Preparation method and application of amorphous hollow tube spherical bismuth tungstate material

Abstract

This invention relates to a method for preparing and applying amorphous hollow tubular spherical bismuth tungstate materials. The method involves adding bismuth salt, a polybasic acid organic ligand, and a nonionic surfactant to a methanol-water binary solvent and reacting the mixture at room temperature to obtain a bismuth-based metal-organic framework as the bismuth source material. A soluble tungstate is dissolved in deionized water, and a dispersant is added to obtain solution A. The bismuth-based metal-organic framework is then mixed with ethylene glycol to obtain solution B. Under stirring, solution A is added dropwise to solution B, and the mixture is stirred to obtain a precursor solution. The precursor solution undergoes a hydrothermal reaction, followed by centrifugation and drying to obtain amorphous hollow tubular spherical bismuth tungstate. The advantages of this invention are: the prepared amorphous hollow tubular spherical bismuth tungstate exhibits superior photocatalytic performance; the raw materials used are non-toxic and harmless, enabling rapid synthesis while reducing energy consumption; and the raw material composition is simple, and the process is simple and controllable.

Description

Technical Field

[0001] This invention relates to the synthesis of organic-inorganic hybrid materials and their derivatives for use in the field of photocatalysis, particularly a method for preparing and applying an amorphous hollow tube-shaped spherical bismuth tungstate material. Background Technology

[0002] Bismuth tungstate is typically a perovskite-type inorganic metal oxide. It belongs to the tetragonal crystal system and is formed by alternating layers of [WO6] octahedra and [Bi2O2], exhibiting a stable porous structure. Among a range of bismuth-based inorganic compounds, bismuth tungstate is recognized as a novel photocatalyst with a narrow bandgap and visible light response, capable of absorbing visible light energy to degrade organic pollutants.

[0003] Metal-organic frameworks (MOFs) are one-dimensional, two-dimensional, or three-dimensional organic-inorganic hybrid materials formed by coordination bonds between organic ligands and metal ions or metal ion clusters. Thanks to their large specific surface area and abundant porous structures, MOFs have broad application prospects in adsorption, catalysis, batteries, sensing, and energy storage.

[0004] In metal-organic frameworks (MOFs), transition metals dominate the network chemistry, followed by rare earth cations and other main group cations. Bismuth, a relatively rare heavy metal, is safer for biological use than other toxic heavy metals, and its diverse coordination structures and low cost make it a promising candidate for a wide range of applications.

[0005] Bismuth-based metal-organic framework (MOF) derivatives are typically prepared via methods such as pyrolysis or chemical treatment. These derivatives inherit some properties of bismuth-based MOFs while potentially exhibiting novel functionalities. Various bismuth-based nanostructures derived from bismuth-based MOFs through thermal conversion and in-situ chemical transformation have been widely used as electrocatalysts, photocatalysts, and electrode materials.

[0006] However, existing bismuth tungstate photocatalysts have practical problems such as poor absorption of visible light, easy recombination of photogenerated electrons and holes during migration, and easy photocorrosion or structural deactivation of bismuth tungstate under long-term light exposure or treatment of high-concentration pollutants. Summary of the Invention

[0007] The purpose of this invention is to address the shortcomings of the prior art by providing a method for preparing and applying an amorphous hollow tube spherical bismuth tungstate material. Using a bismuth-based metal-organic framework as the matrix, an amorphous hollow tube spherical bismuth tungstate photocatalyst is synthesized through chemical treatment. This photocatalyst has a large specific surface area of ​​catalytic active sites, and its amorphous structure endows the material with excellent catalytic ability.

