On the water stability of ionic liquids/Cu-BTC composites: an experimental study
Ionic liquids/metal-organic framework composites are recognized as promising adsorbents for CO2 capture due to the outstanding adsorption performance, whereas their water stability, which is critical for the real application of ILs/MOF composites, has not been taken into consideration. In this work, the water stability of two ILs/Cu-BTC composites, i.e., 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]) /Cu-BTC and 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]) /Cu-BTC, were investigated. We found that the loading of ILs does not impose remarkable impacts on the crystalline structure of Cu-BTC upon water exposure; whereas the thermal stability and surface area of Cu-BTC were decreased by the incorporation of ILs, thereby leading to the reduced CO2 uptake in spite of the enhanced CO2 heat of adsorption. Furthermore, it was revealed that the decomposition of Cu-BTC occurred within the first hour of water exposure. Nevertheless, the loading of ILs retarded the decomposition of Cu-BTC according to the variations in BET surface area upon water exposure.
KeywordsMetal-organic frameworks Water exposure Ionic liquids Surface area CO2 adsorption Nanocomposite materials
We thank the support from Analytical and Testing Center of Huazhong University of Science and Technology, and the National Supercomputer Center of Shenzhen.
For research articles with several authors, a short paragraph specifying their individual contributions must be provided. The following statements should be used “Conceptualization, S. L. (Song Li); Methodology, X. X. (Xiaoxiao Xia); Software, X. X and W. L. (Wei Li); Validation, X.X.; Formal Analysis, X.X.; Investigation, X.X.; Resources, X.X.; Data Curation, X.X.; Writing-Original Draft Preparation, X.X.; Writing-Review & Editing, S.L.; Visualization, W. L. (Wei Li); Supervision, S.L.; Project Administration, S.L.; Funding Acquisition, S.L.”
This work was funded by the National Natural Science Foundation of China (NSFC) under Project No. 51606081.
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Conflict of interest
The authors declare that they have no conflicts of interest.
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