A sheet-like bismuth-based metal organic framework material and a preparation method thereof

Abstract

The application discloses a kind of sheet bismuth-based metal organic framework materials and preparation method thereof, comprising the following steps: bismuth salt and polybasic acid organic ligand are mixed, then mixed with grinding ball, ball milling treatment, obtain bismuth-based metal organic framework material.The application prepares bismuth-based metal organic framework material with sheet morphology structure by mechanical ball milling method, by using mechanical energy in ball mill to crush reactant, promote the rapid progress of bismuth metal ion and organic ligand reaction, the whole reaction process does not need solvent, or only needs trace amount of solvent, avoid the large use of organic solvent.The application can directly promote reaction at room temperature by mechanical force, and reaction time is short, yield is high, energy consumption is low, green and environmental protection.The bismuth-based metal organic framework material has unique sheet morphology structure, high specific surface area and high structural stability and the like characteristics, and size can be controlled, can be widely used in carbon dioxide adsorption reduction, adsorption of pollutants in water and the like fields.

Description

Technical Field

[0001] This invention relates to the field of organic-inorganic hybrid materials technology, and in particular to a sheet-like bismuth-based metal-organic framework material and its preparation method. Background Technology

[0002] Numerous methods for preparing bismuth-based metal-organic framework materials have been reported. For example, Chinese patent CN117209791A discloses a method for preparing bismuth-containing metal-organic framework porous nanomaterials via a solvothermal approach. This material is based on the central metal Bi. 3+ As a connecting node, organic ligands are used as bridges to connect with Bi 3+ Chelating coordination links form one-dimensional, two-dimensional, or three-dimensional network porous topologies. However, existing preparation methods are mostly based on hydrothermal and solvothermal methods, requiring high temperatures and large amounts of solvent, resulting in high energy consumption and environmental unfriendliness. In recent years, various green synthesis methods have been developed, such as microwave reaction methods and ultrasonic methods. For example, Chinese patent CN116333333A discloses a method for preparing bismuth-based metal-organic frameworks using a microwave reaction method. The bismuth-based metal-organic frameworks obtained by this method are regular hexagonal prisms with uniform crystal size. Chinese patent CN113773348A discloses the preparation of bismuth-based metal-organic frameworks in an aqueous system using a secondary ultrasonic growth method. The bismuth-based metal-organic frameworks have an elongated morphology with a base diameter on the nanometer scale. Chinese patent CN113773348A discloses a method for preparing bismuth-based metal-organic frameworks using an ultrasonic reaction method, with a yield in the hundreds of milligrams range, while requiring ultrasonic treatment for 5 hours. However, these synthesis methods still have many drawbacks. For example, microwave reaction methods have high equipment costs and strict requirements for reaction vessel materials; ultrasonic reaction methods suffer from problems such as ultrasonic field uniformity, low energy transfer efficiency, and difficulty in scaling up the reaction. At the same time, most synthesis methods must use organic solvents as the reaction system, which will generate toxic and harmful waste liquids and pose certain dangers, thus limiting their large-scale production and practical application.

[0003] Against this backdrop, mechanical ball milling, as an emerging mechanochemical synthesis technique, has become a research hotspot in the field of MOF preparation due to its high efficiency, green nature, and low cost.

[0004] Although mechanical ball milling has been reported in the preparation of metal framework materials, for example, Chinese patent CN118047955A discloses a mechanochemical method for preparing high specific surface area metal-organic framework materials. This method employs a two-step ball milling process assisted by a trace amount of organic solvent to degrade waste polyethylene terephthalate (PET) into terephthalate and ethylene glycol through mechanochemical action under a strongly alkaline environment. Subsequently, under the mechanochemical action assisted by a trace amount of organic solvent, the terephthalate coordinates with metal ions to prepare high specific surface area MOFs. Chinese patent CN119463206 A discloses a method for preparing a UTSA-16 structured metal-organic framework, comprising the following steps: adding a metal salt and potassium citrate sequentially to an auxiliary solvent, then adding an alkaline solution, adjusting the pH value to 8-13, and then processing by ball milling to obtain a reaction solution; centrifuging the reaction solution, collecting the solid portion, washing with diethyl ether, soaking in methanol, and drying to obtain a precursor; activating the precursor at 80-90℃ to remove the solvent from the pores, thereby obtaining the UTSA-16 structured metal-organic framework.

