Pore-networked gels : permanently porous ionic liquid gels with linked metal-organic polyhedra networks

Wang, Zaoming and Ozcan, Aydin and Craig, Gavin A. and Haase, Frederik and Aoyama, Takuma and Poloneeva, Daria and Horio, Keiji and Higuchi, Masakazu and Yao, Ming-Shui and Doherty, Cara M. and Maurin, Guillaume and Urayama, Kenji and Bavykina, Anastasiya and Horike, Satoshi and Gascon, Jorge and Semino, Rocio and Furukawa, Shuhei (2023) Pore-networked gels : permanently porous ionic liquid gels with linked metal-organic polyhedra networks. Journal of the American Chemical Society, 145 (26). pp. 14456-14465. ISSN 0002-7863 (https://doi.org/10.1021/jacs.3c03778)

[thumbnail of Wang-etal-JACS-2023-Pore-networked-gels]
Text. Filename: Wang_etal_JACS_2023_Pore_networked_gels.pdf
Accepted Author Manuscript
License: Strathprints license 1.0

Download (1MB)| Preview


Porous liquids (PLs) are attractive materials because of their capability to combine the intrinsic porosity of microporous solids and the processability of liquids. Most of the studies focus on the synthesis of PLs with not only high porosity but also low viscosity by considering their transportation in industrial plants. However, a gap exists between PLs and solid adsorbents for some practical cases, where the liquid characteristics and mechanical stability without leakage are simultaneously required. Here, we fill in this gap by demonstrating a new concept of pore-networked gels, in which the solvent phase is trapped by molecular networks with accessible porosity. To achieve this, we fabricate a linked metal–organic polyhedra (MOPs) gel, followed by exchanging the solvent phase with a bulky liquid such as ionic liquids (ILs); the dimethylformamide solvent trapped inside the as-synthesized gel is replaced by the target IL, 1-butyl-3-methylimidazolium tetrafluoroborate, which in turn cannot enter MOP pores due to their larger molecular size. The remaining volatile solvents in the MOP cavities can then be removed by thermal activation, endowing the obtained IL gel (Gel_IL) with accessible microporosity. The CO2 capacities of the gels are greatly enhanced compared to the neat IL. The exchange with the IL also exerts a positive influence on the final gel performances such as mechanical properties and low volatility. Besides ILs, various functional liquids are shown to be amenable to this strategy to fabricate pore-networked gels with accessible porosity, demonstrating their potential use in the field of gas adsorption or separation.