Hybrid MOF-COF structures for advanced gas separation membranes: a short review of synthesis, performance analysis and application potential

Abstract

This review examines the application potential of hybrid MOF-COF structures in fabricating advanced membranes for gas separation. MOF-COF membranes demonstrate exceptional gas separation performance, surpassing the Robeson upper bound for several gas mixtures, including H2/CH4, CO2/CH4, CO2/N2 and O2/N2. Key findings indicate that thin-film MOF-COF membranes exhibit remarkable selectivity and permeability, with some hybrids achieving permeance values exceeding 1,000,000 GPU and ideal separation factors over 30. Additionally, mixed matrix membranes (MMMs) containing MOF-COF hybrids show potential for combining mechanical robustness with high separation efficiency, despite challenges in achieving uniform dispersion. Future research should prioritize scaling up production methods, enhancing the mechanical stability of thin films, and improving polymer-hybrid compatibility in MMMs. Experimental validation of theoretical predictions is essential to address discrepancies and unlock the full potential of these materials. MOF-COF hybrids are poised to revolutionize gas separation technologies and offer promising directions for broader applications, including catalysis and energy storage.