[0008] The objective of this invention is achieved through the following technical solutions: A method for preparing an amorphous hollow tubular spherical bismuth tungstate material, characterized in that the preparation method includes the following steps: Bismuth salts, polybasic acid organic ligands, and nonionic surfactants were added to a binary solvent of methanol and water, and the mixture was stirred at room temperature to obtain a bismuth-based metal-organic framework as a bismuth source material. Soluble tungstate is dissolved in deionized water, and a dispersant is added to obtain solution A; the bismuth-based metal-organic framework is mixed with ethylene glycol to obtain solution B; under stirring, solution A is added dropwise to solution B and stirred to obtain precursor solution; The precursor solution was subjected to a hydrothermal reaction, and after the reaction was completed, it was centrifuged and dried to obtain amorphous hollow tube-shaped spherical bismuth tungstate.

[0009] The bismuth salt is bismuth nitrate pentahydrate; the polybasic acid organic ligand is 1,3,5-benzenetricarboxylic acid; and the nonionic surfactant is polyether F127.

[0010] The mass ratio of the bismuth salt to the nonionic surfactant is 30:1-6:1; the volume ratio of methanol to water in the mixed solvent of methanol and water is 6:1-2:1.

[0011] The volume ratio of deionized water in solution A to ethylene glycol in solution B is 1:1 to 1:5; the mass ratio of dispersant in solution A to bismuth-based metal-organic framework in solution B is 1:1 to 1:6; the molar amount of soluble tungstate added to solution A is 0.05 mmol to 0.2 mmol; and the stirring time is 10 min to 30 min.

[0012] The dispersant is one or a combination of two or more of polyethylene glycol, polyacrylic acid, polyvinylpyrrolidone, and sodium dodecyl sulfate; the soluble tungstate is one or a combination of two or more of calcium tungstate, sodium tungstate dihydrate, and cobalt tungstate.

[0013] The hydrothermal reaction temperature is 120℃-180℃, and the reaction time is 2h-10h.

[0014] An application of a method for preparing the above-mentioned amorphous hollow tube spherical bismuth tungstate material is characterized in that: the prepared amorphous hollow tube spherical bismuth tungstate material is used as a photocatalytic material in the catalytic gas formaldehyde.

[0015] An application of a method for preparing the above-mentioned amorphous hollow tube spherical bismuth tungstate material is characterized in that: the prepared amorphous hollow tube spherical bismuth tungstate material is used as a photocatalytic material in the degradation of Rhodamine B.

[0016] The advantages of this invention are: (1) By utilizing the effect of surfactants, spiky bismuth-based metal-organic frameworks can be prepared quickly and easily as precursors, giving bismuth tungstate a unique morphology.

[0017] (2) The prepared bismuth tungstate has a unique hollow tube spherical morphology, which increases its specific surface area, has good adsorption of organic pollutants, and enhances the photocatalytic reaction sites.

[0018] (3) The prepared bismuth tungstate has a unique amorphous structure and the appearance of unsaturated defect sites promotes the catalytic reaction.

[0019] (4) It has the characteristics of simple process, controllability and low cost, and is suitable for large-scale synthesis. Attached Figure Description

[0020] Figure 1 These are scanning electron microscope images of bismuth-based metal-organic framework materials prepared in any embodiment of the present invention; Figure 2 The X-ray diffraction pattern of the bismuth-based metal-organic framework material obtained in any embodiment of the present invention is shown below. Figure 3 Scanning electron microscope image of the amorphous hollow tube spherical bismuth tungstate obtained in Example 2 of this invention; Figure 4 Scanning electron microscope image of nano-flower-shaped bismuth tungstate prepared in Comparative Example 1 provided by the present invention; Figure 5 X-ray diffraction pattern of amorphous hollow tube spherical bismuth tungstate obtained in Example 2 of this invention; Figure 6 Transmission electron microscope image of the amorphous hollow tube spherical bismuth tungstate obtained in Example 2 of this invention; Figure 7 The amorphous hollow tube spherical bismuth tungstate prepared in Example 2 of this invention and the bismuth tungstate synthesized by the conventional solvothermal method are used as photocatalysts for the degradation of Rhodamine B under visible light, respectively. Detailed Implementation

