Method for rapidly synthesizing metal-organic framework material under mild condition

Abstract

The invention discloses a method for rapidly synthesizing a metal-organic framework material under mild conditions, which comprises the following steps: adding at least one metal source and at least one organic ligand into a polar organic solvent, and mixing to form a liquid reaction medium; adding a polymer additive into a liquid reaction medium to form and maintain a dynamic chemical environment for guiding the metal source and the organic ligand to be assembled orderly in the liquid reaction; and reacting the metal source with an organic ligand in the dynamic chemical environment, and crystallizing to obtain the metal-organic framework material. A brand new path is provided for green and efficient preparation of a metal-organic framework material, the tetravalent metal organic framework is synthesized under the conditions of room temperature and normal pressure, and the synthesis time is minute level.

Description

Technical Field

[0001] This invention relates to a method for synthesizing metal-organic framework materials, and particularly to a method for rapidly synthesizing metal-organic framework materials under mild conditions. Background Technology

[0002] For the past two decades, the preparation of metal-organic frameworks (MOFs) has been almost entirely monopolized by the solvothermal / hydrothermal method: metal salts and polycarboxylic acid ligands are placed in an autoclave and reacted at 80–220 °C for 6–72 h. After crystallization, the product is obtained through filtration, solvent exchange, and high-temperature vacuum activation. While this process is simple and easy to perform in the laboratory, scale-up reveals the following inherent drawbacks: energy-intensive: high reaction temperatures and long reaction times, with single-reactor batch production cycles ≥24 h; safety hazards: high pressure and polar solvents (DMF, DEF) decompose at high temperatures, producing CO, dimethylamine, formic acid, etc., which corrode equipment and limit solvent recovery. Furthermore, there is a product-competing phase: multivalent metals (especially Ti)... 4+ Zr 4+ Ce 4+ Due to its kinetic inertness, it is easy to form dense amorphous precipitates or multiple topological competing phases, requiring the addition of mineralizers (HF, HCl) or regulators (monocarboxylic acids) for crystallization, which further increases the cost of waste and equipment.

[0003] To avoid high temperature and high pressure, two new routes have emerged in the past two years that can prepare crystalline divalent and trivalent metal-organic frameworks in minutes at room temperature:

[0004] a) Dissolution-Crystallization Instantaneous Precipitation Method

[0005] Acetate M(OAc)2 (M = Cu) 2+ Zn 2+ Co 2+ Using a precursor, the product is first completely dissolved in water at room temperature and filtered, then rapidly mixed with 4,4′-oxobiphenylic acid (H2oba) dissolved in a small amount of DMF; a liquid-solid transition occurs within 0–60 s, and PXRD shows a highly crystalline product within 1 min, with a BET area comparable to that of the solvothermal sample. Compared to this invention, this method has the disadvantage of difficulty in synthesizing tetravalent metal-organic frameworks, and with increasing feed concentration, the system exhibits strong competitive reactions and phase transitions, leading to the formation of a large amount of impurity phases, resulting in low synthesis efficiency and difficulty in industrial production.

[0006] b) Electrochemical oxidation deposition method

[0007] At a constant potential of +0.75 V (vs Ag / Ag+), Fe dissolved in DMF / 2,6-dimethylpyridine was... 2+ Oxidized to Fe3+ Fe 3+ By coordinating with terephthalic acid at the electrode interface, a dense Fe-MIL-101 thin film (BET ≈ 2300 μm) can be formed on the carboxyl-modified ITO surface within 30 min. 2 g -1 The Faraday efficiency reaches as high as 96%. By adjusting the potential or ligands, different topologies such as Fe-MIL-88B-NH2 and Fe-MIL-100 can be obtained directionally, achieving "potential-phase" selectivity. Compared with this invention, this method requires strict control of the potential and electrical work input, and does not belong to the narrow sense of room temperature rapid synthesis method. Moreover, as the feed concentration increases, the nucleation and growth become unbalanced, leading to poor crystallinity of the product and easy agglomeration. At the same time, polarization and passivation of the electrode surface will occur, causing the reaction to terminate prematurely and wasting resources.

[0008] Although divalent and trivalent systems can crystallize within minutes at room temperature, Ti 4+ Zr 4+ Hf 4+ Ce 4+ High-speed room-temperature synthesis of tetravalent MOFs has not been reported to date, and the main technical barriers are as follows:

[0009] Metal-ligand bond formation kinetics are extremely slow: high charge density results in high M–O bond strength, and the ligand exchange rate is higher than that of Fe. 3+ The difference is 2-4 orders of magnitude lower, resulting in a longer nucleation induction period (12-24 h for UiO-66 at 180 °C).

