Preparation method of nickel-based metal organic framework material and application of composite material in alcohol oxidation

Abstract

The invention discloses a synthesis method of a novel nickel-based metal organic framework material and application of the novel nickel-based metal organic framework material to methanol and ethanol oxidation. Organic ligands 9, 10-anthracenedioic acid, 2, 4, 6-tri (4-pyridyl)-1, 3, 5-triazine and nickel nitrate are selected, a solvent system is a mixed solution composed of deionized water, N, N-dimethylacetamide and HBF4 with the mass concentration of 37%, and the porous metal organic framework material is obtained through a hydrothermal method. And assembling the synthetic material into a three-electrode system for testing the electrocatalytic methanol-ethanol oxidation. The preparation method has the advantages that the metal organic framework material is simple in preparation process, high in crystal purity and high in yield; and the structure is novel. According to experimental test data analysis, the Ni-MOF material has excellent electro-catalysis methanol and ethanol oxidation activity. After being compounded with acetylene black (AB), the composite material ABamp; ni-MOF (1: 1) has more excellent methanol and ethanol electric sensing activity.

Description

Technical Field

[0001] The present invention relates to a novel metal organic framework material (nickel-MOF) formed by using 9,10-anthracene dioic acid (H2ADC) as a main ligand, 2,4,6-tris(4-pyridyl)-1,3,5-triazine (TPT) as a secondary ligand and transition metal nickel as a metal center. Ni-MOF exhibits excellent methanol and ethanol oxidation activity through the test of preparing catalyst electrode materials. Meanwhile, Ni-MOF is compounded with acetylene black to obtain a composite material AB&Ni-MOF (1:1). Experiments show that the composite material exhibits more excellent methanol and ethanol oxidation performance. Background Art

[0002] Energy crisis and environmental problems In the 21st century, we humans are facing two major challenges: energy crisis and environmental problems. The increase in the use of fossil fuels has led to the continuous deterioration of the earth's environment, which has forced people to demand new energy systems. Hydrogen energy, as a green, clean and efficient renewable energy source, has naturally become a hot topic of concern. In the field of catalysis, we can obtain hydrogen energy through electrocatalytic hydrogen evolution. MOFs are metal-organic framework compounds, which are composed of inorganic metal centers (metal ions or metal clusters) and bridging organic ligands that are interconnected through self-assembly to form a type of crystalline porous material with a periodic network structure. At present, a metal-organic framework material coordinated by metal ions or metal clusters and organic ligands has a very high specific surface area, adjustable pore size, adjustable pore size, and diverse skeleton components, and is therefore considered to be an extremely important electrocatalyst.

[0003] MOFs metal organic framework materials are considered to be an extremely important electrocatalyst and have attracted much attention due to their unique structure, such as high specific surface area, adjustable pore size, adjustable pore size, and diverse skeleton components. The application of nanomaterials prepared with MOFs materials as templates in the field of electrochemistry has been widely reported. In recent years, metal organic frameworks (MOFs) have been widely used in the field of electrocatalysis as a catalyst. This is because MOFs have a large specific surface area and redox energy, providing abundant active sites for electrocatalysis. Summary of the invention

[0004] The present invention provides a method for synthesizing a nickel-based metal organic framework material (Ni-MOF) using an organic ligand 9,10-anthracene dioic acid (H2ADC) as a main ligand, 2,4,6-tris(4-pyridyl)-1,3,5-triazine (TPT) as a secondary ligand, and transition metal nickel as a metal center. The general chemical formula is C 14 H8N2NiO 4.33 .

[0005] Weigh the organic ligand 9,10-anthracene dioic acid (H2ADC), 2,4,6-tris(4-pyridyl)-1,3,5-triazine (TPT), and nickel nitrate into a glass bottle, then add solvent deionized water, N,N-dimethylacetamide (DMA), and 37% HBF4. After ultrasonic dispersion, react for 20-24 hours under the solvent thermal reaction conditions of 120-140℃, and cool to room temperature at a uniform rate of 2~3℃ / h to obtain green hexagonal nut block crystals (Ni-MOF). The material is vacuum dried to prepare electrode materials for testing the methanol ethanol oxidation performance. At the same time, weigh the same mass (1:1) of our synthesized Ni-MOF and acetylene black (AB) and place them in an agate mortar. After mechanical grinding, add ethanol, ultrasonically disperse in an ultrasonicator, vacuum dry at 80℃ and grind, collect the sample, and obtain the composite material AB&Ni-MOF (1:1).