[0005] However, there are no reports of using mechanical ball milling to prepare bismuth-based metal-organic framework materials with specific morphologies, namely sheet-like bismuth. Summary of the Invention

[0006] Therefore, the purpose of this invention is to provide a sheet-like bismuth-based metal-organic framework material and its preparation method. This preparation method features low cost, simple process, safe and environmentally friendly operation, high yield, and low energy consumption.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] The first aspect of the present invention provides a method for preparing a sheet-like bismuth-based metal-organic framework material, comprising the following steps:

[0009] S1. Mix bismuth salt and polybasic acid organic ligand to obtain a mixture;

[0010] S2. The obtained mixture is mixed with grinding balls and ball-milled to obtain a sheet-like bismuth-based metal-organic framework material.

[0011] Preferably, in order to reduce energy loss, increase product yield, and shorten the preparation cycle, a trace amount of auxiliary solvent can be added during the grinding process to accelerate the reaction.

[0012] Preferably, the grinding balls used for ball milling are zirconia balls;

[0013] Preferably, to ensure the formation of bismuth-based metal-organic framework materials, the mass ratio of the bismuth salt to the polybasic acid organic ligand is 1:1-10;

[0014] More preferably, in order to improve the product yield, the mass ratio of the bismuth salt to the polybasic acid organic ligand is 1:1-5.

[0015] Preferably, the ball milling process is performed at room temperature, the ball milling speed is 500-5000 rpm / min, and the ball milling time is 0.5 min to 10 min.

[0016] Preferably, the bismuth salt is one or a combination of two or more of bismuth nitrate pentahydrate, bismuth acetate, and bismuth oxynitrate.

[0017] Preferably, the polybasic acid organic ligand is one or a combination of two or more of 1,3,5-pyromellitic acid, triazine-2,4,6-triyl-tribenzoic acid, and biphenyl-3,3ˊ,5,5ˊ-tetracarboxylic acid. Specifically, 1,3,5-pyromellitic acid reacts with bismuth salts to form CAU-7 and CAU-17; triazine-2,4,6-triyl-tribenzoic acid reacts with bismuth salts to form CAU-35; and biphenyl-3,3ˊ,5,5ˊ-tetracarboxylic acid reacts with bismuth salts to form NOTT-220. CAU-7, CAU-17, CAU-35, and NOTT-220 are all bismuth-based metal-organic framework materials with different topological structures.

[0018] Preferably, the ball milling auxiliary solvent is one or a combination of two or more of methanol, ethanol, DMF, and 1,2-propanediol.

[0019] A second aspect of the present invention provides a sheet-like bismuth-based metal-organic framework material obtained by the above preparation method.

[0020] A third aspect of the present invention provides the application of the above-described sheet-like bismuth-based metal-organic framework material in carbon dioxide adsorption and reduction as well as in the adsorption of pollutants in water.

[0021] The present invention has the following beneficial effects:

[0022] (1) This invention employs mechanical ball milling to prepare bismuth-based metal-organic framework materials with a sheet-like structure. By utilizing mechanical energy to pulverize the reactants in a ball mill, the reaction between bismuth metal ions and organic ligands is rapidly promoted. The entire reaction process requires no solvent, or only a trace amount of auxiliary solvent, thus avoiding the extensive use of organic solvents. Compared with the traditional solvothermal method, the preparation method of this invention can directly drive the reaction at room temperature using mechanical force, and it features short reaction time, high yield, low energy consumption, and is environmentally friendly.

[0023] (2) In the preparation method of this invention, the ball milling equipment used has a simple structure and its parameters (such as ball milling time, rotation speed, and the material and size of the balls and the vessel) are easy to control, thereby controlling the particle size, morphology, specific surface area, and other characteristics of the desired product. This controllability makes the ball milling method highly flexible and adaptable in the synthesis of bismuth-based metal-organic frameworks. At the same time, the addition of trace amounts of auxiliary solvent during the ball milling process can accelerate the reaction and result in a higher product yield.