[0010] Oligomeric precursors are difficult to generate at room temperature: Zr 4+ It must first be hydrolyzed to [Zr6(μ3-O)4(μ3-OH)4] dodecacarboxylic acid secondary building unit (SBU). This process has a very small equilibrium constant at 25 °C, and usually 100–150 °C is required to observe detectable amounts of hexanuclear clusters.

[0011] Competing phases and dense precipitation: When alkali is added rapidly or the concentration is increased, the system preferentially precipitates monoclinic ZrO2 or amorphous zirconium-carboxylic acid gel, rather than an open framework;

[0012] Modulator dependence: In order to suppress excessively rapid precipitation and crystallization, conventional methods require the addition of a large amount of benzoic acid / acetic acid as a "modulator". Its concentration is coupled with the reaction temperature. At room temperature, the modulator has a weak ability to compete for coordination with the carboxylic acid ligand and cannot effectively delay nucleation.

[0013] Therefore, the “room temperature to minute-level” synthesis of tetravalent metal-organic frameworks is widely recognized as the last “hard nut to crack” in MOF chemistry, and it is urgent to break through the existing thermodynamic-kinetic coupling limitations and develop new energy input or nucleation regulation modes. Summary of the Invention

[0014] To overcome the aforementioned shortcomings and deficiencies of existing technologies, the present invention aims to provide a method for the rapid synthesis of metal-organic framework materials under mild conditions. The reaction process does not rely on traditional thermodynamic driving forces, but rather uses an "entropy-space synergistic regulation" mechanism as its underlying logic, providing a new path for the green and efficient preparation of metal-organic framework materials. In particular, it breaks through the thermodynamic-kinetic coupling limitation in existing tetravalent metal-organic framework synthesis methods, realizing the synthesis of tetravalent metal-organic frameworks under room temperature and atmospheric pressure conditions, with a synthesis time on the order of minutes.

[0015] The objective of this invention is achieved through the following technical solution:

[0016] This invention provides a method for rapidly synthesizing metal-organic framework materials under mild conditions, comprising the following steps:

[0017] At least one metal source and at least one organic ligand are added to a polar organic solvent and mixed to form a liquid reaction medium;

[0018] A polymeric auxiliary agent is added to the liquid reaction medium to form and maintain a dynamic chemical environment that guides the orderly assembly of the metal source and the organic ligand in the liquid reaction, so that the metal source and the organic ligand react and crystallize to obtain a metal-organic framework material. The formation of the dynamic chemical environment is as follows: the polymeric auxiliary agent induces the generation of transient ordered microregions in a polar organic solvent, forming a local entropy increase effect and a spatial confinement environment, so that the metal source and the organic ligand undergo directional cooperative self-assembly.

[0019] More specifically, during the reaction, the polymeric auxiliaries release the bound polar organic solvent molecules through local solvent structure rearrangement, changing the total entropy of the system and forming a nucleation thrust; at the same time, the flexible segments in the polymeric auxiliaries provide a transient confinement effect, inhibiting the disordered growth of the crystal phase.

[0020] In some embodiments of the present invention, the polymeric auxiliaries are polymeric compounds containing protons or hydrogen bond acceptors.

[0021] In some embodiments of the present invention, the polymeric auxiliaries are polymeric compounds containing hydroxyl groups and ether bonds.

[0022] In some embodiments of the present invention, the polymeric additive is a polyethylene glycol polymer with a number-average molecular weight controlled to be 400-2000 Da.

[0023] In some embodiments of the present invention, the metal source includes at least one of a divalent metal source, a trivalent metal source, and a tetravalent metal source.

[0024] In some embodiments of the present invention, the organic ligand is one of phthalic acid BDC and 5-aminoisophthalic acid AMBA.

[0025] In some embodiments of the present invention, the liquid reaction medium further includes small molecule compounds with biological activity; the small molecule compounds are trapped inside the framework during the crystal growth stage to achieve in-situ stable encapsulation and controlled release.

[0026] In some embodiments of the present invention, a high-speed centrifugal field with a rotation speed of 5000-12000 rpm is applied in the reaction for 1-3 min; so that the metal-organic framework material crystals are oriented under the action of centrifugal force, exhibiting macroscopic transparency.