[0006] The molar ratio of the organic ligand 9,10-anthracene dioic acid (H2ADC), 2,4,6-tris(4-pyridyl)-1,3,5-triazine (TPT) and nickel nitrate is 1:1:3-4, and the volume ratio of the solvent deionized water, N,N-dimethylacetamide (DMA) and HBF4 (mass concentration of 37%) is 5:10-15:1. The solvent thermal reaction conditions are 120-140°C and the reaction time is 20-24 hours.

[0007] Another technical solution of the present invention is to prepare a nickel-based metal organic framework material with a chemical molecular formula of C according to the above method. 14 H8N2NiO 4.33 The crystalline material belongs to the hexagonal system, the space group is P63 / mmc, and the unit cell parameters are: α=90°, β=90°, γ=120°, a=16.7571(2)Å, b=16.7571(2)Å, c=15.2028(2)Å. The nickel-based metal organic framework material is used as an electrocatalyst in the oxidation of methanol and ethanol.

[0008] The electrocatalytic material also includes a nickel-based metal organic framework material with a chemical formula of C 14 H8N2NiO 4.33 The material is a composite of crystalline material and acetylene black (AB).

[0009] In some embodiments, the mass ratio of the crystalline material to acetylene black (AB) is 1: 1. The room temperature involved in the present invention refers to the ambient temperature under normal pressure.

[0010] The present invention also provides an electrocatalyst material, comprising the nickel-based metal organic framework material.

[0011] In some preferred embodiments, the material further includes acetylene black.

[0012] The crystal synthesized in the present invention is measured by using a small molecule single crystal X-ray diffractometer of Rigaku Co., Ltd. of Japan. The Mo Kα rays monochromatized by a graphite monochromator are used to measure the diffraction intensity and unit cell parameters at 293K. The collected data are subjected to empirical absorption correction by using a scanning technique. The obtained results are analyzed by a direct method using the Shelxtl-97 program and corrected by the full matrix least squares method. The crystallographic data are shown in Crystal Parameter Table 1.

[0013] Table 1 Crystallographic parameters BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 : Stacking diagram of the crystalline metal organic framework material (Ni-MOF) synthesized in Example 4.

[0015] Figure 2 : XRD spectrum of Ni-MOF prepared in Example 4.

[0016] Figure 3 : Scanning (SEM) images of the Ni-MOF prepared in Example 4 and the composite material AB&Ni-MOF (1:1) prepared in Example 6.

[0017] Figure 4 : CV graphs of Ni-MOF prepared in Example 4 and its composite material AB & Ni-MOF (1:1) prepared in Example 6, and acetylene black (AB) in 0.1 M KOH solution.

[0018] Figure 5 : CV graphs of Ni-MOF prepared in Example 4 and its composite material AB & Ni-MOF (1:1) prepared in Example 6, and acetylene black (AB) in a mixed solution of 0.1M KOH+1M MeOH.

[0019] Figure 6 : Current density bar chart of Ni-MOF prepared in Example 4 and its composite material AB & Ni-MOF (1:1) prepared in Example 6, and acetylene black (AB) in a mixed solution of 0.1M KOH+1M MeOH.

[0020] Figure 7 : It stability diagram of Ni-MOF prepared in Example 4 and its composite material AB & Ni-MOF (1:1) prepared in Example 6, and acetylene black (AB) in a mixed solution of 0.1M KOH+1M MeOH.

[0021] Figure 8 : CV graphs of Ni-MOF prepared in Example 4 and its composite material (AB & Ni-MOF) prepared in Example 6, and acetylene black (AB) in a mixed solution of 0.1 M KOH + 1 M EtOH.

