Copper nanoparticle@metal-organic framework material and preparation method thereof

Abstract

This invention specifically designs a one-pot synthesis method for copper nanoparticles@metal-organic framework materials. The molecular formula of this metal-organic framework material is [Na 1.5 (5-SO3ipa) 0.5 ], where 5-SO3ipa is 5-sulfonic acid isophthalic acid. The structure of this three-dimensional metal-organic framework material belongs to the orthorhombic crystal system, the space group is Pnma, and the cell parameters are: a=10.6552(8), b=6.8082(5), c=15.2154(11), α=β=γ=90°. The present invention has the following beneficial effects: 1. The present invention introduces copper ions into the metal-organic framework material in a one-pot method to form copper nanoparticles@metal-organic framework material; 2. Copper nanoparticles@metal-organic framework material with full loading is synthesized by controlling the pH range.

Description

Technical Field

[0001] This invention relates to a one-pot method for preparing copper nanoparticles@metal-organic framework materials, belonging to the field of metal-organic framework material preparation. Background Technology

[0002] Metal-organic frameworks (MOFs) are porous crystalline materials that self-assemble from metal ions and organic ligands through coordination bonds. Compared with traditional porous materials, MOFs possess high specific surface area, high porosity, ordered and controllable structure, and modifiable functions, making them a focus of attention in fields such as catalysis and separation sensing.

[0003] Compared with macroscopic solid materials, copper nanomaterials have advantages such as high thermal conductivity, electrical conductivity, high catalytic activity, and superhydrophobicity. Therefore, copper nanoparticles are widely used in catalysis, sensors and other fields.

[0004] Copper nanoparticles in metal-organic frameworks (MOFs) provide more active surfaces for catalytic reactions and prevent copper nanoparticles from losing activity due to aggregation because the ordered pore structure of MOFs allows copper nanoparticles to be uniformly dispersed in the pores.

[0005] Existing reports indicate that the preparation of copper nanoparticles@metal-organic frameworks (MOFs) mostly involves introducing pre-synthesized copper nanoparticles into MOFs or other porous materials. While this method can successfully load copper nanoparticles into porous materials, it is prone to agglomeration during the loading process, affecting the material's performance. Therefore, uniformly loading nanoparticles into porous materials is crucial for improving material performance. Currently, there are no reports of obtaining copper nanoparticles@metal-organic frameworks by uniformly loading copper nanoparticles into MOF channels in a one-pot process over a wide pH range (2-14). This one-pot, stepwise control strategy holds promise for solving the agglomeration problem of copper nanoparticles in the pores. Summary of the Invention:

[0006] This invention provides a one-pot method for synthesizing copper nanoparticles@metal-organic framework materials, which can directly convert added copper ions into copper nanoparticles, thus solving the above-mentioned problems.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows:

[0008] A copper nanoparticle-metal-organic framework material, wherein the molecular formula of the metal-organic framework material is Na. 1.5 (5-SO3ipa) 0.5 It belongs to the orthorhombic crystal system, with space group Pnma and cell parameters as follows: α=β=γ=90°, Among them, 5-SO3ipa is 5-sulfonic acid isophthalic acid, and each Na + Coordination with two carboxylic acid groups and two sulfonic acid groups from different ligands forms a one-dimensional rod-shaped secondary structural unit. Each of the secondary structural units forms a three-dimensional metal-organic framework through the connection of organic ligands, and the copper nanoparticles are loaded therein to form CuNPs@MOF.

[0009] A method for preparing copper nanoparticles@metal-organic framework materials as described above includes the following steps:

[0010] Sodium 5-sulfonic isophthalic acid and copper nitrate trihydrate were added to N,N-dimethylformamide, mixed well, and the pH was adjusted to 2-14. The mixture was then sealed and subjected to a solvothermal reaction at 150-170°C to obtain the copper nanoparticles@metal-organic framework material.

[0011] As a preferred embodiment, the molar ratio of copper nitrate trihydrate to sodium 5-sulfonic acid isophthalic acid monosodium salt is 1:1 to 1:3.

