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

Abstract

The application discloses a synthesis method of a novel nickel-based metal organic framework material and application to methanol and ethanol oxidation. The application selects organic ligands 9,10-anthracene diacid, 2,4,6-tris(4-pyridyl)-1,3,5-triazine, nickel nitrate, and a mixed solution of a solvent system composed of deionized water, N, N-dimethylacetamide and 37% mass concentration HBF4, and obtains a porous metal organic framework material through a hydrothermal method, and the synthesized material is assembled into a three-electrode system to test electrocatalytic methanol and ethanol oxidation. The application has the advantages that the metal organic framework material has simple preparation process, high crystal purity, high yield and novel structure. The experimental test data analysis shows that the Ni-MOF material has superior electrocatalytic methanol and ethanol oxidation activity. After being compounded with acetylene black (AB), the composite material AB&Ni-MOF (1:1) has superior methanol and ethanol electro-sensing activity.

Description

TECHNICAL FIELD

[0001] The present application relates to a novel metal organic framework material (nickel-MOF) formed by taking 9,10-anthracene diacid (H2ADC) as a main ligand, 2,4,6-tris (4-pyridyl) -1,3,5-triazine (TPT) as an auxiliary ligand, and transition metal nickel as a metal center. The nickel-MOF shows excellent methanol and ethanol oxidation activity by testing the prepared catalyst electrode material, and the nickel-MOF is compounded with acetylene black to obtain a composite material AB&Ni-MOF (1:1). It is found through experiments that the composite material shows more excellent methanol and ethanol oxidation performance. BACKGROUND

[0002] Energy crisis and environmental problems In the 21st century, we humans are facing two big problems of energy crisis and environmental problems. The increasing use of fossil fuels leads to the continuous deterioration of the earth's environment, which forces people to demand a new energy system, and hydrogen energy, as a green, clean and efficient renewable energy, naturally becomes the focus of attention. In the field of catalysis, we can obtain hydrogen energy through electrocatalytic hydrogen evolution,

[0003] MOFs are metal organic framework compounds, which are connected by self-assembly of inorganic metal centers (metal ions or metal clusters) and bridged organic ligands, forming a kind of crystalline porous material with periodic network structure. At present, a metal organic framework material constructed by coordination of metal ions or metal clusters and organic ligands has extremely high specific surface area, adjustable pore size, adjustable channel size and diversity of framework composition, and is therefore considered as an extremely important electrocatalyst.

[0004] MOFs metal organic framework material is concerned because of its unique structure such as high specific surface area, adjustable pore size, adjustable channel size and diversity of framework composition, and is considered as an extremely important electrocatalyst. The application of nanomaterials prepared by using MOFs material as a template in the field of electrochemistry has been widely reported. In recent years, metal organic framework (MOFs) as a catalyst has been widely used in the field of electrocatalysis. This is because MOFs have large specific surface area and redox energy, providing abundant active sites for electrocatalysis. SUMMARY

[0005] The present application provides a synthesis method of a nickel-based metal organic framework material (Ni-MOF) formed by taking organic ligand 9,10-anthracene diacid (H2ADC) as a main ligand, 2,4,6-tris (4-pyridyl) -1,3,5-triazine (TPT) as an auxiliary ligand, and transition metal nickel as a metal center. The chemical general formula is C 14 H8N2NiO 4.33 .

[0006] The organic ligand 9,10-anthracene diacid (H2ADC), 2,4,6-tris(4-pyridyl)-1,3,5-triazine (TPT), and nickel nitrate are weighed into a glass bottle, and then a solvent, deionized water, N,N-dimethylacetamide (DMA), and HBF4 with a mass concentration of 37% are added and uniformly ultrasonically dispersed, and then green hexagonal nut block crystals (Ni-MOF) are obtained under the solvothermal reaction condition of 120-140 ℃ for 20-24 hours and at a uniform speed of 2-3 ℃ / h to room temperature, and the material is vacuum dried to prepare an electrode material for testing the methanol and ethanol oxidation performance. At the same time, equal mass (1:1) of the Ni-MOF and acetylene black (AB) synthesized by the application are placed in an agate mortar, and then ethanol is added after mechanical grinding, and the mixture is ultrasonically dispersed in an ultrasonic instrument, and then vacuum dried at 80 ℃ and ground to collect the sample, and thus the composite material AB&Ni-MOF (1:1) is obtained.

[0007] The molar ratio of the organic ligand 9,10-anthracene diacid (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 (with a mass concentration of 37%) is 5:10-15:1. The solvothermal reaction condition is 120-140 ℃, and the reaction time is 20-24 hours.

