Synthetic Factors Affecting the Scalable Production of Zeolitic Imidazolate Frameworks

Zeolite imidazolate frameworks (ZIFs), as an important part of metal-organic frameworks (MOFs), have received great attention in many application fields, such as gas adsorption, separation, and catalysis. It was found that the performances of these applications largely depend on ZIFs' properties, such as particle size distribution, pore size, and specific surface area, which are essentially controlled by different synthetic methods. Among all the disclosed ZIF-type structures, researches on ZIF-8 are growing since it has high chemical and thermal stability and a flexible structure. Therefore, ZIF-8 was chosen as an example in this review to illustrate how synthetic factors affect the final properties of ZIF materials. We summarize the evolution process of ZIF-8 which is divided into three stages: super saturation, nucleation, and particles. Emphasis is placed on the discussion of the influences of various factors on the formation of ZIF-8. The factors are classified into several types such as various salt sources, concentration of reactants, solvents, temperature, and so on. The challenges, prospects, and outlook of ZIF-8 in the future are presented last. This perspective aims to provide necessary information for industrial synthesis of MOF and other porous materials in the future.