[0021] The features and other related features of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments, so as to facilitate understanding by those skilled in the art: Example 1: The preparation method of the amorphous hollow tube spherical bismuth tungstate in this example includes the following steps: 1) Dissolve 10 mg of polyether block copolymer F127 in 25 mL of methanol-water mixture (V MeOH :V H2OIn a mixture of 4:1, the solution was stirred to obtain a clear, transparent, colorless solution. 100 mg of bismuth nitrate pentahydrate and 700 mg of 1,3,5-pyromellitic acid were added to the obtained clear, transparent, colorless solution. The mixture was stirred evenly and stirred at room temperature for 90 min at 1500 rpm to obtain a white emulsion. The obtained white emulsion was washed with methanol solution by centrifugation and discarding the supernatant. The washing process was repeated three times, and the precipitate was collected and vacuum activated overnight in a vacuum drying oven at 70°C to obtain a bismuth-based metal-organic framework material as the bismuth tungstate matrix.

[0022] 2) Dissolve 300 mg of the prepared bismuth-based metal-organic framework material in 40 mL of ethylene glycol and stir at room temperature for 30 min; this is solution A. Dissolve 150 mg of the dispersant polyvinylpyrrolidone in 30 mL of deionized water and add 16.6 mg of sodium tungstate dihydrate; this is solution B. While stirring, slowly add solution B dropwise to solution A and stir thoroughly.

[0023] 3) The mixture was placed in a reaction vessel for hydrothermal reaction for 5 hours at a temperature of 160°C. After the reaction, the solid was separated by centrifugation, washed three times with anhydrous ethanol and deionized water respectively, and then vacuum activated overnight in a vacuum drying oven at 70°C to obtain amorphous hollow tube spherical bismuth tungstate material, which is called AC-BWO-1.

[0024] Example 2: The preparation method of the amorphous hollow tube spherical bismuth tungstate in this example includes the following steps: 1) Dissolve 10 mg of polyether block copolymer F127 in 25 mL of methanol-water mixture (V MeOH :V H2O In a mixture of 4:1, the solution was stirred to obtain a clear, transparent, colorless solution. 100 mg of bismuth nitrate pentahydrate and 700 mg of 1,3,5-pyromellitic acid were added to the obtained clear, transparent, colorless solution. The mixture was stirred evenly and stirred at room temperature for 90 min at 1500 rpm to obtain a white emulsion. The obtained white emulsion was washed with methanol solution by centrifugation and discarding the supernatant. The washing process was repeated three times, and the precipitate was collected and vacuum activated overnight in a vacuum drying oven at 70°C to obtain a bismuth-based metal-organic framework material as the bismuth tungstate matrix.

[0025] 2) Dissolve 300 mg of the prepared bismuth-based metal-organic framework material in 40 mL of ethylene glycol and stir at room temperature for 30 min; this is solution A. Dissolve 150 mg of the dispersant polyvinylpyrrolidone in 30 mL of deionized water and add 32.9 mg of sodium tungstate dihydrate; this is solution B. While stirring, slowly add solution B dropwise to solution A and stir thoroughly.

[0026] 3) The mixture was placed in a reaction vessel for hydrothermal reaction for 5 hours at a temperature of 160°C. After the reaction, the solid was separated by centrifugation, washed three times with anhydrous ethanol and deionized water respectively, and then vacuum activated overnight in a vacuum drying oven at 70°C to obtain amorphous hollow tube spherical bismuth tungstate material, which is called AC-BWO-2.

