Manipulation strategies for improving gas separation performance on metal-organic frameworks membranes

Metal-organic frameworks (MOFs) membrane is a research hotspot for gas separation due to their high variety and adjustability in structure and function. In recent years, despite some achievements gained for the supported MOF polycrystalline membranes through in-situ design and synthesis, the low gas separation performance remains the challenge for their further gas separation applications. Therefore, this review summarizes the manipulation strategies to improve the gas separation performance of MOF membranes. Particular attention is paid to aperture/cage modification, defects elimination, membranes thickness control, crystal orientation adjustment, and surface modification of support layer at the microscopic/mesoscopic level to illustrate their effect on improving MOF membrane selectivity, permeance, and long-term stability. Moreover, some possible opportunities and challenges for further development in the field of gas separation are also provided at the end of this review.