Porous Liquid: A Stable ZIF-8 Colloid in Ionic Liquid with Permanent Porosity
Porous Liquid: A Stable ZIF-8 Colloid in Ionic Liquid with Permanent Porosity
复制标题
DOI：
10.1021/acs.langmuir.7b04212
复制
发表时间：
2018-03-27
期刊：
影响因子：
3.9
通讯作者：
Liu, Bo
中科院分区：
文献类型：
--
作者：
Liu, Shengjun;Liu, Jiandang;Liu, Bo
我们报道了通过将ZIF-8（{Zn（mim）（2）}，mim = 2-甲基咪唑）纳米晶分散在[Bpy][NTf 2]（N-丁基吡啶鎓双（三氟甲基磺酰基）酰亚胺）的离子液体（IL）中的基于金属有机框架（MOF）的多孔液体的实例。制备MOF基多孔液体的两个基本挑战，即稳定的胶体形成和孔隙率保持，已经被克服。在分散之前防止ZIF-8纳米晶体聚集对于通过增强ZIF-8与IL之间的相互作用在IL中形成稳定的ZIF-8胶体至关重要。所得ZIF-8 [Bpy][NTf 2]胶体能够稳定数月而不沉淀。[Bpy]具有较大离子尺寸的[NTf 2]不能占据ZIF-8中的孔，使ZIF-8笼为空以使客体分子能够进入。通过正电子湮没寿命谱和胶体中ZIF-8的I-2吸附验证了该多孔液体系统的孔隙率。MOF基多孔液体为液体床气体分离提供了一种新的材料平台。
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 I-2 adsorption in ZIF-8 in the colloid. MOF-based porous liquids could provide a new material platform for liquid-bed-based gas separations.