[0027] Example 3: The preparation method of the amorphous hollow tube spherical bismuth tungstate in this example includes the following steps: 1) Dissolve 10 mg of polyether block copolymer F127 in 25 mL of methanol-water mixture (V MeOH :V H2O In a mixture of 4:1, the solution was stirred to obtain a clear, transparent, colorless solution. 100 mg of bismuth nitrate pentahydrate and 700 mg of 1,3,5-pyromellitic acid were added to the obtained clear, transparent, colorless solution. The mixture was stirred evenly and stirred at room temperature for 90 min at 1500 rpm to obtain a white emulsion. The obtained white emulsion was washed with methanol solution by centrifugation and discarding the supernatant. The washing process was repeated three times, and the precipitate was collected and vacuum activated overnight in a vacuum drying oven at 70°C to obtain a bismuth-based metal-organic framework material as the bismuth tungstate matrix.

[0028] 2) Dissolve 300 mg of the prepared bismuth-based metal-organic framework material in 40 mL of ethylene glycol and stir at room temperature for 30 min; this is solution A. Dissolve 150 mg of the dispersant polyvinylpyrrolidone in 30 mL of deionized water and add 42.8 mg of sodium tungstate dihydrate; this is solution B. While stirring, slowly add solution B dropwise to solution A and stir thoroughly.

[0029] 3) The mixture was placed in a reaction vessel for hydrothermal reaction for 5 hours at a temperature of 160°C. After the reaction, the solid was separated by centrifugation, washed three times with anhydrous ethanol and deionized water respectively, and then vacuum activated overnight in a vacuum drying oven at 70°C to obtain amorphous hollow tube spherical bismuth tungstate material, which is called AC-BWO-3.

[0030] Example 4: The preparation method of the amorphous hollow tube spherical bismuth tungstate in this example includes the following steps: 1) Dissolve 10 mg of polyether block copolymer F127 in 25 mL of methanol-water mixture (V MeOH :V H2OIn a mixture of 4:1, the solution was stirred to obtain a clear, transparent, colorless solution. 100 mg of bismuth nitrate pentahydrate and 700 mg of 1,3,5-pyromellitic acid were added to the obtained clear, transparent, colorless solution. The mixture was stirred evenly and stirred at room temperature for 90 min at 1500 rpm to obtain a white emulsion. The obtained white emulsion was washed with methanol solution by centrifugation and discarding the supernatant. The washing process was repeated three times, and the precipitate was collected and vacuum activated overnight in a vacuum drying oven at 70°C to obtain a bismuth-based metal-organic framework material as the bismuth tungstate matrix.

[0031] 2) Dissolve 300 mg of the prepared bismuth-based metal-organic framework material in 40 mL of ethylene glycol and stir at room temperature for 30 min; this is solution A. Dissolve 150 mg of the dispersant polyvinylpyrrolidone in 30 mL of deionized water and add 56.6 mg of sodium tungstate dihydrate; this is solution B. While stirring, slowly add solution B dropwise to solution A and stir thoroughly.

[0032] 3) The mixture was placed in a reaction vessel for hydrothermal reaction for 5 hours at a temperature of 160°C. After the reaction, the solid was separated by centrifugation, washed three times with anhydrous ethanol and deionized water respectively, and then vacuum activated overnight in a vacuum drying oven at 70°C to obtain amorphous hollow tube spherical bismuth tungstate material, which is called AC-BWO-4.

[0033] Example 5: The preparation method of the amorphous hollow tube spherical bismuth tungstate in this example includes the following steps: 1) Dissolve 10 mg of polyether block copolymer F127 in 25 mL of methanol-water mixture (V MeOH :V H2O In a mixture of 4:1, the solution was stirred to obtain a clear, transparent, colorless solution. 100 mg of bismuth nitrate pentahydrate and 700 mg of 1,3,5-pyromellitic acid were added to the obtained clear, transparent, colorless solution. The mixture was stirred evenly and stirred at room temperature for 90 min at 1500 rpm to obtain a white emulsion. The obtained white emulsion was washed with methanol solution by centrifugation and discarding the supernatant. The washing process was repeated three times, and the precipitate was collected and vacuum activated overnight in a vacuum drying oven at 70°C to obtain a bismuth-based metal-organic framework material as the bismuth tungstate matrix.