[0027] In some embodiments of the present invention, the mild conditions specifically refer to a reaction temperature between -5°C and 65°C and a reaction pressure at atmospheric pressure.

[0028] In some embodiments of the present invention, the reaction time is 15 to 30 minutes.

[0029] In some embodiments of the present invention, the polar solvent is one of water, N,N-dimethylformamide (DMF), and dimethyl sulfoxide (DMSO).

[0030] In some embodiments of the present invention, the reaction process may employ a continuous solid feeding method.

[0031] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0032] (1) The method for rapid synthesis of metal-organic framework materials under mild conditions of the present invention does not rely on traditional thermodynamic driving force, but is based on the underlying logic of "entropy-space synergistic regulation" mechanism. That is, the polymeric auxiliaries release a large number of bound small molecules (such as DMF, DMSO, etc.) through local solvent structure rearrangement, which significantly changes the total entropy of the system and forms a strong nucleation thrust. At the same time, the transient confinement effect provided by its flexible chain segments effectively inhibits the disordered growth of crystal phase and implements spatial locking of large-sized guest molecules, providing a new path for the green and efficient preparation of metal-organic framework materials, which has important scientific significance and broad industrialization prospects.

[0033] (2) The method for rapid synthesis of metal-organic framework materials under mild conditions of the present invention is applicable to divalent metal-MOF, trivalent metal source-MOF, and tetravalent metal-MOF. In particular, for the synthesis of tetravalent metal-organic frameworks, it breaks through the thermodynamic-kinetic coupling limitation in the existing tetravalent metal-organic framework synthesis methods, and realizes the synthesis of tetravalent metal-organic frameworks under room temperature and atmospheric pressure conditions, with a synthesis time of minutes.

[0034] (3) The method of rapid synthesis of metal-organic framework materials under mild conditions of the present invention realizes the controllable preparation of macroscopic single crystals or oriented thin films. A high-speed centrifugal field can be applied in the reaction system to make the crystals oriented under the action of centrifugal force. The obtained MOF material exhibits macroscopic transparency, is visible to the naked eye, and has photoelectric response properties.

[0035] (4) The method of rapidly synthesizing metal-organic framework materials under mild conditions of the present invention can simultaneously introduce small molecule compounds (such as curcumin, aspirin, ibuprofen, etc.) during the reaction of metal source and organic ligand. Due to the steric hindrance effect, the small molecules are trapped inside the framework during the crystal growth stage, realizing in-situ stable encapsulation and controlled release, which broadens its application field and can be better applied to petrochemical, environmental governance, energy storage and biomedicine fields.

[0036] (5) The method for rapid synthesis of metal-organic framework materials under mild conditions of the present invention can achieve continuous control of the crystal size of the product in the range of 3.3 nanometers to 2 millimeters by adjusting the type and amount of polymeric auxiliaries and the duration of the dynamic chemical environment; this provides a highly flexible degree of design freedom for different application scenarios (such as drug delivery, catalyst carriers, optical devices).

[0037] (6) The method for rapid synthesis of metal-organic framework materials under mild conditions of the present invention can adopt a continuous solid feeding method, which can meet the requirements of continuous scale-up, and also has the advantages of low energy consumption and safety. Attached Figure Description

[0038] Figure 1 Powder crystal diffraction pattern of curcumin@UIO-66, a metal-organic framework material prepared in Example 1 of the present invention.

[0039] Figure 2 The images show physical images of the metal-organic framework material curcumin@UIO-66 prepared in Example 1 and the metal-organic framework material UIO-66 prepared in Example 3 of the present invention, wherein (a) is curcumin@UIO-66 and (b) is UIO-66.

[0040] Figure 3 Powder crystal diffraction pattern of curcumin@UIO-66 transparent sheet, a metal-organic framework material prepared in Example 2 of the present invention.

[0041] Figure 4 A photograph of the transparent sheet of curcumin@UIO-66, a metal-organic framework material prepared in Example 2 of the present invention.

[0042] Figure 5Powder crystal diffraction pattern of UIO-66, a metal-organic framework material prepared in Example 3 of the present invention.

[0043] Figure 6 SEM image of UIO-66, a metal-organic framework material prepared for Example 3 of the present invention.

