Interspersed zirconium-based metal organic framework material, preparation method thereof and application of interspersed zirconium-based metal organic framework material in methane storage
The interpenetrating zirconium-based metal-organic framework material prepared by the method solves the problem of insufficient methane storage performance of existing materials, achieves efficient methane adsorption, and has good thermal and water stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-28
- Publication Date
- 2026-04-17
AI Technical Summary
Existing zirconium-based metal-organic framework materials have not yet achieved optimal performance in methane storage, particularly in terms of thermal stability and pore structure.
Using deprotonated, bent amide-functionalized dicarboxylic acid as an organic ligand, it is reacted with zirconium chloride and N,N-dimethylformamide solvents under the action of a template agent to prepare an interpenetrating zirconium-based metal-organic framework material through a solvothermal reaction. The specific steps include mixing, heating and activation treatment to form a material with a double interpenetrating structure.
The prepared material has a large specific surface area and pore volume, exhibiting excellent methane storage performance. In particular, the methane adsorption capacity increases significantly under low temperature and high pressure conditions, demonstrating good thermal and water stability.
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Figure CN121873377A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the technical field of metal-organic framework materials, specifically relating to an interpenetrating zirconium-based metal-organic framework material. Background Technology
[0002] Metal-organic frameworks (MOFs) are a novel class of solid porous materials. They are three-dimensional network structures formed by the self-assembly of metal ions or metal clusters with organic ligands through coordination bonds. MOFs exhibit a rich variety of structures and show potential applications in energy gas adsorption and storage, carbon capture and conversion, and heterogeneous catalysis, thus attracting widespread attention from researchers over the past two decades. To date, tens of thousands of MOFs have been reported, and significant progress has been made in methane storage research.
[0003] Among the large family of metal-organic framework materials, zirconium-based MOFs are undoubtedly a very important branch that has been developed in recent years. This is mainly because these materials not only have a rich variety of structural types, but also exhibit significant thermal and chemical stability, and are widely regarded by scholars as one of the most promising MOF materials for practical applications. Summary of the Invention
[0004] The purpose of this invention is to provide an interpenetrating zirconium-based metal-organic framework material, and to provide a preparation method, activation method and application of the material.
[0005] To achieve the above objectives, the molecular formula of the interpenetrating zirconium-based metal-organic framework material provided by the present invention is [Zr6(μ3-O)4(μ3-OH)4L6]; where L represents a deprotonated bent amide-functionalized dicarboxylic acid, and the bent amide-functionalized dicarboxylic acid is 4,4'-[(thiophene-2,5-dicarbonyl)bis(nitrogenyl)]bis(2-methylbenzoic acid) (TDBADC-2CH3) or 4,4'-[(thiophene-2,5-dicarbonyl)bis(nitrogenyl)]bis(2-hydroxybenzoic acid) (TDBADC-2OH).
[0006] The intercalation-type zirconium-based metal-organic framework material provided by this invention belongs to the cubic crystal system, with space group Fd-3m. When L represents deprotonated TDBADC-2CH3, it is designated as compound 1, with the molecular formula Zr6(μ3-O) )4 (μ3-OH)4(TDBADC-CH3)6, with unit cell parameters a=b=c=39.012 Å, α=β=γ=90°, and a unit cell volume of 57461.5 Å. 3 When L represents deprotonated TDBADC-2OH, it is denoted as compound 2. Since compound 2 and compound 1 have the same network structure, the unit cell parameters of compound 2 and compound 1 are the same.
[0007] The interpenetrating zirconium-based metal-organic framework material of this invention has a double interpenetrating structure. The structure contains a cage, which is a tetrahedral cage composed of four hexanuclear zirconium clusters and six deprotonated bent amide-functionalized dicarboxylic acids. Each tetrahedral cage is adjacent to four other identical tetrahedral cages, and the four tetrahedral cages are arranged in a tetrahedral configuration.
[0008] The preparation method of the above-mentioned intercalated zirconium-based metal-organic framework material is as follows: zirconium chloride, bent amide-functionalized dicarboxylic acid, N,N-dimethylformamide (DMF), and a template agent are mixed evenly, and then heated and reacted at 110-125°C for 12-48 hours under sealed conditions. After cooling to room temperature, the intercalated zirconium-based metal-organic framework material is obtained. The template agent is selected from trifluoroacetic acid or formic acid.
[0009] In the above preparation method, the preferred molar ratio of zirconium chloride to tortuous amide-functionalized dicarboxylic acid is 1:0.5 to 1.5.