[0034] 2) Dissolve 300 mg of the prepared bismuth-based metal-organic framework material in 40 mL of ethylene glycol and stir at room temperature for 30 min; this is solution A. Dissolve 150 mg of the dispersant polyvinylpyrrolidone in 30 mL of deionized water and add 65.9 mg of sodium tungstate dihydrate; this is solution B. While stirring, slowly add solution B dropwise to solution A and stir thoroughly.

[0035] 3) The mixture was placed in a reaction vessel for hydrothermal reaction for 5 hours at a temperature of 160°C. After the reaction, the solid was separated by centrifugation, washed three times with anhydrous ethanol and deionized water respectively, and then vacuum activated overnight in a vacuum drying oven at 70°C to obtain amorphous hollow tube spherical bismuth tungstate material, which is called AC-BWO-5.

[0036] Comparative Example 1: This Comparative Example 1 compares the nano-flower-shaped bismuth tungstate with the amorphous hollow tube spherical bismuth tungstate material prepared in the above examples. The preparation method of the nano-flower-shaped bismuth tungstate includes the following steps: 1) Dissolve 300 mg of bismuth nitrate pentahydrate in 40 mL of ethylene glycol and stir at room temperature for 30 min; this is solution A. Dissolve 150 mg of the dispersant polyvinylpyrrolidone in 30 mL of deionized water and add 67.5 mg of sodium tungstate dihydrate; this is solution B. While stirring, slowly add solution B dropwise to solution A and stir thoroughly.

[0037] 2) The mixture was placed in a reaction vessel for hydrothermal reaction for 5 hours at a temperature of 160°C. After the reaction, the solid was separated by centrifugation, washed three times with anhydrous ethanol and deionized water respectively, and then vacuum activated overnight in a vacuum drying oven at 70°C to obtain the traditional nano-flower-shaped bismuth tungstate material, which is called BWO.

[0038] 1. Scanning electron microscopy (SEM) test: The microstructure of the prepared samples was characterized using SEM, and the results are shown in the figure. Figure 1 , Figure 3 and Figure 4 , Figure 1 The bismuth-based metal-organic framework material prepared in any of the embodiments. Figure 3 For AC-BWO-2, Figure 4 It is BWO.

[0039] Depend on Figure 1 (a) The results show that the morphology of the prepared bismuth-based metal-organic framework structure is spiky, with a diameter of about 2 μm.

[0040] Depend on Figure 1 (b) The results show that the prepared bismuth-based metal-organic framework material is self-assembled from a rod-like structure. This radial morphology from the inside out endows the bismuth-based metal-organic framework material with richer pore size and better specific surface area, and also provides more active sites for subsequent chemical conversion into photocatalyst.

[0041] Depend on Figure 4The results show that the BWO prepared by Comparative Example 1 has a nanoflower-like structure composed of nanosheets, which has a similar morphology to the traditional bismuth tungstate reported in the literature. The nanoflower-like structure endows the material with good catalytic active sites.

[0042] Depend on Figure 3 The results show that the AC-BWO prepared in Example 2 is composed of hollow nanorods. In addition to retaining the parent CAU-17 spiky structure, it has a hollow cavity structure inside. This unique hollow tube spherical bismuth tungstate photocatalytic material can endow the material with a huge specific surface area and provide more active sites for subsequent photocatalytic degradation of formaldehyde and Rhodamine B.

[0043] 2. X-ray diffraction (XRD) test: The prepared sample was subjected to X-ray diffraction analysis, and the test results are shown in the figure. Figure 2 and Figure 5 , Figure 2 The bismuth-based metal-organic framework materials prepared in any of the embodiments are shown. Figure 5 AC-BWO-2 prepared in Example 2.