[0022] Fig. 9 : Current density bar chart of Ni-MOF prepared in Example 4 and its composite material (AB & Ni-MOF) prepared in Example 6, and acetylene black (AB) in a mixed solution of 0.1M KOH+1M EtOH.

[0023] Fig.10 : It stability diagram of Ni-MOF prepared in Example 4 and its composite material (AB&Ni-MOF) prepared in Example 6, and acetylene black (AB) in a mixed solution of 0.1M KOH+1M EtOH. DETAILED DESCRIPTION

[0024] Example 1 0.025mmol 9,10-anthracene dioic acid (H2ADC), 0.025mmol tpt, 0.1mmol nickel nitrate, 2ml deionized water and 3ml N,N-dimethylformamide (DMF) were weighed in equal amounts and added into 10 20ml glass vials respectively. Each reaction was ultrasonicated for 30min and placed in a 120℃ oven for constant temperature reaction for 48h, and then cooled to room temperature at a constant rate of 2-3℃ / h. All 10 glass vials had turbid liquid and no crystals were produced.

[0025] Example 2 0.025mmol 9,10-anthracene dioic acid (H2ADC), 0.025mmol tpt, 0.1mmol nickel nitrate, 2ml deionized water and 3ml N,N-dimethylacetamide (DMA) were weighed in equal amounts and added into 10 20ml glass vials respectively. Each reaction was ultrasonicated for 30min and placed in a 120℃ oven for constant temperature reaction for 48h, and then cooled to room temperature at a constant rate of 2-3℃ / h. All 10 glass vials had turbid liquid and no crystals were produced.

[0026] Example 3 0.025mmol 9,10-anthracene dioic acid (H2ADC), 0.025mmol tpt, 0.1mmol nickel nitrate, 2ml deionized water, 2ml N,N-dimethylformamide (DMA) were weighed in equal amounts, and 0.05-0.55ml (i.e. 0.05ml, 0.1ml, 0.15ml, 0.25ml, 0.3ml, 0.35ml, 0.4ml, 0.45ml, 0.5ml, 0.55ml) of 37% HBF4 was added to each vial, and added to 10 20ml glass vials respectively. Each reaction was ultrasonicated for 30min and placed in a 120℃ oven for constant temperature reaction for 24h, and then cooled to room temperature at a uniform rate of 2-3℃ / h. All 10 glass vials were transparent clear liquids, and no crystals were produced.

[0027] Example 4 Weigh 0.025mmol 9,10-anthracene dioic acid (H2ADC), 0.025mmol tpt, 0.1mmol nickel nitrate, 1ml deionized water, 3ml N,N-dimethylacetamide (DMA) in equal amounts, then add 0.05-0.55ml (i.e. 0.05ml, 0.1ml, 0.15ml, 0.25ml, 0.3ml, 0.35ml, 0.4ml, 0.45ml, 0.5ml, 0.55ml) of 37% HBF4 to each vial, add them to 10 20ml glass vials respectively, ultrasonicate each reaction for 30min and place it in a 120℃ oven for constant temperature reaction for 24h, and cool it to room temperature at a uniform rate of 2-3℃ / h. Light green crystals are generated in the vials where 0.15ml and 0.2ml HBF4 are added dropwise, and 0.15ml The crystals from the vials of HBF4 were the most regular and had the highest yield. Figure 2 It can be seen that the powder diffraction peak of the prepared sample is highly consistent with the diffraction peak of Ni-MOF simulated by single crystal data. The obtained sample is Ni-MOF material, and the crystallographic parameters are shown in Table 1.

[0028] Example 5 The porous crystalline metal organic framework material sample (Ni-MOF) collected in Example 4 was evenly ground with an agate mortar, and 4 mg was weighed into a 2 ml sample tube, 1.2 ml of anhydrous ethanol, 0.6 ml of deionized water and 0.2 ml of naphthol were added. After ultrasonication for 60 min, 5 μl of the dispersion was taken with a pipette and applied to the polished glassy carbon electrode surface. The methanol-ethanol oxidation performance of the material was tested by scanning the CV curve in a 0.1 M KOH solution until it was stable, and then testing the methanol-ethanol oxidation CV curve.