[0010] In the above preparation method, the template agent for preparing compound 1 is preferably trifluoroacetic acid, the molar ratio of zirconium chloride to trifluoroacetic acid is preferably 1:25-35, and the volume ratio of DMF to trifluoroacetic acid is preferably 2.5:0.1-0.3.
[0011] In the above preparation method, the template agent for preparing compound 2 is preferably formic acid, the molar ratio of zirconium chloride to formic acid is preferably 1:110-130, and the volume ratio of DMF to formic acid is preferably 1:0.1-0.3.
[0012] The activation method of the above-mentioned interpenetrating zirconium-based metal-organic framework material is as follows: the material is first exchanged with acetone once every 20 to 40 minutes for a total of 3 to 5 times, and then exchanged with n-hexane once every 20 to 40 minutes for a total of 3 to 5 times.
[0013] The aforementioned interpenetrating zirconium-based metal-organic framework material has a large specific surface area and pore volume. This invention also provides the use of this material in the adsorption and storage of methane.
[0014] The beneficial effects of this invention are as follows:
[0015] This invention utilizes zirconium chloride as the metal source, two different bent-type amide-functionalized dicarboxylic acids as organic ligands, N,N-dimethylformamide as the solvent, and trifluoroacetic acid or formic acid as the template agent to prepare intercalated zirconium-based metal-organic framework materials via a solvothermal reaction. The nitrogen adsorption isotherm of the materials at 77 K was tested, and the results show that the materials possess a large specific surface area and pore volume. The specific surface areas of compounds 1 and 2 are 1857 m², respectively. 2 g -1 1867 m 2 g-1 The pore volumes are 0.84 cm³. 3 g -1 0.72 cm 3 g -1 It exhibits excellent performance in the application of adsorbed methane storage and has broad application prospects in the field of methane storage. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the structure and topology of the interpenetrating zirconium-based metal-organic framework material of the present invention.
[0017] Figure 2 This is a schematic diagram of the cage of the interpenetrating zirconium-based metal-organic framework material of the present invention.
[0018] Figure 3 This is a schematic diagram of the window of the interpenetrating zirconium-based metal-organic framework material of the present invention.
[0019] Figure 4 This is a powder X-ray diffraction pattern of compound 1 prepared in Example 1.
[0020] Figure 5 This is a powder X-ray diffraction pattern of compound 2 prepared in Example 2.
[0021] Figure 6 This is a thermogravimetric analysis (TGA) diagram of compound 1 prepared in Example 1.
[0022] Figure 7 This is a thermogravimetric analysis (TGA) diagram of compound 2 prepared in Example 2.
[0023] Figure 8 This is the nitrogen adsorption isotherm of compound 1 prepared in Example 1.
[0024] Figure 9 This is the nitrogen adsorption isotherm of compound 2 prepared in Example 2.
[0025] Figure 10 This is a pore size distribution diagram of compound 1 prepared in Example 1.
[0026] Figure 11 This is a pore size distribution diagram of compound 2 prepared in Example 2.
[0027] Figure 12 This is the methane adsorption isotherm of compound 1 prepared in Example 1 at 298 K.
[0028] Figure 13 This is the methane adsorption isotherm of compound 2 prepared in Example 2 at 298 K.
[0029] Figure 14This is the methane adsorption isotherm of compound 1 prepared in Example 1 at 273 K.
[0030] Figure 15 This is the methane adsorption isotherm of compound 2 prepared in Example 2 at 273 K. Detailed Implementation
[0031] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments, but the scope of protection of the present invention is not limited to these embodiments.
[0032] Example 1
[0033] Mix 10.1 mg (0.0435 mmol) ZrCl4, 20.4 mg (0.0435 mmol) TDBADC-2CH3, 2.5 mL DMF, and 100 μL (1.35 mmol) trifluoroacetic acid thoroughly, then add the mixture to a 20 mL scintillation bottle, seal the bottle, and place it in a 120℃ oven to react for 48 hours. After cooling to room temperature, the resulting colorless and transparent crystals are compound 1.
[0034] Example 2
[0035] Mix 10.1 mg (0.0435 mmol) ZrCl4, 20.6 mg (0.0435 mmol) TDBADC-2OH, 1.0 mL DMF, and 0.2 mL (5.30 mmol) formic acid thoroughly, then add the mixture to a 20 mL scintillation bottle, seal the bottle, and place it in a 120℃ oven to react for 48 hours. After cooling to room temperature, the resulting colorless and transparent crystals are compound 2.