[0044] Depend on Figure 2 The results show that the prepared bismuth-based metal-organic framework material has good crystallinity and exhibits diffraction peaks unique to bismuth-based metal-organic framework materials in the diffraction angle range of 5°-30°. Furthermore, the positions of all diffraction peaks of this 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 this bismuth-based metal-organic framework material has the same crystal structure as CAU-17. That is, the spiky bismuth-based metal-organic framework material prepared in this invention is CAU-17.

[0045] from Figure 5 As can be seen, the prepared AC-BWO-2 material does not exhibit a sharp characteristic peak at 10°, proving that all the material after chemical derivatization of the metal-organic framework was converted into BWO, with no metal-organic framework material residue. The prepared material exhibits a broad peak at 28°-32°, which matches the characteristic peak of the bismuth tungstate standard card; this broadened "bun peak" confirms the synthesis of amorphous bismuth tungstate.

[0046] 3. Transmission electron microscopy (TEM) testing: The microstructure of the prepared sample was characterized using TEM, and the test results are shown in the figure. Figure 6 , Figure 6 AC-BWO-2 prepared in Example 2.

[0047] Figure 6As can be seen from the transmission spectrum, the bismuth tungstate material prepared in Example 2 has no visible lattice fringes, and the electron diffraction (SAED) pattern also shows a wide diffraction ring, which further illustrates that the bismuth tungstate material obtained in Example 2 has an amorphous bismuth tungstate structure.

[0048] 4. Evaluate the photocatalytic performance of the photocatalyst: (1) Photocatalytic degradation performance test of formaldehyde: Amorphous hollow tubular spherical bismuth tungstate photocatalyst material was used for the degradation of gaseous formaldehyde. The application method was as follows: 200 mg of the amorphous hollow tubular spherical bismuth tungstate photocatalyst material was evenly distributed in a petri dish, placed in a Tedlar gas bag, and 4 μL of formaldehyde solution was injected. 4 L of fresh air was then introduced, and the gas bag was placed in a 60℃ oven and heated for 30 min to ensure complete vaporization. The entire degradation process was first carried out under dark conditions for 1.5 h of dark adsorption. A xenon lamp equipped with a 420 nm cutoff filter was used for photocatalytic reaction. 5 mL of gas was collected from the gas bag every 30 min, and the formaldehyde concentration was detected using phenol reagent spectrophotometry. The formaldehyde removal rate was calculated using the following formula, indicating the formaldehyde degradation performance of the reaction catalyst material.

[0049] Removal efficiency (%) = (C 0- C) / C0×100% Where C0 is the concentration of gaseous pollutants at adsorption equilibrium, in ppm; C is the concentration of gaseous pollutants at each sampling, in ppm. The test results are shown in Table 1.

[0050] As shown in Table 1, formaldehyde hardly degrades under blank conditions. The formaldehyde degradation rate of traditional nano-flower-shaped bismuth tungstate photocatalyst is only 24% after 4 hours of light irradiation. The amorphous hollow tube spherical bismuth tungstate photocatalyst material derived from bismuth-based metal-organic frameworks achieves a significantly improved formaldehyde degradation rate of up to 86%. This is due to the amorphous crystal structure and the unique hollow tube spherical morphology that endow it with huge active sites. The two work synergistically to achieve a highly efficient formaldehyde degradation ability.

[0051] Table 1

[0052] (2) Performance test of photocatalytic degradation of Rhodamine B: Rhodamine B was degraded by photocatalysis under visible light. Specific steps: A 300 W xenon lamp was used as the light source; the photocatalytic reactor was placed to the left of the xenon lamp, with the reaction interface 15 cm from the light source; the light intensity was 300 mW·cm². -2 The experimental setup was kept in a closed environment to eliminate interference from external light sources, ensuring the reliability and authenticity of the experimental data. In the photocatalysis experiment, 25 mL of Rhodamine B solution (50 mg / L) was used.-1 10 mg of catalyst was added to a glass bottle. Before light exposure, the suspension was magnetically stirred in the dark for 30 min to allow the catalyst and Rhodamine B to reach adsorption-desorption equilibrium. Then, the solution was exposed to a light source, and the reaction was initiated with magnetic stirring. Every 30 minutes, approximately 1 mL of the suspension was extracted using a syringe and passed through a 0.22 μm PTFE syringe filter to completely remove the catalyst powder. The remaining concentration of Rhodamine B was analyzed using UV-Vis spectroscopy (the characteristic absorption peak of Rhodamine B at 554 nm), and the photocatalytic degradation curve of Rhodamine B was obtained. Specific results are shown in [link to results]. Figure 7 .

