pH (potential of hydrogen) responsive metal organic framework nanometer crystal, preparation method and application

Abstract

The invention discloses a pH (potential of hydrogen) responsive metal organic framework nanometer crystal, a preparation method and application. The pH responsive metal organic framework nanometer crystal comprises a metal organic framework and a pH responsive segment, wherein the pH responsive segment is graftedadhered to an organic ligand of the metal organic framework, and can be a pH responsive polymer, a chain segment containing a carboxylic group, or a chain segment containing a pyridine group. The pH responsive metal organic framework nanometer crystal has the advantages that the pH responsive segment is grafted onto the organic ligand of the metal organic framework, so that the contact angle of the metal organic framework is changed, namely that the hydrophilicity and hydrophobicity properties of the metal organic framework are changed, thereby increasing the interface activity of the pH responsive metal organic framework; the pH responsive segment has response property to the change of the pH value of the surrounding environment, the pH responsive metal organic framework has different hydrophilicity and hydrophobicity properties under different pH values, and then the pH responsive metal organic framework can be separated and recycled by adjusting the pH value.

Description

technical field [0001] The invention belongs to the field of nanomaterial preparation, and in particular relates to a pH-responsive metal-organic framework nanocrystal, a preparation method and an application. Background technique [0002] In the early 20th century, Ramsden and Pickering found that micro-nanoscale solid particles (such as silicon dioxide, iron oxide, kaolin, etc.) can form a particle film at the oil / water interface to prevent the emulsion droplets from coalescing, thereby stabilizing the emulsion. Emulsions stabilized by solid particles are called Pickering emulsions. In recent years, many researchers have conducted extensive and in-depth research on Pickering emulsions, prepared many different types of particle-stabilized emulsions, and systematically analyzed their stabilization mechanisms and influencing factors. In addition, some researchers have also done a lot of exploration on its application, especially in the fields of drug sustained release, prepa...

AI Technical Summary

Problems solved by technology

However, the addition of surfactants brings difficulties to the separation and purification of products, and high-speed stirring not only consumes huge energy, but also causes many process problems

[0005] The interface activity of MOFs prepared by the existing technology is low, and MOFs can only perform heterogeneous catalysis of oil-water-solid three-phase, and cannot be converted into a Pickering emulsion interface catalytic system, and the reaction efficiency is low

At the same time, using MOFs as catalysts, it is difficult to realize the in-situ separation, recovery and reuse of catalysts, which reduces the use efficiency of MOFs.

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