Journal
NANOMATERIALS
Volume 13, Issue 9, Pages -Publisher
MDPI
DOI: 10.3390/nano13091529
Keywords
metal-organic framework; sorption; controlled atmosphere; ATR-FTIR; in-situ; time-dependent; kinetics
Ask authors/readers for more resources
Metal-organic frameworks (MOFs) are nanostructured coordination polymers with high porosity. In this study, the sorption and desorption of n-pentane vapor by a specific MOF (Al-MOF-TCPPH2) were investigated using in-situ time-dependent attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. The sorption kinetics followed the pseudo-first-order rate law, and the desorption process was also found to be reversible. This research shows that MOFs have potential applications in the separation of light hydrocarbons and chemo-sensing.
Metal-organic frameworks (MOFs) are highly nanostructured coordination polymers that contain metal cations and organic linkers and feature very large pore volumes and surface areas. The sorption and desorption of n-pentane vapor by porphyrin aluminum metal-organic framework Al-MOF-TCPPH2 where TCPPH2 is tetrakis(4-carboxyphenyl)porphyrin linker were studied by a novel method of in-situ time-dependent attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy in a controlled atmosphere and complementary in-situ and ex-situ methods. Sorption facilely occurs in the flow of dried air, and in the obtained adsorption complex the adsorbate molecules interact with phenyl and carboxylate groups of the linker and the O-H group. Sorption kinetics follows the pseudo-first-order rate law, as confirmed by in-situ time-dependent gravimetry. Further, an ex-situ (static) sorption of n-pentane vapor results in an adsorption complex with as much as 29.1 wt.% n-pentane with the stoichiometric formula [Al-MOF-TCPPH2](2)(n-C5H12)(7) and a distinct XRD pattern. Finally, in the flow of dried air, the adsorption complex gradually desorbed n-pentane, following the pseudo-first-order rate law. The reversibility of sorption and desorption makes porphyrin aluminum MOF promising for the separation of light hydrocarbons and chemo-sensing. In-situ time-dependent ATR-FTIR spectroscopy in a controlled atmosphere, in combination with in-situ time-dependent gravimetry, is a new approach for the determination of binding sites of sorbents with adsorbate molecules, the stoichiometry of complexes, and chemical kinetics of solid-gas interactions.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available