Abstract
Zeolitic imidazolate frameworks (ZIFs) are promising materials for gas and liquid separations due to their unique pore structures and tunable surface properties. Recent studies show that ZIF crystalline powders, especially membranes, are not stable in aqueous solutions. The present work shows the improvement of ZIF-8 crystal and membrane stability in water through utilization of a ligand exchange post-modification method which replaces methylimidazole ligands on the outer surface of ZIF-8 crystals or membranes by the more hydrophobic, bulkier 5,6-dimethylbenzimidazole. Ligand exchange modification does not change the crystal structure, morphology or gas permeance as shown ZIF-8 powder and membrane characterization experiments. The modified ZIF-8 powders and membranes retain identical morphologies and crystallinities after static and dynamic water immersion. The modified ZIF-8 membrane exhibits stable water pervaporation flux controlled by the ZIF-8 layer while the unmodified ZIF-8 membrane experiences dissolution of the ZIF-8 layer during water pervaporation. This ligand exchange strategy enables hydrostable ZIF-8 membranes for practical applications involving aqueous solutions.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1-8 |
| Number of pages | 8 |
| Journal | Journal of Membrane Science |
| Volume | 532 |
| DOIs | |
| State | Published - Jun 15 2017 |
Fingerprint
Keywords
- Improvement
- Ligand exchange
- Stability
- Zeolitic imidazolate frameworks
- ZIF-8
ASJC Scopus subject areas
- Biochemistry
- Materials Science(all)
- Physical and Theoretical Chemistry
- Filtration and Separation
Cite this
Improving hydrostability of ZIF-8 membranes via surface ligand exchange. / Zhang, Huifeng; James, Joshua; Zhao, Man; Yao, Ying; Zhang, Yushan; Zhang, Baoquan; Lin, Jerry.
In: Journal of Membrane Science, Vol. 532, 15.06.2017, p. 1-8.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Improving hydrostability of ZIF-8 membranes via surface ligand exchange
AU - Zhang, Huifeng
AU - James, Joshua
AU - Zhao, Man
AU - Yao, Ying
AU - Zhang, Yushan
AU - Zhang, Baoquan
AU - Lin, Jerry
PY - 2017/6/15
Y1 - 2017/6/15
N2 - Zeolitic imidazolate frameworks (ZIFs) are promising materials for gas and liquid separations due to their unique pore structures and tunable surface properties. Recent studies show that ZIF crystalline powders, especially membranes, are not stable in aqueous solutions. The present work shows the improvement of ZIF-8 crystal and membrane stability in water through utilization of a ligand exchange post-modification method which replaces methylimidazole ligands on the outer surface of ZIF-8 crystals or membranes by the more hydrophobic, bulkier 5,6-dimethylbenzimidazole. Ligand exchange modification does not change the crystal structure, morphology or gas permeance as shown ZIF-8 powder and membrane characterization experiments. The modified ZIF-8 powders and membranes retain identical morphologies and crystallinities after static and dynamic water immersion. The modified ZIF-8 membrane exhibits stable water pervaporation flux controlled by the ZIF-8 layer while the unmodified ZIF-8 membrane experiences dissolution of the ZIF-8 layer during water pervaporation. This ligand exchange strategy enables hydrostable ZIF-8 membranes for practical applications involving aqueous solutions.
AB - Zeolitic imidazolate frameworks (ZIFs) are promising materials for gas and liquid separations due to their unique pore structures and tunable surface properties. Recent studies show that ZIF crystalline powders, especially membranes, are not stable in aqueous solutions. The present work shows the improvement of ZIF-8 crystal and membrane stability in water through utilization of a ligand exchange post-modification method which replaces methylimidazole ligands on the outer surface of ZIF-8 crystals or membranes by the more hydrophobic, bulkier 5,6-dimethylbenzimidazole. Ligand exchange modification does not change the crystal structure, morphology or gas permeance as shown ZIF-8 powder and membrane characterization experiments. The modified ZIF-8 powders and membranes retain identical morphologies and crystallinities after static and dynamic water immersion. The modified ZIF-8 membrane exhibits stable water pervaporation flux controlled by the ZIF-8 layer while the unmodified ZIF-8 membrane experiences dissolution of the ZIF-8 layer during water pervaporation. This ligand exchange strategy enables hydrostable ZIF-8 membranes for practical applications involving aqueous solutions.
KW - Improvement
KW - Ligand exchange
KW - Stability
KW - Zeolitic imidazolate frameworks
KW - ZIF-8
UR - http://www.scopus.com/inward/record.url?scp=85014813984&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85014813984&partnerID=8YFLogxK
U2 - 10.1016/j.memsci.2017.01.065
DO - 10.1016/j.memsci.2017.01.065
M3 - Article
AN - SCOPUS:85014813984
VL - 532
SP - 1
EP - 8
JO - Jornal of Membrane Science
JF - Jornal of Membrane Science
SN - 0376-7388
ER -