[0008] Another technical solution of the application is a crystalline material with a chemical molecular formula of C 14 H8N2NiO 4.33 The crystal of the crystalline material belongs to a hexagonal system, and the space group is P63 / mmc, and the cell parameters are: α=90°, β=90°, γ=120°, a=16.7571(2) Å, b=16.7571(2) Å, and c=15.2028(2) Å. The nickel-based metal organic framework material is used as an electrocatalyst for methanol and ethanol oxidation.

[0009] The electrocatalytic material further comprises a material obtained by compounding the crystalline material with a chemical molecular formula of C 14 H8N2NiO 4.33 and acetylene black (AB).

[0010] In some embodiments, the mass ratio of the crystalline material to acetylene black (AB) is 1:1. The room temperature in the application refers to the ambient temperature under normal pressure.

[0011] The application further provides an electrocatalyst material comprising the nickel-based metal organic framework material.

[0012] In some preferred embodiments, the material also includes acetylene black.

[0013] The crystal synthesized in this invention was structured using a small-molecule single-crystal X-ray diffractometer from Rigaku Corporation, Japan. Mo Kα rays monochromated by a graphite monochromator were used to measure diffraction intensity and cell parameters at 293 K. The collected data were empirically absorbed and corrected using scanning techniques. The results were analyzed directly using the Shelxtl-97 program and corrected using the full matrix least squares method. The resulting crystallographic data are shown in Table 1, which contains crystal parameters.

[0014] Table 1 Crystallographic Parameters

[0015] Attached Figure Description

[0016] Figure 1 : This is a packing diagram of the crystalline metal-organic framework material (Ni-MOF) synthesized in Example 4.

[0017] Figure 2 : XRD pattern of Ni-MOF prepared in Example 4.

[0018] Figure 3 : This is a scanned image (SEM) of the Ni-MOF prepared in Example 4 and the composite material AB & Ni-MOF (1:1) prepared in Example 6.

[0019] Figure 4 The table shows the CV curves of Ni-MOF prepared in Example 4 and its composite material AB&Ni-MOF (1:1) and acetylene black (AB) prepared in Example 6 in 0.1M KOH solution.

[0020] Figure 5 The table shows the CV curves 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 6 : A bar chart showing the current density 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 0.1M KOH + 1M MeOH mixed solution.

[0022] Figure 7 The table shows the stability of Ni-MOF prepared in Example 4 and its composite material AB & Ni-MOF (1:1) prepared in Example 6, as well as acetylene black (AB), in a mixed solution of 0.1M KOH + 1M MeOH.

[0023] Figure 8 The table shows the CV curves of Ni-MOF prepared in Example 4 and its composite material (AB & Ni-MOF) prepared in Example 6, as well as acetylene black (AB), in a mixed solution of 0.1M KOH + 1M EtOH.

[0024] Figure 9 : A bar chart showing the current density of Ni-MOF prepared in Example 4 and its composite material (AB & Ni-MOF) prepared in Example 6, and acetylene black (AB) in a 0.1M KOH + 1M EtOH mixed solution.

[0025] Figure 10 The table shows the stability of Ni-MOF prepared in Example 4 and its composite material (AB & Ni-MOF) prepared in Example 6, as well as acetylene black (AB), in a mixed solution of 0.1M KOH + 1M EtOH. Detailed Implementation

[0026] Example 1

[0027] Equal amounts of 0.025 mmol 9,10-anthracite (H2ADC), 0.025 mmol tpt, 0.1 mmol nickel nitrate, 2 ml deionized water, and 3 ml N,N-dimethylformamide (DMF) were weighed and added to ten 20 ml glass vials. Each reaction was sonicated for 30 min and placed in a 120 °C oven for 48 h. The temperature was then uniformly reduced to room temperature at a rate of 2-3 °C / h. All ten glass vials produced turbid liquids without crystal formation.

[0028] Example 2

[0029] Equal amounts of 0.025 mmol 9,10-anthracite (H2ADC), 0.025 mmol tpt, 0.1 mmol nickel nitrate, 2 ml deionized water, and 3 ml N,N-dimethylacetamide (DMA) were weighed and added to ten 20 ml glass vials. Each reaction was sonicated for 30 min and placed in a 120 °C oven for 48 h. The temperature was then uniformly reduced to room temperature at a rate of 2-3 °C / h. All ten glass vials produced turbid liquids without crystal formation.

[0030] Example 3

[0031] Equally weighed 0.025 mmol 9,10-anthracene diacid (H2ADC), 0.025 mmol tpt, 0.1 mmol nickel nitrate, 2 ml of deionized water, 2 ml of N, N-dimethylformamide (DMA), and then 0.05-0.55 ml of 37% HBF4 (i.e. 0.05 ml, 0.1 ml, 0.15 ml, 0.25 ml, 0.3 ml, 0.35 ml, 0.4 ml, 0.45 ml, 0.5 ml, 0.55 ml) was added to each vial, respectively, into 10 20 ml glass vials, each reaction was ultrasonically treated for 30 min and then placed in a 120°C oven for constant temperature reaction for 24 h, and then cooled to room temperature at a uniform speed of 2-3°C / h, and the 10 glass vials were all transparent clear liquid and no crystals were generated.

