Ligand-induced pore regulation of Zr-MOF membrane for efficient pervaporation dehydration of dimethyl carbonate

Metal-organic framework (MOF) with rich chemical functionality and tunable pore system has shown great potential for molecular separation. Facile construction of MOF membrane with precisely tailored pore structure for achieving high-efficiency liquid separation (e.g., organic solvents dehydration) remains a challenge. Herein, we proposed a ligand modulation strategy to construct Zr-MOF membranes with tunable pore structure for dimethyl carbonate (DMC) dehydration by pervaporation. Regulating the length and bulkiness of carboxylate ligands (1,4-benzenedicarboxylic acid, H 2 BDC; 1H-pyrazole-3,5-dicarboxylic acid, H 2 PZDC; fumaric acid, H 2 FUM) was applied to prepare a series of Zr-MOF membranes. The employed linear H 2 FUM ligand with the shortest length enhanced membrane surface hydrophilicity and narrowed pore size, thus facilitating the fast and selective transport of water molecules. The resulting Zr-FUM-MOF membrane exhibited an excellent dehydration performance of 2 wt% DMC/water mixtures at 35 °C with a flux of ∼5100 g m −2  h −1 and a separation factor of ∼2030, beyond the separation performance of state-of-the-arts membranes. This work paves a facile way to manipulate pore structure of MOF membranes for molecular separation.