[0024] (3) The bismuth-based metal-organic framework material prepared by the present invention has unique sheet-like morphology, high specific surface area and high structural stability, and its size can be controlled. It can be widely used in the fields of carbon dioxide adsorption and reduction (the selectivity of the product formic acid is greater than 90% and the byproduct is gaseous hydrogen) and adsorption of pollutants (such as rhodamine) in water. Attached Figure Description

[0025] Figure 1 Here is a SEM image of the bismuth-based metal-organic framework material prepared in Example 1;

[0026] Figure 2 The image shows the XRD pattern of the bismuth-based metal-organic framework material prepared in Example 1.

[0027] Figure 3 Stability testing of the bismuth-based metal-organic framework material prepared in Example 1 at different pH values;

[0028] Figure 4 Here is a SEM image of the bismuth-based metal-organic framework material prepared in Example 2;

[0029] Figure 5 The XRD patterns of the sample products prepared in Comparative Example 1 and Comparative Example 2 are shown.

[0030] Figure 6 The adsorption diagram of RhB on the bismuth-based metal-organic framework material prepared in Example 1 is shown.

[0031] Figure 7 The electrochemical carbon dioxide reduction performance of the bismuth-based metal-organic framework material prepared in Example 1 is shown. Detailed Implementation

[0032] To facilitate understanding of the present invention, it will be described in more detail below. However, it should be understood that the present invention can be implemented in many different forms and is not limited to the embodiments or examples described herein. Rather, these embodiments or examples are provided to make the disclosure of the present invention more thorough and complete.

[0033] Example 1

[0034] 30 mg of bismuth nitrate pentahydrate and 150 mg of 1,3,5-pyromellitic acid were mixed and stirred until homogeneous to obtain a mixture. 100 μl of ethanol was added dropwise to the mixture and stirred until homogeneous. The container containing the mixture sample was placed in a ball mill. Zirconia grinding balls were added to the ball mill at a ball-to-material ratio of 10:1, and the mixture was ball-milled at 4000 rpm / min for 1 min. The final product was transferred to a large beaker, methanol was added, and the mixture was centrifuged and washed three times to obtain the bismuth-based metal-organic framework material. The obtained bismuth-based metal-organic framework material was found to be sheet-like, with a length of 800 nm to 1.5 μm and a uniform size distribution, exhibiting a specific surface area of ​​425 m². 2 / g, yield 95%.

[0035] Example 2

[0036] 30g of bismuth nitrate pentahydrate and 150g of 1,3,5-pyromellitic acid were mixed and stirred until homogeneous to obtain a mixture. 5ml of ethanol was added dropwise to the mixture and stirred until homogeneous. The container containing the mixture sample was placed in a ball mill. Zirconia grinding balls were added to the ball mill at a ball-to-material ratio of 10:1, and the mixture was ball-milled at 4000rpm / min for 3min. The final product was transferred to a large beaker, methanol was added, and the mixture was centrifuged and washed three times to obtain the bismuth-based metal-organic framework material. The obtained bismuth-based metal-organic framework material was found to be sheet-like, with a length of 800nm-1.5μm and a uniform size distribution, exhibiting a specific surface area of ​​387m². 2 / g, yield 90%.

[0037] Example 3

[0038] 30 mg of bismuth nitrate pentahydrate and 30 mg of biphenyl-3,3ˊ,5,5ˊ-tetracarboxylic acid were mixed and stirred until homogeneous to obtain a mixture. 100 μl of methanol was added dropwise to the mixture and stirred until homogeneous. The container containing the mixture sample was placed in a ball mill. Zirconia grinding balls were added to the ball mill at a ball-to-material ratio of 10:1, and the mixture was ball-milled at 3000 rpm / min for 1 min. The final product was transferred to a large beaker, methanol was added, and the mixture was centrifuged and washed three times to obtain a bismuth-based metal-organic framework material. The obtained bismuth-based metal-organic framework material was found to be sheet-like, with a length of 800 nm to 1.5 μm and a uniform size distribution, exhibiting a specific surface area of ​​395 m². 2 / g, yield 85%.