[0036] The structures of compounds 1 and 2 were characterized by single-crystal X-ray diffraction, and both had the molecular formula [Zr6(μ3-O]). )4 [(μ3-OH)4L6], where L represents deprotonated TDBADC-2CH3 or deprotonated TDBADC-2OH. Both crystals belong to the cubic crystal system, space group Fd-3m, with the following cell parameters: Compound 1: a=b=c=41.058, α=β=γ=90°, cell volume 64500 Å. 3 Since compound 2 and compound 1 have the same network structure, their unit cell parameters are identical. In the crystal structure, the inorganic molecular building blocks are hexahedral zirconium clusters [Zr6(μ3-O)4(μ3-OH)4]. Each hexahedral zirconium cluster [Zr6(μ3-O)4(μ3-OH)4] is in a 12-linked state, meaning each metal cluster is connected to 12 deprotonated, bent amide-functionalized dicarboxylic acid ligands, ultimately forming a three-dimensional periodic network structure with a double-interpenetrating structure (see...). Figure 1Using an extended topological analysis method, the hexanuclear zirconium cluster is simplified into a cubic octahedral secondary building block. The deprotonated TDBADC-2CH3 or deprotonated TDBADC-2OH ligands can be simplified into a connecting rod, ultimately yielding a double-interpenetrating topological network, designated fcu-c, where c represents interpenetration. Within this structure, there exists a cage, a tetrahedral cage composed of four hexanuclear zirconium clusters and six deprotonated, bent amide-functionalized dicarboxylic acid ligands. The cage's size is as follows... Figure 2 As shown in the diagram. Simultaneously, this structure also contains a window, an equilateral triangular window composed of three hexanuclear zirconium clusters and three deprotonated, bent amide-functionalized dicarboxylic acid ligands, the size of which is as shown in the diagram. Figure 3 As shown.
[0037] Figure 4 The results show that the positions of the diffraction peaks in the powder X-ray diffraction pattern of compound 1 after solvent exchange are completely consistent with the positions of the diffraction peaks in the powder X-ray diffraction pattern simulated using the structural data obtained from single-crystal structure analysis. This indicates that the single-crystal structure measured by X-ray diffractometer can well describe the material structure. It also demonstrates that this invention can prepare a large number of pure-phase zirconium-based FCU-C type metal-organic framework materials. The compound structure remains intact after acetone and n-hexane exchange, indicating a pure phase. Because compound 1 and compound 2 have the same network structure, to ensure the purity of subsequent test samples, the simulated peaks of compound 2 and compound 1 obtained from single-crystal structure analysis were compared. The results show that compound 2 is a pure phase (e.g., ...). Figure 5 (As shown).
[0038] Hydrothermal stability studies were conducted on compounds 1 and 2 obtained above: the samples were immersed in water, and powder X-ray diffraction tests were performed on the immersed samples after a certain period of time. Figure 4 and Figure 5 The results show that the sample remains a pure phase after being soaked in water for 24 hours, indicating that it has good water stability; Figure 6 and 7 The thermogravimetric analysis curves show that the skeletons of compounds 1 and 2 completely collapsed after 450 °C, indicating that they have good thermal stability.
[0039] To confirm the porosity of compounds 1 and 2 obtained above, compounds 1 and 2 were activated separately. The activation method was as follows: first, acetone was used to exchange the material every 30 minutes at room temperature for a total of 3 times; then, hexane was used to exchange the material every 30 minutes for a total of 3 times. N2 adsorption isotherms of the activated compounds 1 and 2 were tested at 77 K, yielding typical "I"-type curves (see...). Figure 8 and 9This demonstrates that they are microporous materials; the BET specific surface areas of compounds 1 and 2 are 1857 m², respectively. 2 g -1 1867 m 2 g -1 The pore volumes are 0.84 cm³. 3 g -1 0.72 cm 3 g -1 (See Figure 10 and 11 ).