[0029] Example 6 5 mg of the porous crystalline metal organic framework material synthesized in Example 4 and 5 mg of the conductive material acetylene black (AB) were placed in an agate mortar and ground for 15 minutes to obtain a composite material of Ni-MOF and AB (AB&Ni-MOF). 4 mg of the ground sample was weighed into a 2 ml sample tube, 1.2 ml of anhydrous ethanol, 0.6 ml of deionized water and 0.2 ml of naphthol were added, and after ultrasonication for 30 minutes, 5 μl of the dispersion was sucked with a pipette and applied to the polished glassy carbon electrode surface to test the material's methanol and ethanol oxidation performance.

[0030] The Ni-MOF and AB&Ni-MOF (1:1) materials synthesized by the above method were tested for methanol and ethanol oxidation. The experimental results showed that Ni-MOF had good methanol and ethanol oxidation performance, and with the addition of acetylene black, the composite material AB&Ni-MOF (1:1) had even better methanol and ethanol oxidation performance. Specifically, the oxidation activities of Ni-MOF and AB&Ni-MOF (1:1) in 0.1M KOH solution were 0.73 and 7.82 mA cm -2 This shows that the addition of acetylene black (AB) increases the conductivity of the material and accelerates the electron transfer capacity, making our material have excellent oxidation performance. When MeOH is added, the oxidation activities of Ni-MOF and AB&Ni-MOF are 11.02 and 39.7 mA cm, respectively. -2 , the methanol oxidation performance has been greatly improved. Specifically, with the addition of acetylene black (AB), the oxidation activity of the composite material AB&Ni-MOF (1:1) increased by 3.6 times compared with Ni-MOF. The same performance trend was observed after the addition of EtOH, with the oxidation activities of Ni-MOF and AB&Ni-MOF being 3.9 and 37.1 mA cm, respectively. -2 Specifically, with the addition of acetylene black (AB), the oxidation activity of the composite material AB&Ni-MOF (1:1) increased by 9.5 times compared to Ni-MOF. This shows that the addition of acetylene black (AB) improves the conductivity of the material, accelerates the electron transmission capacity, and significantly increases the oxidation activity of our material.

Claims

1. A method for preparing a nickel-based metal organic framework material, characterized in that: The steps are as follows: organic ligands 9,10-anthracene dioic acid, 2,4,6-tri(4-pyridyl)-1,3,5-triazine and nickel nitrate are added to a mixed solution of water, N,N-dimethylacetamide (DMA) and HBF4, and a preparation method for a nickel-based metal organic framework material is obtained through a solvent thermal reaction.

2. The method for preparing a nickel-based metal organic framework material according to claim 1, characterized in that: The molar ratio of 9,10-anthracene dioic acid H2ADC, 2,4,6-tris(4-pyridyl)-1,3,5-triazine and metal salt is 1:1:3-4; the volume ratio of water, N,N-dimethylacetamide (DMA) and HBF4 is 5:10-15:

1.

3. The method for preparing a nickel-based metal organic framework material according to claim 1 or 2, characterized in that: The solvent thermal reaction conditions are 120-140°C and the reaction time is 20-24 hours.

4. The nickel-based metal organic framework material prepared by the method according to any one of claims 1 to 3, characterized in that: The chemical formula of nickel-based metal organic framework materials is C 14 H8N2NiO 4.33 The crystalline material belongs to the hexagonal crystal system, the space group is P63 / mmc, and the unit cell parameters are: α=90°, β=90°, γ=120°, a=16.7571(2)Å, b=16.7571(2)Å, c=15.2028(2)Å.

5. Use of the nickel-based metal organic framework material according to claim 4 as an electrocatalyst in the oxidation of methanol and ethanol.

6. The use according to claim 4, wherein the material further comprises a nickel-based metal organic framework material having a chemical formula of C 14 H8N2NiO 4.33 The material is a composite of crystalline material and acetylene black.

7. An electrocatalyst material, characterized in that Including the nickel-based metal organic framework material as described in claim 4.

8. The electrocatalyst material according to claim 7, characterized in that The material also includes acetylene black.

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