Metal-organic framework based mixed matrix hydrogel membranes for highly efficient gas separation

MOF/polymer interface in mixed-matrix membranes (MMMs) has been considered as a crucial issue for achieving highly efficient gas separation performance. In this research, aluminum fumarate framework (A520) based mixed matrix hydrogel self-supported membranes (A520-MMHMs) were prepared by a facile UV photopolymerization. The hydrophilic A520 incorporated into hydrogel polymer effectively avoided the formation of interfacial defects and improved the compatibility between MOF and hydrogel matrix. As a result, the A520-MMHM possessed enhanced CO2 permeability (∼432.87 Barrer) and CO2/CH4 selectivity (∼51.05) in comparison with pure hydrogel membrane. This performance data is very close to the updated McKeown 2019 upper bound, far exceeding the 2008 Robeson upper bound. Therefore, the design of hydrogel membrane incorporated with water-stable MOF may open up a new way for optimizing self-supported hydrogel membrane performance in gas separation.