[0044] Figure 7 Powder crystal diffraction pattern of zirconium-pyromellitic acid (MOF), a metal-organic framework material prepared in Example 4 of the present invention.

[0045] Figure 8 Powder crystal diffraction pattern of the copper-manganese mixed metal-organic framework material HKUST-1 prepared in Example 5 of the present invention.

[0046] Figure 9 SEM image of the copper-manganese hybrid HKUST-1 metal-organic framework material prepared in Example 5 of the present invention.

[0047] Figure 10 Powder crystal diffraction pattern of MOF-808, a metal-organic framework material prepared in Example 6 of the present invention.

[0048] Figure 11 SEM image of MOF-808, a metal-organic framework material prepared for Example 6 of the present invention.

[0049] Figure 12 The powder crystal diffraction pattern of HKUST-1, a copper-manganese mixed metal-organic framework material prepared by hydrothermal method in Comparative Example 2 of the present invention, is shown. Detailed Implementation

[0050] The present invention is further described below through specific embodiments, but the scope of protection of the present invention is not limited thereto.

[0051] Example 1: Synthesis of curcumin@UIO-66 at low temperature

[0052] Instruments: 250mL beaker, centrifuge tubes, glass rod, 50mL graduated cylinder, ice bath, analytical balance, high-speed centrifuge, vacuum oven.

[0053] Reagents: Zirconium oxychloride octahydrate (Maclean's analytical grade), terephthalic acid (Maclean's analytical grade), N,N-dimethylformamide (Sinopharm analytical grade), anhydrous ethanol (Sinopharm analytical grade), PPG-400 (Yosex sample chemically pure), curcumin (Maclean's bio-pure).

[0054] Implementation steps:

[0055] (1) Weigh 2.415g zirconium chloride octahydrate, 1.245g terephthalic acid, and 150mg curcumin, add them to a 250mL beaker, and measure a total of 75mL N,N-dimethylformamide in two portions using a 50mL graduated cylinder. Stir with a glass rod until the solid is completely dissolved.

[0056] (2) Measure 40 mL of PPG-400 using a 50 mL graduated cylinder and slowly add it to the beaker while stirring until the system is clear.

[0057] (3) Start cooling while stirring. Control the temperature to -5 degrees Celsius using the temperature control system of the ice bath. Stop stirring after the temperature stabilizes.

[0058] (4) Wait for the reaction to proceed for about 45 minutes, then transfer the reaction system to a centrifuge tube and centrifuge at 5500 rpm for 2 minutes to obtain a centrifuge cake.

[0059] (5) Pour off the supernatant, add anhydrous ethanol to replace the solvent, and let it sit overnight.

[0060] (6) Centrifuge again, set to 5500 rpm and centrifuge for 2 minutes to obtain centrifuged cake.

[0061] (7) Transfer the solid to a beaker, break it up with a glass rod, put it in a vacuum oven, set the temperature to 35 degrees Celsius and the vacuum degree to 0.05 mbar, and dry for 2 hours to obtain the orange-yellow product curcumin@UIO-66 238 mg.

[0062] The powder crystal diffraction pattern of curcumin@UIO-66 prepared in this embodiment is as follows: Figure 1 As shown, the actual object is as follows Figure 2 As shown in Figure (a), the 7.3° and 8.5° peaks are coupled into a single peak, and a rise occurs in the 20-40° range. The product is orange-yellow. This peak coupling and rise proves that curcumin is embedded in the material pores and affects the crystal diffraction results of the crystal through steric hindrance. At the same time, the color change is caused by the interaction between the framework and curcumin.

[0063] Example 2: Synthesis of curcumin@UIO-66 translucent film at room temperature

[0064] Instruments: 100mL beaker, centrifuge tubes, glass rod, 50mL graduated cylinder, water bath, analytical balance, high-speed centrifuge, oven.

[0065] Reagents: Zirconium oxychloride octahydrate (Maclean's analytical grade), terephthalic acid (Maclean's analytical grade), dimethyl sulfoxide (Sinopharm analytical grade), anhydrous ethanol (Sinopharm analytical grade), PPG-1000 (Yosex sample chemically pure), curcumin (Maclean's bio-pure).

[0066] Implementation steps:

[0067] (1) Weigh 0.4382g zirconium chloride octahydrate, 0.2496g terephthalic acid, and 5mg curcumin, add them to a 100mL beaker, measure 17mL of dimethyl sulfoxide using a 50mL graduated cylinder, and stir with a glass rod until the solid substances are completely dissolved.

