Preparation method of a hierarchically porous metal-organic framework nanomaterial with adjustable pore size, nanomaterial obtained therefrom and its application

Abstract

The invention relates to a preparation method of a bore diameter adjustable hierarchical pore metal organic skeleton nanometer material. The preparation method comprises the following steps: synthesizing terephthalic acid with a zircon salt at the existence of a conditioning agent through a solvent thermal method to form a micropore zirconium-based metal organic skeleton; activating the microporezirconium-based metal organic skeleton with a low boiling point solvent and then drying to obtain an activated micropore zirconium-based metal organic skeleton; and dispersing the activated microporezirconium-based metal organic skeleton into 0.8 to 5.6 mol / L of monocarboxylic acid at the temperature of 25 to 180 DEG C for etching so as to obtain the hierarchical pore metal organic skeleton nanometer material. The invention also relates to the obtained bore diameter adjustable hierarchical pore metal organic skeleton nanometer material and application thereof. In short, according to the preparation method in the invention, a part of micropores is retained in the process that hierarchical pores are formed through etching of monocarboxylic acid, so that the obtained hierarchical pore metalorganic skeleton has chemical stability and heat stability similar to those of an original micropore skeleton.

Description

technical field [0001] The invention relates to the field of porous materials and enzyme immobilization, in particular to a method for preparing a multi-level porous metal-organic framework nanomaterial with adjustable pore size, the obtained nanomaterial and its application. Background technique [0002] Metal-organic frameworks (MOFs), as a porous material self-assembled from metal clusters and organic ligands, have been extensively studied and developed rapidly in recent years. Compared with traditional porous materials, MOFs have designable topology, tunable physicochemical properties, and variety of species. It has been widely used in the fields of gas adsorption and separation, catalysis, molecular sensing and drug release (Chem. Dalton Trans., 2016, 45, 18003-18017; CrystEngComm, 2015, 17, 706-718). However, it is obvious that the size of the pores and the channel environment determine the diffusion of guest molecules in MOFs, and the good diffusion of guest molecul...

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Problems solved by technology

However, these methods have relatively large defects and limitations

For example, in the ligand extension method, on the one hand, the extension of the ligand will cause the interpenetration of the pores, resulting in a decrease in porosity and specific surface area; on the other hand, the extension of the ligand will lead to structural instability, which is very unfavorable for the application of materials. It is true that some hierarchical porous metal-organic frameworks can be prepared by the template method, but in many cases the removal of the template will cause the collapse of the channels, and the presence of the template will lead to local amorphization when MOFs crystallize; while others Most preparation methods are only suitable for some MOFs with poor stability, and the prepared hierarchical porous MOFs are also limited in many fields due to poor chemical and thermal stability.

From the above research status at home and abroad, it can be seen that researchers are very enthusiastic in developing the preparation method of hierarchical pores, but the method has great limitations, and the prepared hierarchical porous MOFs have poor stability. An urgent matter to be solved, therefore, developing a simple and effective method to prepare stable hierarchical pore MOFs is a very practical and challenging work

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