[0012] In this preferred embodiment, a copper nanoparticle@metal-organic framework material with a high loading degree can be obtained. Selecting other embodiments will result in a low loading degree, or even an unloaded metal-organic framework material.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] 1. The copper nanoparticles@metal-organic framework material synthesized in this invention has a simple manufacturing process and is easy to synthesize.

[0015] 2. The present invention involves a reaction under alkaline conditions, which generates copper hydroxide from copper ions. The reaction is then carried out at 150–170°C, which causes the copper hydroxide to decompose and form copper nanoparticles.

[0016] 3. This invention obtains a fully loaded copper nanoparticle@metal-organic framework material in which copper nanoparticles are uniformly distributed in the pores by adjusting the pH value. Attached Figure Description

[0017] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0018] Figure 1 This is a schematic diagram illustrating the synthesis of copper nanoparticles@metal-organic framework materials in this invention;

[0019] Figure 2 The optical microscope image shows the morphology of copper nanoparticles loaded on metal-organic framework materials at different pH values.

[0020] Figure 3 XRD patterns of copper nanoparticles@metal-organic framework materials CuNPs@MOF(12) and copper nanoparticles (a) and metal-organic frameworks (b). Detailed Implementation

[0021] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention. These all fall within the scope of protection of the present invention.

[0022] Example 1

[0023] This experiment relates to a method for preparing MOF materials, specifically including the following steps: 0.5-0.8 mmol of 5-sulfonic acid isophthalic acid monosodium salt is added to 8-10 mL of N,N-dimethylformamide solution and mixed thoroughly, then the pH is adjusted to 12; the above solution is placed in a hydrothermal reactor and then placed in an oven, and the temperature is heated from room temperature to 150-170℃; the above temperature is maintained for 36-60 h, then the hydrothermal reactor is removed and cooled to room temperature; the solid in the hydrothermal reactor is removed, washed with N,N-dimethylformamide, and allowed to evaporate and dry naturally at room temperature to obtain a colorless block sample as the MOF material.

[0024] Example 2

[0025] This experiment relates to a method for preparing copper nanoparticles, specifically including the following steps: 0.5-0.8 mmol of copper nitrate trihydrate is added to 8-10 mL of N,N-dimethylformamide solution and mixed thoroughly, then the pH is adjusted to 12; the above solution is placed in a hydrothermal reactor and then placed in an oven, and the temperature is heated from room temperature to 150-170℃; the above temperature is maintained for 36-60 h, then the hydrothermal reactor is removed and cooled to room temperature; the solid in the hydrothermal reactor is removed, the product is washed with N,N-dimethylformamide, and after natural evaporation and drying at room temperature, a red powder sample is obtained, which is copper oxide nanoparticles (CuNPs).

[0026] Example 3

[0027] This experiment relates to a method for preparing copper nanoparticles@metal-organic framework materials, specifically including the following steps: 0.5-0.8 mmol of copper nitrate trihydrate and 0.5-0.8 mmol of sodium 5-sulfonic acid isophthalic acid were added to 8-10 ml of N,N-dimethylformamide solution and mixed evenly, and the pH value was adjusted to 2; the above solution was placed in a hydrothermal reactor and placed in an oven, and the temperature was heated from room temperature to 150-170℃; the above temperature was maintained for 36-60 h, the hydrothermal reactor was removed and cooled to room temperature; the solid in the hydrothermal reactor was taken out and washed with N,N-dimethylformamide, and dried naturally at room temperature to obtain a red block sample CuNPs@MOF(2).

[0028] Example 4

[0029] This experiment relates to a method for preparing copper nanoparticles@metal-organic framework materials, specifically including the following steps: 0.5-0.8 mmol of copper nitrate trihydrate and 0.5-0.8 mmol of sodium 5-sulfonic acid isophthalic acid were added to 8-10 mL of N,N-dimethylformamide solution and mixed evenly, and the pH value was adjusted to 4; the above solution was placed in a hydrothermal reactor and placed in an oven, and the temperature was heated from room temperature to 150-170℃; the above temperature was maintained for 36-60 h, the hydrothermal reactor was removed and cooled to room temperature; the solid in the hydrothermal reactor was taken out and washed with N,N-dimethylformamide, and dried naturally at room temperature to obtain a red block sample CuNPs@MOF(4).