[0068] (2) Measure 6 mL of PPG-1000 using a 50 mL graduated cylinder and slowly add it to the beaker while stirring until the system is clear.

[0069] (3) Start temperature control while stirring. Control the temperature to 20 degrees Celsius through the temperature control system of the water bath. Stop stirring after the temperature stabilizes.

[0070] (4) Wait for the reaction to proceed for about 15 minutes, then transfer the reaction system to a centrifuge tube and centrifuge at 10,000 rpm for 1 minute to obtain a centrifuged cake.

[0071] (5) Pour off the supernatant, add anhydrous ethanol to replace the solvent, and let it sit overnight.

[0072] (6) Centrifuge again, set to 10,000 rpm for 1 minute to obtain a centrifuged cake.

[0073] (7) Transfer the solid intact to a beaker, place it in an oven, set the temperature to 60 degrees Celsius, and after 15 minutes, you will get 42.3 mg of orange translucent curcumin@UIO-66 tablets.

[0074] The powder crystal diffraction pattern of the translucent curcumin@UIO-66 tablets prepared in this embodiment is as follows: Figure 3 As shown, the actual object is as follows Figure 4 As shown. Compared to the opaque curcumin@UIO-66, the 7.3° and 8.5° peaks in the crystal diffraction pattern of the material are no longer coupled, while the 15° peak appears, indicating that the light transmittance of the material comes from the regulation of crystallinity and secondary assembly at the mesoscale.

[0075] Example 3: Synthesis of UIO-66 under mild conditions

[0076] Instruments: 100mL beaker, centrifuge tubes, glass rod, 50mL graduated cylinder, water bath, analytical balance, high-speed centrifuge, oven.

[0077] Reagents: Zirconium oxychloride octahydrate (Maclean's analytical grade), terephthalic acid (Maclean's analytical grade), dimethyl sulfoxide (Sinopharm analytical grade), anhydrous ethanol (Sinopharm analytical grade), PEG-400 (Usox sample chemically pure).

[0078] Implementation steps:

[0079] (1) Weigh 0.4382g zirconium chloride octahydrate and 0.2496g terephthalic acid, add them to a 100mL beaker, measure 15mL of dimethyl sulfoxide with a 50mL graduated cylinder, and stir with a glass rod until the solid substances are completely dissolved.

[0080] (2) Measure 12 mL of PEG-400 using a 50 mL graduated cylinder and slowly add it to the beaker while stirring until the system becomes clear.

[0081] (3) Start temperature control while stirring. Control the temperature to 60 degrees Celsius using the temperature control system of the water bath. Stop stirring after the temperature stabilizes.

[0082] (4) Wait for the reaction to proceed for about 12 minutes, then transfer the reaction system to a centrifuge tube and centrifuge at 10,000 rpm for 1 minute to obtain a centrifuged cake.

[0083] (5) Pour off the supernatant, add anhydrous ethanol to replace the solvent, and let it sit overnight.

[0084] (6) Centrifuge again, set to 10,000 rpm for 1 minute to obtain a centrifuged cake.

[0085] (7) Transfer the solid to a beaker, break it up with a glass rod and put it in an oven. Set the temperature to 100 degrees Celsius and wait for 2 hours to obtain 0.3494 g of white UIO-66 crystal powder.

[0086] The powder crystal diffraction pattern of UIO-66 prepared in this embodiment is as follows: Figure 5 As shown, the actual object is as follows Figure 2 As shown in (b); SEM images are as follows Figure 6 As shown in the figure. Combined with the SEM results, it can be seen that the material is composed of small spheres with a diameter of about 2 micrometers formed by the stacking of lamellar structures in the mesoscopic region. Therefore, the debroadening at low angles is relatively severe, but the broadening in the high-angle region is relatively weak. The special structure brings about special crystal diffraction results, and the crystallinity is good.

[0087] Example 4: Mild-condition synthesis of zirconium-pyromellitic acid MOF

[0088] Instruments: 100mL beaker, centrifuge tubes, glass rod, 50mL graduated cylinder, water bath, analytical balance, high-speed centrifuge, oven.

[0089] Reagents: Zirconium oxychloride octahydrate (Maclean's analytical grade), pyromellitic acid (Maclean's analytical grade), N-methylpyrrolidone (Sinopharm analytical grade), anhydrous ethanol (Sinopharm analytical grade), vinylpyrrolidone K15 (Usox sample chemically pure).

