Facile fabrication of nanoscale hierarchical porous zeolitic imidazolate frameworks for enhanced toluene adsorption capacity

摘要

The development of a simple and facile synthesis route is a highly desirable but challenging process in the fabrication of nanoscale hierarchical porous zeolitic imidazolate frameworks(ZIFs).Herein we describe a facile method for rapidly synthesizing hierarchically porous ZIF-90 nanocrystals(particle sizes of~300 nm)using hydroxyl double salts as intermediates at room temperature.The as-synthesized ZIF-90 contained hierarchical porous structures developed using a crystalline interior and a random stack of multiple nanoparticles.Both the morphology and particle size of ZIF-90 nanocrystals could be tuned by controlling the molar ratio of ICA/Zn^(2+).Note that the as-synthesized hierarchically porous ZIF-90 nanocrystals exhibited higher thermal stability compared with the conventional ZIF-90.Because of the introduction of hierarchical porous structures,the resultant hierarchically porous ZIF-90 nanocrystals showed enhanced toluene adsorption capacity than those of conventional metal organic frameworks and zeolites.