[0030] Example 5

[0031] This experiment relates to a method for preparing copper nanoparticles@metal-organic framework materials, specifically including the following steps: 0.5-0.8 mmol of copper nitrate trihydrate and 0.5-0.8 mmol of sodium 5-sulfonic acid isophthalic acid were added to 8-10 ml of N,N-dimethylformamide solution and mixed evenly, and the pH was adjusted to 6; the above solution was placed in a hydrothermal reactor and placed in an oven, and the temperature was heated from room temperature to 150-170℃; the above temperature was maintained for 36-60 h, the hydrothermal reactor was removed and cooled to room temperature; the solid in the hydrothermal reactor was removed, the product was washed with N,N-dimethylformamide, and dried naturally at room temperature to obtain a red block sample CuNPs@MOF(6).

[0032] Example 6

[0033] This experiment relates to a method for preparing copper nanoparticles@metal-organic framework materials, specifically including the following steps: 0.5-0.8 mmol of copper nitrate trihydrate and 0.5-0.8 mmol of sodium 5-sulfonic acid isophthalic acid were added to 8-10 mL of N,N-dimethylformamide solution and mixed evenly, and the pH was adjusted to 8; the above solution was placed in a hydrothermal reactor and placed in an oven, and the temperature was heated from room temperature to 150-170℃; the above temperature was maintained for 36-60 h, the hydrothermal reactor was removed and cooled to room temperature; the solid in the hydrothermal reactor was removed, the product was washed with N,N-dimethylformamide, and dried naturally at room temperature to obtain a red block sample CuNPs@MOF(8).

[0034] Example 7

[0035] This experiment relates to a method for preparing copper nanoparticles@metal-organic framework materials, specifically including the following steps: 0.5-0.8 mmol of copper nitrate trihydrate and 0.5-0.8 mmol of sodium 5-sulfonyl isophthalic acid were added to 8-10 mL of N,N-dimethylformamide solution and mixed thoroughly, and the pH was adjusted to 10; the above solution was placed in a hydrothermal reactor and placed in an oven, and the temperature was heated from room temperature to 150-170℃; the above temperature was maintained for 36-60 h, the hydrothermal reactor was removed and cooled to room temperature; the solid in the hydrothermal reactor was removed, the product was washed with N,N-dimethylformamide, and dried naturally at room temperature to obtain the red sample CuNPs@MOF(10).

[0036] Example 8

[0037] This experiment relates to a method for preparing copper nanoparticles@metal-organic framework materials, specifically including the following steps: 0.5-0.8 mmol of copper nitrate trihydrate and 0.5-0.8 mmol of sodium 5-sulfonic acid isophthalic acid were added to 8 ml of N,N-dimethylformamide solution and mixed evenly, and the pH was adjusted to 14; the above solution was placed in a hydrothermal reactor and placed in an oven, and the temperature was heated from room temperature to 150-170℃; the above temperature was maintained for 36-60 h, the hydrothermal reactor was removed and cooled to room temperature; the solid in the hydrothermal reactor was taken out and washed with N,N-dimethylformamide, and dried naturally at room temperature to obtain a red block sample CuNPs@MOF(14).

[0038] Example 9

[0039] This experiment relates to a method for preparing copper nanoparticles@metal-organic framework materials, specifically including the following steps: 0.5-0.8 mmol of copper nitrate trihydrate and 0.5-0.8 mmol of sodium 5-sulfonic acid isophthalic acid were added to 8-10 mL of N,N-dimethylformamide solution and mixed evenly, and the pH was adjusted to 12; the above solution was placed in a hydrothermal reactor and placed in an oven, and the temperature was heated from room temperature to 150-170℃; the above temperature was maintained for 36-60 h, the hydrothermal reactor was removed and cooled to room temperature; the solid in the hydrothermal reactor was taken out and washed with N,N-dimethylformamide, and the product was naturally evaporated and dried at room temperature to obtain the red sample CuNPs@MOF(12).

[0040] Comparative Example 1

[0041] The only difference between this implementation scheme and Example 9 is the removal of the addition of copper nitrate trihydrate, resulting in a colorless blocky sample of the MOF without copper nanoparticles.