[0039] Example 4

[0040] 30 mg of bismuth nitrate pentahydrate and 150 mg of 1,3,5-pyromellitic acid were mixed and stirred until homogeneous to obtain a mixture. 100 μl of DMF was added dropwise to the mixture and stirred until homogeneous. The container containing the mixture sample was placed in a ball mill. Zirconia grinding balls were added to the ball mill at a ball-to-material ratio of 10:1, and the mixture was ball-milled at 4000 rpm / min for 1 min. The final product was transferred to a large beaker, methanol was added, and the mixture was centrifuged and washed three times to obtain the bismuth-based metal-organic framework material. The obtained bismuth-based metal-organic framework material was found to be sheet-like, with a length of 800 nm to 1.5 μm and a uniform size distribution, exhibiting a specific surface area of ​​418 m². 2 / g, yield 95%.

[0041] Example 5

[0042] 30 mg of bismuth nitrate pentahydrate and 150 mg of 1,3,5-pyromellitic acid were mixed and stirred until homogeneous to obtain a mixture. 100 μl of DMF was added dropwise to the mixture and stirred until homogeneous. The container containing the mixture sample was placed in a ball mill. Zirconia grinding balls were added to the ball mill at a ball-to-material ratio of 10:1, and the mixture was ball-milled at 3000 rpm for 3 min. The final product was transferred to a large beaker, methanol was added, and the mixture was centrifuged and washed three times to obtain the bismuth-based metal-organic framework material. The obtained bismuth-based metal-organic framework material was found to be sheet-like, with a length of 1.8 μm-3.2 μm and a uniform size distribution, and a specific surface area of ​​367 m². 2 / g, yield 85%.

[0043] Example 6

[0044] 30 mg of bismuth nitrate pentahydrate and 150 mg of biphenyl-3,3ˊ,5,5ˊ-tetracarboxylic acid were mixed and stirred until homogeneous to obtain a mixture. 100 μl of DMF was added dropwise to the mixture and stirred until homogeneous. The container containing the mixture sample was placed in a ball mill. Zirconia grinding balls were added to the ball mill at a ball-to-material ratio of 10:1, and the mixture was ball-milled at 3000 rpm for 3 min. The final product was transferred to a large beaker, methanol was added, and the mixture was centrifuged and washed three times to obtain a bismuth-based metal-organic framework material. The obtained bismuth-based metal-organic framework material was found to be sheet-like, with a length of 1.5 μm-3.0 μm and a uniform size distribution, and a specific surface area of ​​380 m². 2 / g, yield 90%.

[0045] Example 7

[0046] 30 mg of bismuth nitrate pentahydrate and 150 mg of 1,3,5-pyromellitic acid were mixed and stirred until homogeneous to obtain a mixture. 100 μl of DMF was added dropwise to the mixture and stirred until homogeneous. The container containing the mixture sample was placed in a ball mill. Zirconia grinding balls were added to the ball mill at a ball-to-material ratio of 10:1, and the mixture was ball-milled at 2000 rpm for 3 min. The final product was transferred to a large beaker, methanol was added, and the mixture was centrifuged and washed three times to obtain the bismuth-based metal-organic framework material. The obtained bismuth-based metal-organic framework material was found to be sheet-like, with a length of 3.5 μm-5.0 μm and a uniform size distribution, and a specific surface area of ​​344 m². 2 / g, yield 80%.

[0047] Example 8

[0048] 30 mg of bismuth nitrate pentahydrate and 300 mg of 1,3,5-pyromellitic acid were mixed and stirred until homogeneous to obtain a mixture. 100 μl of DMF was added dropwise to the mixture and stirred until homogeneous. The container containing the mixture sample was placed in a ball mill. Zirconia grinding balls were added to the ball mill at a ball-to-material ratio of 10:1, and the mixture was ball-milled at 2000 rpm for 5 min. The final product was transferred to a large beaker, methanol was added, and the mixture was centrifuged and washed three times to obtain the bismuth-based metal-organic framework material. The obtained bismuth-based metal-organic framework material was found to be sheet-like, with a length of 3.3 μm-4.5 μm and a uniform size distribution, and a specific surface area of ​​358 m². 2 / g, yield 83%.