[0053] Depend on Figure 7 The results showed that the amorphous hollow tube spherical bismuth tungstate material, as a photocatalyst, achieved a degradation rate of up to 99.5% after 2 hours of photocatalytic degradation of 25 mL of 50 ppm Rhodamine B aqueous solution, while the degradation rate of nano-flower-shaped bismuth tungstate synthesized by the traditional solvothermal method was only 77%.

[0054] The above results demonstrate that the amorphous hollow tubular spherical bismuth tungstate material prepared in this invention exhibits a distinctly different microstructure. The amorphous bismuth tungstate displays excellent photoresponse performance, and compared to bismuth tungstate material directly prepared from bismuth pentahydrate and sodium tungstate dihydrate via a hydrothermal method, the amorphous hollow tubular spherical bismuth tungstate exhibits superior photocatalytic degradation performance. Therefore, the amorphous hollow tubular spherical bismuth tungstate material prepared in this invention can serve as a high-performance photocatalyst for the degradation of organic pollutants.

[0055] Although the above embodiments have described the concept and embodiments of the present invention in detail with reference to the accompanying drawings, those skilled in the art will recognize that various improvements and modifications can still be made to the present invention without departing from the scope of the claims, and therefore will not be elaborated here.

Claims

1. A method for preparing an amorphous hollow tubular spherical bismuth tungstate material, characterized in that: The preparation method includes the following steps: Bismuth salts, polybasic acid organic ligands, and nonionic surfactants were added to a binary solvent of methanol and water, and the mixture was stirred at room temperature to obtain a spiky bismuth-based metal-organic framework as a bismuth source material. Soluble tungstate is dissolved in deionized water, and a dispersant is added to obtain solution A; the spiky bismuth-based metal-organic framework is mixed with ethylene glycol to obtain solution B; under stirring, solution A is added dropwise to solution B and stirred to obtain precursor solution; The precursor solution was subjected to a hydrothermal reaction, and after the reaction was completed, it was centrifuged and dried to obtain amorphous hollow tube-shaped spherical bismuth tungstate. The bismuth salt is bismuth nitrate pentahydrate; the polybasic acid organic ligand is 1,3,5-benzenetricarboxylic acid; and the nonionic surfactant is polyether F127. The mass ratio of the bismuth salt to the nonionic surfactant is 30:1-6:1; the volume ratio of methanol to water in the mixed solvent of methanol and water is 6:1-2:

1. The hydrothermal reaction temperature is 120℃-180℃, and the reaction time is 2h-10h.

2. The method for preparing an amorphous hollow tubular spherical bismuth tungstate material according to claim 1, characterized in that: The volume ratio of deionized water in solution A to ethylene glycol in solution B is 1:1 to 1:5; the mass ratio of dispersant in solution A to bismuth-based metal-organic framework in solution B is 1:1 to 1:6; and the molar amount of soluble tungstate added to solution A is 0.05 mmol to 0.2 mmol.

3. The method for preparing an amorphous hollow tubular spherical bismuth tungstate material according to claim 1, characterized in that: The dispersant is one or a combination of two or more of polyethylene glycol, polyacrylic acid, polyvinylpyrrolidone, and sodium dodecyl sulfate; the soluble tungstate is one or a combination of two or more of calcium tungstate, sodium tungstate dihydrate, and cobalt tungstate.

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