MOF Membranes for CO2 Capture: Past, Present and Future

As the society is projected to continue relying on fossil fuels for energy needs in the next decades, the increasing level of CO2 emissions due to fossil fuel use can pose bigger threats to humans and environment, considering the associated amplified greenhouse effects. Membrane technology is a promising energy-efficient pathway to tackle the growing conundrum of CO2 emissions. Among various classes of porous materials, metal-organic frameworks (MOFs) deserve much interest regarding membrane applications due to their highly versatile structures that can be tailored for different gas separation needs. Computational modeling of MOFs for membrane-based separations can provide molecular-level information that may not be accessible via experiments and help establish the theoretical foundation for the performance trends observed in gas separation experiments. This perspective focuses on the investigation of pure MOF membranes and MOF-based composite membranes for CO2 capture applications such as post-combustion (CO2/N2) and pre-combustion CO2 separation (CO2/H2), and natural gas purification (CO2/CH4), with particular emphasis given to computational studies. We highlight the key advances and future directions in the development, modeling, and testing of early MOF membranes, ionic liquid/MOF membranes, ultrathin MOF membranes, MOF-COF (covalent organic framework) membranes, MOF glass membranes, and MOF-based mixed-matrix membranes (MMMs). Finally, an outlook on the potential opportunities and challenges associated with the computational modeling of MOF-based membranes and their use for carbon capture is provided.