[0049] Example 9

[0050] 30 mg of bismuth nitrate pentahydrate and 150 mg of 1,3,5-pyromellitic acid were mixed and stirred until homogeneous to obtain a mixture. 100 μl of 1,2-propanediol was added dropwise to the mixture and stirred until homogeneous. The container containing the mixture sample was placed in a ball mill. Zirconia grinding balls were added to the ball mill at a ball-to-material ratio of 10:1, and the mixture was ball-milled at 1000 rpm for 5 min. The final product was transferred to a large beaker, methanol was added, and the mixture was centrifuged and washed three times to obtain the bismuth-based metal-organic framework material. The obtained bismuth-based metal-organic framework material was found to be sheet-like, with a length of 5.1 μm-6.8 μm and a uniform size distribution, and a specific surface area of ​​330 m². 2 / g, yield 80%.

[0051] Example 10

[0052] 30 mg of bismuth oxynitrate and 150 mg of 1,3,5-pyromellitic acid were mixed and stirred until homogeneous to obtain a mixture. 100 μl of ethanol was added dropwise to the mixture and stirred until homogeneous. The container containing the mixture sample was placed in a ball mill. Zirconia grinding balls were added to the ball mill at a ball-to-material ratio of 10:1, and the mixture was ball-milled at 1000 rpm for 5 min. The final product was transferred to a large beaker, methanol was added, and the mixture was centrifuged and washed three times to obtain the bismuth-based metal-organic framework material. The obtained bismuth-based metal-organic framework material was found to be sheet-like, with a length of 4.8 μm-5.8 μm and a uniform size distribution, and a specific surface area of ​​361 m². 2 / g, yield 85%.

[0053] Example 11

[0054] 30 mg of bismuth acetate and 150 mg of triazine-2,4,6-triyl-tribenzoic acid were mixed and stirred until homogeneous to obtain a mixture. 100 μl of methanol was added dropwise to the mixture and stirred until homogeneous. The container containing the mixture was placed in a ball mill, and zirconium oxide grinding balls were added at a ball-to-material ratio of 10:1. The mixture was then ball-milled at 500 rpm for 10 min. The final product was transferred to a large beaker, methanol was added, and the mixture was centrifuged and washed three times to obtain the bismuth-based metal-organic framework material. The obtained bismuth-based metal-organic framework material was found to be sheet-like, with a length of 7.5-9.5 μm and a uniform size distribution, and a specific surface area of ​​332 m². 2 / g, yield 85%.

[0055] Example 12

[0056] 30 mg of bismuth nitrate pentahydrate and 150 mg of triazine-2,4,6-triyl-tribenzoic acid were mixed and stirred until homogeneous to obtain a mixture. 80 μl of methanol was added dropwise to the mixture and stirred until homogeneous. The container containing the mixture was placed in a ball mill, and zirconium oxide grinding balls were added at a ball-to-material ratio of 10:1. The mixture was then ball-milled at 5000 rpm / min for 30 s. The final product was transferred to a large beaker, methanol was added, and the mixture was centrifuged and washed three times to obtain the bismuth-based metal-organic framework material. The obtained bismuth-based metal-organic framework material was found to be sheet-like, with a length of 800 nm to 1.5 μm and a uniform size distribution, exhibiting a specific surface area of ​​412 m². 2 / g, yield 95%.

[0057] Comparative Example 1

[0058] 30 mg of bismuth nitrate pentahydrate and 150 mg of 1,3,5-pyromellitic acid were mixed thoroughly to obtain a mixture. 100 μl of ethanol was added dropwise to the mixture and mixed thoroughly. The container holding the mixture was placed in a ball mill. Zirconia grinding balls were added to the ball mill at a ball-to-material ratio of 10:1, and the mixture was ball-milled at 400 rpm for 5 min. The final product was transferred to a large beaker, methanol was added, and the mixture was centrifuged and washed three times to obtain the sample. XRD analysis showed that the obtained product (sample) was a non-bismuth-based metal-organic framework material. Figure 5 .