[0032] Example 4

[0033] Equally weighed 0.025 mmol 9,10-anthracene diacid (H2ADC), 0.025 mmol tpt, 0.1 mmol nickel nitrate, 2 ml of deionized water, 2 ml of N, N-dimethylformamide (DMA), and then 0.05-0.55 ml of 37% HBF4 (i.e. 0.05 ml, 0.1 ml, 0.15 ml, 0.25 ml, 0.3 ml, 0.35 ml, 0.4 ml, 0.45 ml, 0.5 ml, 0.55 ml) was added to each vial, respectively, into 10 20 ml glass vials, each reaction was ultrasonically treated for 30 min and then placed in a 120°C oven for constant temperature reaction for 24 h, and then cooled to room temperature at a uniform speed of 2-3°C / h, and the 10 glass vials were all transparent clear liquid and no crystals were generated. Figure 2 It can be seen that the powder diffraction peak of the prepared sample is highly consistent with the diffraction peak of the simulated Ni-MOF single crystal data, and the obtained sample is a Ni-MOF material, and the crystallographic parameters are shown in Table 1.

[0034] Example 5

[0035] The porous crystalline metal organic framework material sample (Ni-MOF) collected in Example 4 was ground uniformly in an agate mortar, 4 mg of which 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 ultrasonic treatment for 60 min, 5 μl of the dispersion was taken with a pipette and coated on the surface of a polished glassy carbon electrode, and the methanol and ethanol oxidation performance of the material was tested, and after the CV curve was scanned to be stable in 0.1M KOH solution, the methanol and ethanol oxidation CV curve was tested.

[0036] Example 6

[0037] The porous crystalline metal-organic framework material 5mg synthesized in Example 4 and conductive material acetylene black (AB) 5mg were placed in an agate mortar and ground for 15 min to obtain a composite of Ni-MOF and AB (AB&Ni-MOF). 4mg of the ground sample was weighed into a 2ml sample tube, 1.2ml of anhydrous ethanol, 0.6ml of deionized water and 0.2ml of naphthol were added, and after ultrasonic treatment for 30min, 5μl of the dispersion was drawn onto the surface of a polished glassy carbon electrode with a pipette, and the methanol and ethanol oxidation performance of the material was tested.

[0038] The Ni-MOF and AB&Ni-MOF(1:1) materials synthesized by the above method were tested for methanol and ethanol oxidation, and the experimental results showed that the Ni-MOF had good methanol and ethanol oxidation performance, and with the addition of acetylene black, the composite AB&Ni-MOF(1:1) had more excellent methanol and ethanol oxidation performance. Specifically, the oxidation activity of Ni-MOF and AB&Ni-MOF(1:1) in 0.1MKOH solution was 0.73 and 7.82mA cm -2 , which shows that the addition of acetylene black (AB) increases the conductivity of the material and accelerates the electron transport capacity, so that the material has excellent oxidation performance. After the addition of MeOH, the oxidation activity of Ni-MOF and AB&Ni-MOF was 11.02 and 39.7mA cm -2 , and the methanol oxidation performance was greatly improved. Specifically, with the addition of acetylene black (AB), the oxidation activity of the composite AB&Ni-MOF(1:1) was 3.6 times higher than that of Ni-MOF. After the addition of EtOH, the same performance trend was observed, and the oxidation activity of Ni-MOF and AB&Ni-MOF was 3.9 and 37.1mA cm -2 , specifically, with the addition of acetylene black (AB), the oxidation activity of the composite AB&Ni-MOF(1:1) was 9.5 times higher than that of Ni-MOF. This shows that the addition of acetylene black (AB) improves the conductivity of the material and accelerates the electron transport capacity, so that the oxidation activity of the material is significantly increased.

Claims

1. A nickel-based metal organic framework material characterized in that, A nickel-based metal organic framework material has a chemical formula of C 14 H8N2NiO 4.33 The crystal of the crystal material belongs to a hexagonal system, a space group is P63 / mmc, and cell parameters are: a = 90°, b = 90°, g = 120°, a = 16.7571(2) Å, b = 16.7571(2) Å, and c = 15.2028(2) Å.

2. Use of the nickel-based metal-organic framework material according to claim 1 as an electrocatalyst for the oxidation of methanol and ethanol.

3. Use of the material obtained by compounding the nickel-based metal-organic framework material according to claim 1 with acetylene black as an electrocatalyst for the oxidation of methanol and ethanol.

4. An electrocatalyst material characterized in that, including the nickel-based metal-organic framework material according to claim 1.

5. The electrocatalyst material of claim 4, wherein, The material also includes acetylene black.

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