐Kai, Lee, Jong Suk, Lin, Li‐Chiang, Kang, Dun‐Yen
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 01.01.2021
• Subjects: Adsorbates; Carbon dioxide; CAU‐10‐H; CO 2 separation; Coulombic effect; Design factors; Gas membrane separation; Gas separation; Industrial applications; Materials science; membrane gas separation; Membranes; Metal-organic frameworks; metal–organic framework; Methane; Selectivity; Topology
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202006924

The topology and chemical functionality of metal–organic frameworks (MOFs) make them promising candidates for membrane gas separation; however, few meet the criteria for industrial applications, that is, selectivity of >30 for CO2/CH4 and CO2/N2. This paper reports on a dense CAU‐10‐H MOF membrane that is exceptionally CO2‐selective (ideal selectivity of 42 for CO2/N2 and 95 for CO2/CH4). The proposed membrane also achieves the highest CO2 permeability (approximately 500 Barrer) among existing pure MOF membranes with CO2/CH4 selectivity exceeding 30. State‐of‐the‐art atomistic simulations provide valuable insights into the outstanding separation performance of CAU‐10‐H at the molecular level. Adsorbent–adsorbate Coulombic interactions are identified as a crucial factor in the design of CO2‐selective MOF membranes. This work proposes a pure metal–organic framework (CAU‐10‐H) membrane with high selectivity (>30) for CO2/CH4. Relationships among structure, Coulombic effect, and transport property of CO2 in the channel of CAU‐10‐H are investigated, which can lead to the design of highly CO2 selective ultramicroporous materials for membrane separation.