학술논문

Long-term entrapment and temperature-controlled-release of SF6 gas in metal–organic frameworks (MOFs)
Document Type
article
Source
Beilstein Journal of Nanotechnology, Vol 10, Iss 1, Pp 1851-1859 (2019)
Subject
benzobistriazole
gas storage
kinetic trapping
metal–organic frameworks (mofs)
sulfur hexafluoride
Technology
Chemical technology
TP1-1185
Science
Physics
QC1-999
Language
English
ISSN
2190-4286
Abstract
In this work, a metal–organic framework (MOF), namely MFU-4, which is comprised of zinc cations and benzotriazolate ligands, was used to entrap SF6 gas molecules inside its pores, and thus a new scheme for long-term leakproof storage of dangerous gasses is demonstrated. The SF6 gas was introduced into the pores at an elevated gas pressure and temperature. Upon cooling down and release of the gas pressure, we discovered that the gas was well-trapped inside the pores and did not leak out – not even after two months of exposure to air at room temperature. The material was thoroughly analyzed before and after the loading as well as after given periods of time (1, 3, 7, 14 or 60 days) after the loading. The studies included powder X-ray diffraction measurements, thermogravimetric analysis, Fourier-transform infrared spectroscopy, scanning electron microscopy, 19F nuclear magnetic resonance spectroscopy and computational simulations. In addition, the possibility to release the gas guest by applying elevated temperature, vacuum and acid-induced framework decomposition was also investigated. The controlled gas release using elevated temperature has the additional benefit that the host MOF can be reused for further gas capture cycles.