[0059] Comparative Example 2

[0060] 30 mg of bismuth nitrate pentahydrate and 150 mg of 1,3,5-pyromellitic acid were mixed and stirred until homogeneous to obtain a mixture. 100 μl of ethanol was added dropwise to the mixture and stirred until homogeneous. The container holding the mixture was placed in a ball mill. Zirconia grinding balls were added to the ball mill at a ball-to-material ratio of 10:1, and the mixture was ball-milled at 200 rpm for 10 min. The final product was transferred to a large beaker, methanol was added, and the mixture was centrifuged and washed three times to obtain the sample. XRD analysis showed that the obtained product (sample) was a non-bismuth-based metal-organic framework material. Figure 5 .

[0061] Comparative Example 3

[0062] 30 mg of bismuth nitrate pentahydrate and 150 mg of 1,3,5-pyromellitic acid were mixed and stirred until homogeneous to obtain a mixture. The container holding the mixture was placed in a ball mill. Zirconia grinding balls were added to the ball mill at a ball-to-material ratio of 10:1, and the mixture was ball-milled at 1000 rpm for 5 minutes. The final product was transferred to a large beaker, methanol was added, and the mixture was centrifuged and washed three times to obtain the bismuth-based metal-organic framework material. The obtained bismuth-based metal-organic framework material was found to be sheet-like, with a length of 1.3 μm-2.8 μm, uniform size distribution, and a specific surface area of ​​381 m². 2 / g, yield 60%.

[0063] Comparative Example 4

[0064] 30 mg of bismuth nitrate pentahydrate and 150 mg of triazine-2,4,6-triyl-tribenzoic acid were mixed and stirred until homogeneous to obtain a mixture. The container holding the mixture was placed in a ball mill. Zirconia grinding balls were added to the ball mill at a ball-to-material ratio of 10:1, and the mixture was ball-milled at 3500 rpm for 1 min. The final product was transferred to a large beaker, methanol was added, and the mixture was centrifuged and washed three times to obtain the bismuth-based metal-organic framework material. The obtained bismuth-based metal-organic framework material was found to be sheet-like, with a length of 1.0 μm-2.3 μm, uniform size distribution, and a specific surface area of ​​393 m².2 / g, yield 67%.

[0065] The bismuth-based metal-organic framework materials prepared in Examples 1 and 2 were characterized, and the results are shown in the figure. Figure 1-3 .

[0066] from Figure 1 It can be seen that the bismuth-based metal-organic framework material prepared in Example 1 is sheet-like, with a length of 800 nm-1.5 μm and a uniform size distribution, and a specific surface area of ​​425 m². 2 / g.

[0067] from Figure 2 It can be seen that the bismuth-based metal-organic framework material prepared in Example 1 has good crystallinity and shows the unique layered diffraction peaks of bismuth-based metal-organic framework materials in the diffraction angle of 5°-50°. Furthermore, the positions of all diffraction peaks of the bismuth-based metal-organic framework material correspond one-to-one with the positions of diffraction peaks of the known CAU-17 crystal structure, indicating that the bismuth-based metal-organic framework material has the same crystal structure as CAU-17, that is, the obtained bismuth-based metal-organic framework material is CAU-17.

[0068] from Figure 3 It can be seen that the sheet-like bismuth-based metal-organic framework material has high stability in the pH range of 2-13.

[0069] from Figure 4 It can be seen that the bismuth-based metal-organic framework material prepared in Example 2 is sheet-like, with a length of 800 nm-1.5 μm and a uniform size distribution, and a specific surface area of ​​387 m². 2 / g.

[0070] from Figure 5 It can be seen that the products obtained in Comparative Examples 1 and 2 are non-bismuth-based metal-organic framework materials. The reason for this result is that during the ball milling process, the conversion of mechanical energy into chemical energy or other forms of energy requires a certain amount of time to accumulate. If the rotation speed is too low, the rate of energy transfer and accumulation will be slow, which will not meet the energy conditions (especially temperature) required for sample preparation, thus affecting the formation of products.

