Defect and interface engineering in UiO-66-NH2/cellulose membranes for high-performance CO2 separation

A mixed-matrix membrane was developed by combining defect-engineered UiO-66-NH 2 metal-organic framework (MOF) and nanocellulose. A formic acid-modulated solvothermal method creates linker-missing defects in UiO-66-NH 2 , increasing its specific surface area from 540 to 775 m 2 g −1 . The hydroxyl/carboxyl-rich cellulose forms a robust hydrogen-bonding network with amino groups and defect sites on the MOF, suppressing interfacial defects. The optimized membrane achieves a CO 2 permeability of 303.7 Barrer with CO 2 /N 2 and CO 2 /CH 4 selectivities of 92.3 and 124.0, respectively. This enhancement arises from optimized adsorption sites in the defective MOF and superb MOF-cellulose interface capability coupled with efficient CO 2 transfer through the cellulose network. Moreover, the membrane exhibits good stability over 500 h tests, offering a promising approach to high-performance gas separation.