[0090] Implementation steps:

[0091] (1) Weigh 0.4382g zirconium chloride octahydrate and 0.3820g pyromellitic acid, add them to a 100mL beaker, measure 30mL of N-methylpyrrolidone with a 50mL graduated cylinder, and stir with a glass rod until the solid is completely dissolved.

[0092] (2) Measure 15 mL of vinylpyrrolidone K1 using a 50 mL graduated cylinder and slowly add it to the beaker while stirring until the system becomes clear.

[0093] (3) Start temperature control while stirring. Control the temperature to 45 degrees Celsius through the temperature control system of the water bath. Stop stirring after the temperature stabilizes.

[0094] (4) Wait for the reaction to proceed for about 75 minutes, then transfer the reaction system to a centrifuge tube and centrifuge at 10,000 rpm for 1 minute to obtain a centrifuged cake.

[0095] (5) Pour off the supernatant, add anhydrous ethanol to replace the solvent, and let it sit overnight.

[0096] (6) Centrifuge again, set to 10,000 rpm for 1 minute to obtain a centrifuged cake.

[0097] (7) Transfer the solid to a beaker, break it up with a glass rod and put it in an oven. Set the temperature to 100 degrees Celsius and wait for 2 hours to obtain 0.1299 g of white zirconium-pyromellitic acid MOF crystal powder.

[0098] The powder crystal diffraction pattern of the zirconium-pyromellitic acid MOF prepared in this embodiment is as follows: Figure 7 As shown, zirconium-pyromellitic acid MOF is based on a single acid radical. Due to its large steric hindrance and the property of equivalent coordination at adjacent sites, the interplanar spacing of the UIO-66-like structure formed by it is amplified, so the characteristic peaks are shifted to smaller angles. Furthermore, due to the reduction in particle size, the broadening is enhanced, but the signal-to-noise ratio is good, which proves that the crystallinity is good.

[0099] Example 5: Synthesis of a copper-manganese mixed HKUST-1

[0100] Instruments: 100mL beaker, centrifuge tubes, glass rod, 50mL graduated cylinder, analytical balance, high-speed centrifuge, oven.

[0101] Reagents: Copper oxalate monohydrate (Maclean's analytical grade), anhydrous manganese chloride (Maclean's analytical grade), trimesic acid (Maclean's analytical grade), dimethyl sulfoxide (Sinopharm analytical grade), anhydrous ethanol (Sinopharm analytical grade), PPG-800 (Usox sample chemically pure).

[0102] Implementation steps:

[0103] (1) Weigh 0.2995g copper oxalate monohydrate, 0.3775g anhydrous manganese chloride, and 0.6300g pyromellitic acid, add them to a 100mL beaker, measure 50mL of dimethyl sulfoxide using a 50mL graduated cylinder, and stir with a glass rod until dissolved and balanced.

[0104] (2) Measure 20 mL of PPG-800 using a 50 mL graduated cylinder and slowly add it to the beaker while stirring until the system is clear.

[0105] (3) Stop stirring. The temperature is 22.2 degrees Celsius. The system turns bright green instantly, forming a colloid with the Tyndall effect.

[0106] (4) Wait for the reaction to proceed for about 1 minute, then transfer the reaction system to a centrifuge tube and centrifuge at 10,000 rpm for 1 minute to obtain a centrifuged cake.

[0107] (5) Pour off the supernatant to obtain a centrifuged cake, and add anhydrous ethanol to replace the solvent.

[0108] (6) Pour the supernatant back into the beaker, stir, and let stand. The system will turn bright green instantly, forming a colloid with the Tyndall effect. Repeat steps (4) to (6) until the system does not turn bright green after being added back, but is yellowish-green.

[0109] (7) Pour off the supernatant from the centrifuged cake, add anhydrous ethanol to replace the solvent, and let it sit overnight.

[0110] (8) Centrifuge again, set to 10,000 rpm for 1 minute to obtain a centrifuged cake.

[0111] (9) Transfer the solid to a beaker, break it up with a glass rod and put it in an oven. Set the temperature to 100 degrees Celsius and wait for 2 hours to obtain 0.5341 g of blue-green copper-manganese mixed HKUST-1 crystal powder.

