Hierarchical Pore Development of ZIF-8 MOF by Simple Salt-Assisted Mechanosynthesis

Abstract

An efficient and simple mechanosynthesis was proposed to synthesize zeolitic imidazolate-based metal organic framework ZIF-8 with hierarchical superstructure. The synthesis strategy is based on a concept that only uses precursor powders for ease of handling in the solid−solid mechanochemical reaction. The solvent-free conversion of ZnO to ZIF-8 could be accelerated by an addition of zinc acetate dihydrate as both a Zn source and a catalyst. The acid dissolution of ZnO and complex forming reaction between ionized Zn and 2-methylimidazole were facilitated by the hydrated water and acetic acid generated sequentially from zinc acetate dihydrate during the reaction process. The mechanochemically synthesized ZIF-8 with trimodal hierarchical porous structure exhibited excellent adsorption rate capabilities. The large-scale rapid production and enhanced adsorption performances make this salt-assisted mechanosynthesis a very promising candidate for the industrial application and shaping of metal organic frameworks.

Vapor‐Phase Linker Exchange of the Metal–Organic Framework ZIF‐8: A Solvent‐Free Approach to Post‐synthetic Modification

“…This solution‐based approach requires large solvent volumes and the linker incorporation preference can be hard to rationalize due to solvent effects. Interestingly, several ZIF materials can be synthesized through vapor‐based and other solvent‐free methodologies . Herein, we present a novel, solvent‐free approach to post‐synthetic linker exchange in ZIF‐8 through exposure to linker vapor.…”

Generation of Hierarchical Porosity in Metal–Organic Frameworks by the Modulation of Cation Valence

“…Two predominant methods, namely direct synthesis and post treatment, have been developed to dilate the pore sizes of MOFs . For direct synthesis, larger pores are formed during the crystallization of frameworks.…”

Fabrication of Microporous Metal–Organic Frameworks in Uninterrupted Mesoporous Tunnels: Hierarchical Structure for Efficient Trypsin Immobilization and Stabilization

“…To boost the pore sizes of MOFs, two main approaches including direct synthesis and post treatment have been developed. In the case of direct synthesis, larger pores are created during the crystallization of frameworks; whereas for post treatment, microporous MOFs are first constructed followed by the generation of larger pores on crystallized structure . A classic approach of direct synthesis is the utilization of lengthened organic linkers .…”