(384e) Assigning New Functions to Zeolitic-Imidazolate Framework ZIF-8 Membranes Via Post Synthetic Modifications

Assigning new
functions to Zeolitic-imidazolate Framework ZIF-8 Membranes via Post Synthetic
Modifications

Hyuk Taek Kwon¹,
and Hae-Kwon Jeong*^1,2

¹Artie
McFerrin Department of Chemical Engineering and ²Department of Materials
Science and Engineering, Texas A&M University, College Station, TX 77843-3122

* Corresponding author: hjeong7@tamu.edu

Material properties of metal organic frameworks (MOFs) can
be fine-tuned via a couple of strategies. One is the direct construction of
MOFs with pre-designed ligands and metal ions having customized functions.¹ The other
is post synthetic treatments, for instance, ligand/metal exchange (PSE) and/or post
synthetic modification (PSM) on organic ligands enabled due to the labile
nature of MOFs.¹ The
former approach has less freedom in terms of property modification due to the
fact that the crystallization of MOFs is very specific to synthesis conditions such
as temperature, solvent properties, and precursor ratio where ligands and
synthesis solvents play a role of structure directing agents.¹ On the
other hand, the post synthetic treatments performed in rather mild conditions
can impart new functions to parent MOFs in a rather facile manner, which are
difficult obtained via a direct synthesis as proven on a series of MOFs.^1-4  Compared
with extensive PSE and PSM studies on bulk MOF powders, however, only limited
examples of the post synthetic treatments on MOF films^5,6
and membranes⁷ are
available.   

Here, we would like to present the modification of chemically
inert ZIF-8 membranes via PSM and/or subsequent PSM. The effect of newly
introduced functional groups on membrane properties such as gas separation
performance and water stability (hydrophobicity) will be systematically discussed.

References and Notes

1.         Tanabe KK, Cohen SM. Postsynthetic modification of
metal-organic frameworks-a progress report. Chemical Society Reviews. 2011;40(2):498-519.

2.         Fei H, Cahill JF, Prather KA, Cohen SM.
Tandem Postsynthetic Metal Ion and Ligand Exchange in Zeolitic Imidazolate
Frameworks. Inorganic Chemistry. 2013/04/01 2013;52(7):4011-4016.

3.         Kim M, Cahill JF, Fei H, Prather KA, Cohen
SM. Postsynthetic Ligand and Cation Exchange in Robust Metal?Organic
Frameworks. Journal of the American Chemical Society. 2012/10/31
2012;134(43):18082-18088.

4.         Liu B, Ma M, Zacher D, et al. Chemistry of
SURMOFs: Layer-Selective Installation of Functional Groups and Post-synthetic
Covalent Modification Probed by Fluorescence Microscopy. Journal of the
American Chemical Society. 2011/02/16 2011;133(6):1734-1737.

5.         Wang Z, Liu J, Arslan HK, et al.
Post-Synthetic Modification of Metal?Organic Framework Thin Films Using Click
Chemistry: The Importance of Strained C?C Triple Bonds. Langmuir. 2013/12/23
2013;29(51):15958-15964.

6.         Fei H, Pullen S, Wagner A, Ott S, Cohen SM.
Functionalization of robust Zr(iv)-based metal-organic framework films via a
postsynthetic ligand exchange. Chemical Communications. 2015;51(1):66-69.

7.         Huang A, Caro J. Covalent Post-Functionalization
of Zeolitic Imidazolate Framework ZIF-90 Membrane for Enhanced Hydrogen
Selectivity. Angewandte Chemie International Edition. 2011;50(21):4979-4982.