CN110841715A - Synthesis method of MIL-68(In) MOFs hollow rod - Google Patents

Abstract

The synthesis method of the MIL-68(In) MOFs hollow rod comprises the following steps: dissolving indium nitrate tetrahydrate and terephthalic acid In an organic solvent, heating the obtained mixture In a reaction kettle for a period of time, centrifugally collecting a product, and washing to obtain an MIL-68(In) MOFs solid rod; adding the MIL-68(In) MOFs solid rod into a water solution containing tannic acid, uniformly stirring, heating the obtained mixed solution In a reaction kettle for a period of time, centrifugally collecting a product, and washing to obtain the MIL-68(In) MOFs hollow rod. According to the synthesis method of the MIL-68(In) MOFs hollow rod, tannic acid is introduced as an etching agent, the MIL-68(In) MOFs hollow rod is synthesized by a chemical etching method, the process is simple, and the cost is low; the MIL-68(In) MOFs hollow rod prepared by the method has uniform size and appearance and larger specific surface area, so that the utilization rate of the rod In catalytic chemical reaction is further improved.

Description

Synthesis of MIL-68(In)MOFs Hollow Rods

technical field

The invention relates to the preparation of metal-organic frameworks (MOFs), in particular to a method for synthesizing hollow rods of metal-organic frameworks (MIL-68 (In)).

Background technique

Metal-organic frameworks (MOFs) are a new class of organic-inorganic hybrid materials developed in the past decade. They are constructed from organic ligands and inorganic metal units, and generally have variable topological structures and unique physicochemical properties. . How to further increase the specific surface area of MOFs and further improve their utilization in catalytic chemical reactions is a hot and difficult point of current research.

SUMMARY OF THE INVENTION

On the basis of synthesizing MIL-68(In)MOFs solid rods, the invention realizes the synthesis of MIL-68(In)MOFs hollow rods by etching of tannic acid, and the details are as follows:

The synthesis method of MIL-68(In)MOFs hollow rods includes the following steps:

S1: dissolving indium nitrate tetrahydrate and terephthalic acid in an organic solvent, heating the obtained mixture in a reactor for a period of time, collecting the product by centrifugation, and washing to obtain a solid rod of MIL-68(In)MOFs;

S2: Add MIL-68(In)MOFs solid rods to the aqueous solution containing tannic acid and stir evenly, heat the resulting mixed solution in a reactor for a period of time, collect the product by centrifugation, and wash to obtain MIL-68(In) MOFs are hollow rods.

Further, the organic solvent is N,N-dimethylformamide.

Further, in the step S1, the heating temperature in the reaction kettle is 100°C, and the heating time is 6h.

Further, in the step S2, the heating temperature in the reaction kettle is 150°C, and the heating time is 1 h.

The present invention also provides the MIL-68(In)MOFs hollow rod prepared by the above synthesis method.

Compared with the prior art, the beneficial effects of the present invention:

In the method for synthesizing MIL-68(In)MOFs hollow rods of the present invention, tannic acid is introduced as an etchant, and the MIL-68(In)MOFs hollow rods are synthesized by chemical etching, the process is simple and the cost is low; The MIL-68(In)MOFs hollow rod prepared by the invention has uniform size and morphology and larger specific surface area, so that the utilization rate in catalytic chemical reaction is further improved.

Description of drawings

Fig. 1 is the XRD of the precursor prepared in the embodiment of the present invention;

Fig. 2 is the scanning electron microscope picture of the precursor prepared in the embodiment of the present invention;

Fig. 3 is the transmission electron microscope picture of the precursor prepared in the embodiment of the present invention;

Fig. 4 is the X-ray powder diffraction pattern of the MIL-68(In)MOFs hollow rod prepared in the embodiment of the present invention;

Fig. 5 is the scanning electron microscope picture of the MIL-68(In)MOFs hollow rod prepared in the embodiment of the present invention;

FIG. 6 is a transmission electron microscope image of the MIL-68(In)MOFs hollow rod prepared in the embodiment of the present invention.

Detailed ways:

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Example

Synthesis of MIL-68(In)MOFs hollow rods, including:

(1) Synthesis of MIL-68(In)MOFs Solid Rods

0.2 mmol of indium nitrate tetrahydrate and 0.18 mmol of terephthalic acid were added to a solution of 10 mL of N,N-dimethylformamide, the above mixture was heated to 100°C in a 25 mL reaction kettle and reacted for 6 h, and the product was collected by centrifugation. After washing with denatured alcohol for 4 times, solid rods of MIL-68(In)MOFs with uniform size and morphology can be obtained. Figure 1 shows the XRD of the precursor under the above experimental conditions. It can be seen from the XRD pattern that the obtained product is MIL-68(In)MOFs. Figure 2 shows the scanning electron microscope image of the precursor. It can be seen from Figure 2 that the obtained product is a rod-shaped micron material, and the particle size is relatively uniform, and the length is about 3 μm. Figure 3 shows the transmission electron microscope image of the precursor. It can be seen from Figure 3 that the obtained product is a rod-shaped micron material, the particle size is relatively uniform, and the interior is a solid structure.

(2) Synthesis of MIL-68(In)MOFs hollow rods

Add 10 mg of the above product to an aqueous solution containing 10 mg of tannic acid and stir evenly, heat the resulting mixed solution in a 25 mL reaction kettle to 150 ° C and react for 1 h, collect the product by centrifugation, and wash it with denatured alcohol for 4 times to obtain the size MIL-68(In)MOFs hollow rods with uniform morphology. Figure 4 shows the XRD of the sample after tannin etching. The XRD pattern shows that the obtained product is still MIL-68(In)MOFs. Figure 5 shows the scanning electron microscope image of the etched sample. It can be seen from Figure 5 that the obtained product is a rod-shaped micron material with a hollow structure, the particle size is relatively uniform, and the rod-shaped material is a hollow structure. Figure 6 shows a transmission electron microscope (TEM) image of the etched sample. It can be seen from Figure 6 that the obtained product is a hollow rod-like structure.

Claims (5)

1. A synthesis method of MIL-68(In) MOFs hollow rods is characterized by comprising the following steps:

   s1: dissolving indium nitrate tetrahydrate and terephthalic acid In an organic solvent, heating the obtained mixture In a reaction kettle for a period of time, centrifugally collecting a product, and washing to obtain an MIL-68(In) MOFs solid rod;

   s2: adding the MIL-68(In) MOFs solid rod into a water solution containing tannic acid, uniformly stirring, heating the obtained mixed solution In a reaction kettle for a period of time, centrifugally collecting a product, and washing to obtain the MIL-68(In) MOFs hollow rod.
2. 2. The method for synthesizing MIL-68(In) MOFs hollow rods according to claim 1, wherein the organic solvent is N, N-dimethylformamide.
3. 3. The method for synthesizing MIL-68(In) MOFs hollow rods according to claim 1, wherein the heating temperature In the reaction kettle is 100 ℃ and the heating time is 6h In step S1.
4. 4. The method for synthesizing MIL-68(In) MOFs hollow rods according to claim 1, wherein the heating temperature In the reaction kettle is 150 ℃ and the heating time is 1h In step S2.
5. 5. Hollow rods of MIL-68(In) MOFs prepared by the synthesis method of any of the preceding claims.

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