We reported an example of metal–organic framework (MOF)-based porous liquid by dispersing ZIF-8 ({Zn(mim)₂}, mim = 2-methylimidazole) nanocrystallites in ionic liquid (IL) of [Bpy][NTf₂] (N-butyl pyridinium bis(trifluoromethyl sulfonyl)imide). Two essential challenges, stable colloid formation and porosity retention, have been overcome to prepare MOF-based porous liquid. Preventing ZIF-8 nanocrystals from aggregation before dispersing is vital to form a stable ZIF-8 colloid in IL via enhancing the interaction between ZIF-8 and IL. The resultant ZIF-8–[Bpy][NTf₂] colloid is able to be stable over months without precipitating. [Bpy][NTf₂] with larger ion sizes cannot occupy pores in ZIF-8, leaving the ZIF-8 cage empty for enabling access by guest molecules. The porosity of this porous liquid system was verified by positron (e⁺) annihilation lifetime spectroscopy and I₂ adsorption in ZIF-8 in the colloid. MOF-based porous liquids could provide a new material platform for liquid-bed-based gas separations.

中文翻译：

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多孔液体：离子液体中具有永久孔隙的稳定ZIF-8胶体

我们通过将ZIF-8（{Zn（mim）₂ }，mim = 2-甲基咪唑）纳米晶体分散在[Bpy] [NTf ₂ ]（N-丁基吡啶鎓双（三氟甲基磺酰基）酰亚胺）。制备基于MOF的多孔液体已克服了两个基本挑战，即稳定的胶体形成和孔隙保持率。分散前防止ZIF-8纳米晶体聚集对于通过增强ZIF-8和IL之间的相互作用在IL中形成稳定的ZIF-8胶体至关重要。生成的ZIF-8– [Bpy] [NTf ₂ ]胶体能够在数月内保持稳定而不会沉淀。[bpy] [NTf ₂具有较大离子尺寸的离子]不能占据ZIF-8中的孔，而ZIF-8笼子则空着以允许客体分子进入。通过正电子（e ⁺）lifetime没寿命光谱和胶体中ZIF-8中的I ₂吸附来验证该多孔液体系统的孔隙率。基于MOF的多孔液体可以为基于液床的气体分离提供新的材料平台。