[0112] The powder crystal diffraction pattern of the copper-manganese mixed HKUST-1 prepared in this embodiment is as follows: Figure 8 As shown; SEM photos are as follows Figure 9 As shown. The product obtained by SEM is a crystalline fragment, and the XRD peak broadening is very weak, indicating good crystallinity.

[0113] Example 6: Continuous solid feed synthesis of MOF-808

[0114] Instruments: 100mL beaker, centrifuge tubes, glass rod, 25mL graduated cylinder, water bath, analytical balance, high-speed centrifuge, oven.

[0115] Reagents: Zirconium oxychloride octahydrate (Maclean's analytical grade), trimesic acid (Maclean's analytical grade), anhydrous ethanol (Sinopharm analytical grade), PPG-400 (Yosex sample chemically pure), tap water, dimethyl sulfoxide (Sinopharm analytical grade).

[0116] Implementation steps:

[0117] (1) Weigh 0.4382g zirconium chloride octahydrate and 0.1584g terephthalic acid, and add them to 100mL beakers 1 and 2 respectively. Measure 5mL of water with a 50mL graduated cylinder and add it to beaker 1. Measure 10mL of dimethyl sulfoxide and add it to beaker 2. Stir with a glass rod until the solid substances are completely dissolved.

[0118] (2) Measure 5 mL of PPG-400 using a 25 mL graduated cylinder and slowly add it to beaker 1 while stirring until the system is clear.

[0119] (3) Place beaker 1 in a water bath and start temperature control while stirring. Control the temperature to 45 degrees Celsius through the temperature control system of the water bath. After the temperature stabilizes, add the liquid in beaker 2 to beaker 1, mix well, and set the stirring speed to 200 revolutions per minute.

[0120] (4) Two minutes later, weigh out 0.4382 g of zirconium chloride octahydrate and 0.1584 g of terephthalic acid, and slowly add them to the reaction system in multiple batches.

[0121] (5) Wait for the reaction to proceed for about 35 minutes, then transfer the reaction system to a centrifuge tube and centrifuge at 10,000 rpm for 1 minute to obtain a centrifuged cake.

[0122] (6) Pour off the supernatant, add anhydrous ethanol to replace the solvent, and let it sit overnight.

[0123] (7) Centrifuge again, set to 10,000 rpm for 1 minute to obtain a centrifuged cake.

[0124] (8) Transfer the solid to a beaker, break it up with a glass rod and put it in an oven. Set the temperature to 100 degrees Celsius and wait for 2 hours to obtain 0.5659 g of white MOF-808 crystal powder.

[0125] The powder crystal diffraction pattern of MOF-808 prepared in this embodiment is as follows: Figure 10 As shown; SEM photos are as follows Figure 11 As shown in the figure. The SEM results show that the material is composed of small spheres with a diameter of about 2 micrometers formed by the stacking of lamellar structures in the mesoscopic region. Therefore, the debroadening at low angles is relatively severe, but the broadening at high angles is relatively weak. The special structure brings about special crystal diffraction results, and the crystallinity is good.

[0126] Comparative Example 1: Synthetic system without polymeric additives

[0127] Instruments: 100mL beaker, centrifuge tubes, glass rod, 50mL graduated cylinder, water bath, analytical balance, high-speed centrifuge, oven.

[0128] Reagents: Zirconium oxychloride octahydrate (Maclean's analytical grade), terephthalic acid (Maclean's analytical grade), dimethyl sulfoxide (Sinopharm analytical grade), anhydrous ethanol (Sinopharm analytical grade)

[0129] Implementation steps:

[0130] (1) Weigh 0.4382g zirconium chloride octahydrate, 0.2496g terephthalic acid, and 5mg curcumin, add them to a 100mL beaker, measure 17mL of dimethyl sulfoxide using a 50mL graduated cylinder, and stir with a glass rod until the solid substances are completely dissolved.

[0131] (2) Start temperature control while stirring. Control the temperature to 20 degrees Celsius through the temperature control system of the water bath. Stop stirring after the temperature stabilizes.

[0132] (3) After standing for a long time, about 14 days, the system begins to show colloidal characteristics and turns white.

[0133] (4) Transfer it to a centrifuge tube and centrifuge. The white color disappears and no product can be obtained.

