Despite being rarely explored in previous studies, defect tailoring and hierarchy control have been proven to be quite effective for transcending the upper bound limitation of metal-organic framework (MOF) membranes. Aiming at high-efficiency CO 2 /N 2 separation, in this study, we prepared hierarchical defect-rich UiO-66 membrane through employing hollow-structured nanocrystals during seed layer deposition and single-mode microwave heating during epitaxial growth. Obtained membrane comprised 190 nm-thick top layer and 220 nm-sized porous bottom layer; simultaneously, high missing-linker number was preserved in the framework.
Owing to superior multi-scale structure, our UiO-66 membrane achieved CO 2 /N 2 selectivity of 37.1 and CO 2 permeance of 2113 GPU, surpassing the benchmark of pure MOF membranes; additionally, the membrane exhibited remarkable n-/i-C 4 H 10 selectivity of 22.5 and n-C 4 H 10 permeance of 552 GPU. Of particular note, H-UiO-66 membrane demonstrated near 10-fold increase in n-C 4 H 10 permeance in comparison with previous literature, which was quite beneficial for enhancing its separation efficiency.
This innovative approach provides new insights into multi-structure optimization of MOF membranes towards superior separations with significant implications for environmental and industrial applications.
Yanwei Sun, Jiahui Yan, Jie Jiang, Mingming Wu, Ting Xia, Yi Liu. Hierarchical defect-rich UiO-66 membrane towards superior flue gas and butane isomer separations. Science Bulletin, 2024, 69(14): 2174-2178. https://doi.org/10.1016/j.scib.2024.05.043
Science Bulletin