[0040] To evaluate the methane storage performance of compounds 1 and 2, we tested the high-pressure methane adsorption isotherms of activated compounds 1 and 2 at 298 K and 273 K (see [link to test results]). Figures 12-15 The methane adsorption capacity of compounds 1 and 2 showed a continuous increasing trend with increasing pressure. At 298 K and 65 / 80 bar, the volumetric adsorption capacity of compound 1 was 140 / 158 cm⁻¹. 3 (STP)cm -3 The volumetric working capacity is 120 / 138 cm³ (STP) cm. -3 The volumetric adsorption capacity of compound 2 was 139 / 153 cm⁻¹. 3 (STP)cm -3 The volumetric working capacity is 117 / 131 cm³. 3 (STP) cm -3 When the temperature was reduced to 273 K, the methane storage performance of both compounds was significantly improved, with compound 1 showing a volumetric adsorption capacity of 174 / 191 cm⁻¹ at 65 / 80 bar. 3 (STP) cm -3 The volume-to-work capacity reaches 145 / 162 cm³. 3 (STP)cm -3 Compound 2 exhibits a volumetric adsorption capacity of 168 / 184 cm⁻¹ at 65 / 80 bar. 3 (STP) cm -3 The volume-to-work capacity reaches 137 / 153 cm. 3 (STP)cm -3 This indicates that compounds 1 and 2 perform excellently in the field of methane storage and have good application potential.
Claims
1. An interpenetrating zirconium-based metal-organic framework material, characterized in that: The molecular formula of the material is [Zr6(μ3-O)4(μ3-OH)4L6]; where L represents a deprotonated, bent-type amide-functionalized dicarboxylic acid, and the bent-type amide-functionalized dicarboxylic acid is 4,4'-[(thiophene-2,5-dicarbonyl)bis(azodimil)]bis(2-methylbenzoic acid) or 4,4'-[(thiophene-2,5-dicarbonyl)bis(azodimil)]bis(2-hydroxybenzoic acid); The material belongs to the cubic crystal system, space group Fd-3m, with cell parameters a=b=c=38.5886 Å, α=β=γ=90°, and a cell volume of 57461.5 Å. 3 The material has a double-interpenetrating structure, which contains a cage consisting of four hexanuclear zirconium clusters and six deprotonated bent amide-functionalized dicarboxylic acids in tetrahedral form. Each tetrahedral cage is adjacent to four other identical tetrahedral cages, and the four tetrahedral cages are arranged in a tetrahedral configuration.
2. A method for preparing the interpenetrating zirconium-based metal-organic framework material according to claim 1, characterized in that: Zirconium chloride, bent amide-functionalized dicarboxylic acid, N,N-dimethylformamide, and template agent were mixed evenly and heated to 110–125 °C for 12–48 hours under sealed conditions. After cooling to room temperature, an interpenetrating zirconium-based metal-organic framework material was obtained. The bent-type amide-functionalized dicarboxylic acid is 4,4'-[(thiophene-2,5-dicarbonyl)bis(azadiyl)]bis(2-methylbenzoic acid) or 4,4'-[(thiophene-2,5-dicarbonyl)bis(azadiyl)]bis(2-hydroxybenzoic acid); The template agent is trifluoroacetic acid or formic acid.
3. The method for preparing the interpenetrating zirconium-based metal-organic framework material according to claim 2, characterized in that: The molar ratio of zirconium chloride to bent amide-functionalized dicarboxylic acid is 1:0.5 to 1.
5.
4. The method for preparing the interpenetrating zirconium-based metal-organic framework material according to claim 2, characterized in that: When the bent-type amide-functionalized dicarboxylic acid is 4,4'-[(thiophene-2,5-dicarbonyl)bis(nitrogenyl)]bis(2-methylbenzoic acid), the template agent is trifluoroacetic acid, the molar ratio of zirconium chloride to trifluoroacetic acid is 1:25-35, and the volume ratio of N,N-dimethylformamide to trifluoroacetic acid is 2.5:0.1-0.
3.
5. The method for preparing the interpenetrating zirconium-based metal-organic framework material according to claim 2, characterized in that: When the bent-type amide-functionalized dicarboxylic acid is 4,4'-[(thiophene-2,5-dicarbonyl)bis(nitrogenyl)]bis(2-hydroxybenzoic acid), the template agent is formic acid, the molar ratio of zirconium chloride to formic acid is 1:110-130, and the volume ratio of N,N-dimethylformamide to formic acid is 1:0.1-0.
3.
6. An activation method for the interpenetrating zirconium-based metal-organic framework material according to claim 1, characterized in that: The material is first exchanged with acetone every 20-40 minutes for a total of 3-5 times, and then with n-hexane every 20-40 minutes for a total of 3-5 times.
7. The use of the interpenetrating zirconium-based metal-organic framework material activated by the method of claim 6 in the adsorption and storage of methane.