[0134] Comparative Example 2: Hydrothermal Synthesis of Copper-Manganese Mixed HKUST-1

[0135] Instruments: Hydrothermal reactor (100 mL, PTFE liner), drying oven (100℃), centrifuge (speed ≥3000 rpm), 50 mL graduated cylinder

[0136] Reagents: Copper nitrate (Chinese pharmaceutical analytical grade), manganese acetate (Chinese pharmaceutical analytical grade), trimellitic acid (Chinese pharmaceutical analytical grade), deionized water, anhydrous ethanol (Chinese pharmaceutical analytical grade)

[0137] 1. Solution preparation:

[0138] a. Dissolve 1.48 g of copper nitrate and 0.367 g of manganese acetate in 30 mL of deionized water.

[0139] b. Dissolve 1.29 g of pyromellitic acid in 30 mL of anhydrous ethanol.

[0140] 2. Mixing reaction: Transfer the two solutions to a 100 mL hydrothermal reactor and react at 120°C for 12 hours.

[0141] 3. Post-processing: After cooling to room temperature, wash the product three times with deionized water and anhydrous ethanol alternately, and centrifuge each time (3000 rpm, 5 minutes).

[0142] 4. Drying: The product was dried in a drying oven at 100℃ for 12 hours to obtain 1.37g of blue powder CuMn-BTC material.

[0143] The powder crystal diffraction pattern of CuMn-BTC prepared in this comparative example is as follows: Figure 12 As shown. Compared with Example 5, the signal-to-noise ratio of this product is slightly lower, and there is a series of impurity phase peaks at around 30°, indicating that Cu Mn did not achieve high-entropy mixing, but rather a few isolated impurity phases; while the XRD results of Example 5 have a higher signal-to-noise ratio, fewer peaks in the low-angle region, and weaker impurity peak intensity, indicating a higher degree of mixing and good crystallinity.

[0144] Those skilled in the art will readily understand that the above description is merely an embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for rapid synthesis of metal-organic framework materials under mild conditions, characterized in that, Includes the following steps: At least one metal source and at least one organic ligand are added to a polar organic solvent and mixed to form a liquid reaction medium; A polymeric auxiliary agent is added to the liquid reaction medium to form and maintain a dynamic chemical environment that guides the orderly assembly of the metal source and the organic ligand in the liquid reaction, so that the metal source and the organic ligand react and crystallize to obtain a metal-organic framework material. The formation of the dynamic chemical environment is as follows: the polymeric auxiliary agent induces the generation of transient ordered microregions in a polar organic solvent, forming a local entropy increase effect and a spatial confinement environment, so that the metal source and the organic ligand undergo directional cooperative self-assembly.

2. The method for rapid synthesis of metal-organic framework materials under mild conditions according to claim 1, characterized in that, The polymeric auxiliaries are polymeric compounds containing protons or hydrogen bond acceptors.

3. The method for rapid synthesis of metal-organic framework materials under mild conditions according to claim 1, characterized in that, The polymeric additive is a polymeric compound containing hydroxyl groups and ether bonds.

4. The method for rapid synthesis of metal-organic framework materials under mild conditions according to claim 1, characterized in that, The polymeric additive is a polyethylene glycol polymer with a number-average molecular weight controlled at 400-2000 Da.

5. The method for rapid synthesis of metal-organic framework materials under mild conditions according to claim 1, characterized in that, The metal source includes at least one of divalent metal sources, trivalent metal sources, and tetravalent metal sources.

6. The method for rapid synthesis of metal-organic framework materials under mild conditions according to claim 1, characterized in that, The organic ligand is one of phthalic acid BDC and 5-aminoisophthalic acid AMBA.

7. The method for rapid synthesis of metal-organic framework materials under mild conditions according to claim 1, characterized in that, The liquid reaction medium also includes bioactive small molecule compounds; these small molecule compounds are trapped inside the framework during the crystal growth stage, achieving in-situ stable encapsulation and controlled release.

8. The method for rapid synthesis of metal-organic framework materials under mild conditions according to claim 1, characterized in that, The reaction is subjected to a high-speed centrifugal field with a rotation speed of 5000-12000 rpm for 1-3 min, so that the metal-organic framework material crystals are oriented under the action of centrifugal force, exhibiting macroscopic transparency.

9. The method for rapid synthesis of metal-organic framework materials under mild conditions according to claim 1, characterized in that, The mild conditions specifically refer to a reaction temperature between -5°C and 65°C and a reaction pressure at atmospheric pressure.

10. The method for rapid synthesis of metal-organic framework materials under mild conditions according to claim 1, characterized in that, The reaction time is 15-30 minutes.

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