[0071] Experimental Example 1

[0072] The sheet-like bismuth-based organic framework material prepared in Example 1 was used as an adsorbent for dye adsorption.

[0073] Specific steps: 1) Dissolve 10 mg of the bismuth-based metal-organic framework material prepared in Example 1 in 20 ml of 100 mg / L Rhodamine B (RhB) solution. The suspension is magnetically stirred. Every 15 minutes, approximately 1 mL of the suspension is extracted using a syringe and passed through a 0.22 μm polytetrafluoroethylene syringe filter to completely remove the adsorbed powder. The remaining concentration of RhB is analyzed using UV-Vis spectroscopy (characteristic absorption peak of RhB at 554 nm), and the adsorption curve of RhB is obtained. Results are shown below. Figure 6 .

[0074] Depend on Figure 6 It is known that sheet-like bismuth-based organic framework materials can reduce the RhB concentration from 100 ml / L to 5 mg / L, with a removal rate of more than 95%.

[0075] The above results demonstrate that the sheet-like bismuth-based metal-organic framework material prepared in this invention exhibits a significantly different microstructure compared to the rod-shaped CAU-17. The obtained sheet-like bismuth-based organic framework material demonstrates excellent adsorption performance when used to adsorb RhB, thus making it a potential candidate material for highly efficient dye adsorbents.

[0076] Meanwhile, the sheet-like bismuth-based metal-organic framework material prepared in Example 1 was subjected to electrochemical carbon dioxide reduction testing, and the main product was formic acid. Specific results are shown in [link to results]. Figure 7 .

[0077] Depend on Figure 7 The results show that, under the conditions of -0.9V vs RHE, the selectivity of formic acid in the electrocatalytic reduction products of carbon dioxide by the sheet-like bismuth-based metal-organic framework material is greater than 90%, indicating high performance.

[0078] This invention is not limited to the specific embodiments described above. Any modifications made by those skilled in the art based on the above concept without creative effort are within the scope of protection of this invention.

Claims

1. A method for preparing a sheet-like bismuth-based metal-organic framework material, characterized in that, Includes the following steps: S1. Mix bismuth salt and polybasic acid organic ligand to obtain a mixture; S2. The obtained mixture is mixed with grinding balls and ball-milled to obtain a bismuth-based metal-organic framework material; The ball milling process is carried out at room temperature, the ball milling speed is 500-5000 rpm / min, and the ball milling time is 0.5min-10min.

2. The method for preparing the sheet-like bismuth-based metal-organic framework material according to claim 1, characterized in that, During the ball milling process, a ball milling auxiliary solvent is added to accelerate the reaction.

3. The method for preparing the sheet-like bismuth-based metal-organic framework material according to claim 1, characterized in that, The grinding balls used in the ball milling process are zirconium oxide balls; the ratio of the total mass of the bismuth salt and the polybasic acid organic ligand to the total mass of the grinding balls is 1:10-20.

4. The method for preparing the sheet-like bismuth-based metal-organic framework material according to claim 1, characterized in that, The mass ratio of the bismuth salt to the polybasic acid organic ligand is 1:1-10.

5. The method for preparing the sheet-like bismuth-based metal-organic framework material according to claim 1, characterized in that, The bismuth salt is one or a combination of two or more of bismuth nitrate pentahydrate, bismuth acetate, and bismuth oxynitrate.

6. The method for preparing the sheet-like bismuth-based metal-organic framework material according to claim 1, characterized in that, The polybasic acid organic ligand is one or a combination of two or more of 1,3,5-pyromellitic acid, triazine-2,4,6-trimethyl-tribenzoic acid, and biphenyl-3,3',5,5'-tetracarboxylic acid.

7. The method for preparing the sheet-like bismuth-based metal-organic framework material according to claim 2, characterized in that, The ball milling auxiliary solvent is one or a combination of two or more of methanol, ethanol, DMF, and 1,2-propanediol.

8. A sheet-like bismuth-based metal-organic framework material obtained by the preparation method according to any one of claims 1-7.

9. The application of the sheet-like bismuth-based metal-organic framework material as described in claim 8 in carbon dioxide adsorption and reduction and pollutant adsorption in water.

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