[0042] Comparative Example 2

[0043] The only difference between this implementation scheme and Example 9 is the removal of the addition of 5-sulfonic acid isophthalic acid monosodium salt, resulting in a red blocky sample of the copper nanoparticles.

[0044] Comparative Example 3

[0045] The only difference between this implementation scheme and Example 9 is that the solution used is changed to pH=2, resulting in a partially loaded red metal-organic framework sample with copper nanoparticles@metal-organic framework material.

[0046] Comparative Example 4

[0047] The only difference between this implementation scheme and Example 9 is that the solution used is changed to pH=4, resulting in a partially loaded red metal-organic framework sample with copper nanoparticles@metal-organic framework material.

[0048] Comparative Example 5

[0049] The only difference between this implementation scheme and Example 9 is that the solution used is changed to pH=6, resulting in a partially loaded red metal-organic framework sample with copper nanoparticles@metal-organic framework material.

[0050] Comparative Example 6

[0051] The only difference between this implementation scheme and Example 9 is that the solution used is changed to pH=8, resulting in a partially loaded red metal-organic framework sample with copper nanoparticles@metal-organic framework material.

[0052] Comparative Example 7

[0053] The only difference between this implementation scheme and Example 9 is that the solution used is changed to pH=10, resulting in a partially loaded red metal-organic framework sample with copper nanoparticles@metal-organic framework material.

[0054] Comparative Example 8

[0055] The only difference between this implementation scheme and Example 9 is that the solution used is changed to pH=14, resulting in a partially loaded red metal-organic framework sample with copper nanoparticles@metal-organic framework material.

[0056] like Figure 2 As shown, metal-organic framework materials with different copper nanoparticle loadings were obtained by changing the pH value of the hydrochloric acid or sodium hydroxide solution used. The loading level varied within the pH range of 2-12; the loading level of copper nanoparticles gradually increased with increasing pH, reaching full loading at pH 12. Within the pH range of 12-14, with increasing pH, the copper oxide nanoparticles produced in the reaction may have reacted too rapidly and could not enter the MOF channels in time, leading to a gradual decrease in the copper nanoparticle loading level.

[0057] like Figure 3 As shown in Figure a, the synthesized copper nanoparticles@metal-organic framework material was compared with the sodium-based metal-organic framework material (Example 1) and their simulated PXRD patterns. The diffraction peak positions were basically the same, proving that the three materials have the same structure.

[0058] like Figure 3 As shown in b, comparing the synthesized copper nanoparticles@metal-organic framework material with copper nanoparticles (Example 2) and their PDF cards demonstrates the presence of copper oxide in both the copper nanoparticles@metal-organic framework material and the copper nanoparticles.

[0059] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention.

Claims

1. A copper nanoparticle@metal-organic framework material, characterized in that, The molecular formula of metal-organic framework materials is [Na 1.5 (5-SO3ipa) 0.5 It belongs to the orthorhombic crystal system, with space group Pnma and cell parameters as follows: α=β=γ=90°, Among them, 5-SO3ipa is 5-sulfonic acid isophthalic acid, and each Na + Coordination with two carboxylic acid groups and two sulfonic acid groups from different ligands forms a one-dimensional rod-shaped secondary structural unit. Each of the secondary structural units forms a three-dimensional metal-organic framework through the connection of organic ligands, and the copper nanoparticles are loaded therein to form CuNPs@MOF.

2. A method for preparing copper nanoparticles@metal-organic framework material as described in claim 1, characterized in that, Includes the following steps: Sodium 5-sulfonic isophthalic acid and copper nitrate trihydrate were added to N,N-dimethylformamide, mixed well, and the pH was adjusted to 2-14. The mixture was then sealed and subjected to a solvothermal reaction at 150-170°C to obtain the copper nanoparticles@metal-organic framework material.

3. The method for preparing copper nanoparticles@metal-organic framework materials as described in claim 2, characterized in that, The molar ratio of copper nitrate trihydrate to sodium 5-sulfonic acid isophthalic acid monosodium salt is 1:1 to 1:3.

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