A BiO 2-x Energy storage catalysts, methods of making and using same

Abstract

The application provides a BiO 2‑x Energy storage catalyst, preparation method and application thereof, the preparation method comprises the following steps: step 1, NaBiO3·2H2O powder is added to NaOH solution, stirring, and a sodium bismuthate alkali solution is obtained; wherein the molar ratio of NaBiO3·2H2O to NaOH is (0.045-0.18):(2-4); step 2, the sodium bismuthate alkali solution is added dropwise into water, stirring, and a reaction precursor solution is obtained; step 3, the reaction precursor solution is subjected to hydrothermal reaction at 160-180 DEG C, and the obtained reaction product is washed and dried to obtain BiO 2‑x Energy storage catalyst. The BiO 2‑x Catalyst prepared by the method has piezoelectric characteristics, and has good broad-spectrum cyclic degradation effect on antibiotics, organic matters and dyes under dark conditions.

Description

Technical Field

[0001] This invention belongs to the field of piezoelectric energy storage catalytic material preparation technology, specifically a BiO2 material. 2-x Energy storage catalysts, their preparation methods, and applications. Background Technology

[0002] Currently, the discharge of industrial wastewater from antibiotic and synthetic dye industries poses a serious threat to the environment. The persistent presence of tetracycline in the environment not only contributes to the development of antibiotic-resistant bacteria but also leads to the accumulation of biotoxicity, exerting subtle influences on ecosystems and humans. Photocatalysis has enormous potential in addressing the energy crisis and mitigating environmental pollution. Due to its environmental friendliness, high degradation efficiency, and stable performance, photocatalysis technology has attracted considerable attention and research. However, the diffuse and geographically specific nature of sunlight limits its application. Traditional photocatalysis cannot purify industrial wastewater from antibiotic and synthetic dye industries under dark conditions. Therefore, piezoelectric energy storage catalytic materials with catalytic activity under dark conditions represent a potential method for effectively degrading industrial wastewater with low light transmittance.

[0003] BiO 2-x BiO is a non-toxic, structurally stable, and easily synthesized bismuth-based semiconductor in which uniformly dispersed Bi-6s orbitals facilitate carrier migration and narrow band gap. As a narrow-bandgap (<2 eV) layered material, it exhibits excellent light absorption in the ultraviolet-visible-near-infrared range and even in the infrared, making it one of the most attractive photocatalysts for the full-spectrum degradation of organic environmental pollutants. However, currently, there is no BiO2 suitable photocatalyst. 2-x Application reports of catalysts in degrading organic environmental pollutants under dark conditions. Summary of the Invention

[0004] To address the problems existing in the prior art, the present invention provides a BiO 2-x Energy storage catalyst, its preparation method and application, wherein the BiO obtained by the preparation method 2-x The catalyst has piezoelectric properties and exhibits good broad-spectrum cyclic degradation of antibiotics, organic matter, and dyes under dark conditions.

[0005] This invention is achieved through the following technical solution:

[0006] A BiO 2-x The preparation method of the energy storage catalyst includes the following steps:

[0007] Step 1: Add NaBiO3·2H2O powder to NaOH solution and stir to obtain sodium bismuthate alkaline solution; wherein, the molar ratio of NaBiO3·2H2O to NaOH is (0.045~0.18):(2~4);

[0008] Step 2: Add sodium bismuthate alkaline solution dropwise to water and stir to obtain the reaction precursor solution;

[0009] Step 3: The precursor solution undergoes a hydrothermal reaction at 160℃~180℃. The resulting reaction product is washed and dried to obtain BiO. 2-x Energy storage catalyst.

[0010] Preferably, in step 1, the concentration of the NaOH solution is 2 mol / L to 4 mol / L.

[0011] Preferably, in step 2, the stirring time is 20 min to 120 min.

[0012] Preferably, in step 3, the hydrothermal reaction time is 30 min to 120 min.

[0013] Preferably, in step 3, the washing process specifically involves: first, centrifuging with deionized water until the pH of the resulting supernatant is 6.5-7, and then washing multiple times with anhydrous ethanol.

[0014] Preferably, in step 3, the drying process specifically involves vacuum drying at 65℃~75℃.

[0015] The present invention also provides a BiO prepared by the method described above. 2-x Energy storage catalyst, the BiO 2-x The energy storage catalyst is a cubic phase with a space group of Fm-3m, and BiO 2-x Energy storage catalysts store electrons and holes.

[0016] The present invention provides the BiO 2-x Application of energy storage catalysts in the catalytic degradation of organic pollutants under dark conditions.

[0017] Preferably, the organic pollutant is an antibiotic or a dye.

[0018] The present invention also provides the BiO 2-x Application of energy storage catalysts in the catalytic degradation of organic pollutants.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] This invention BiO 2-x The preparation method of the energy storage catalyst involves adding NaBiO3·2H2O powder to a NaOH solution, where only BiO3 can exist in the solution. - and Na + The sodium bismuthate solution could not be further hydrolyzed. Sodium bismuthate alkaline solution was added dropwise to water, and the added BiO3... - With H +Rapidly combines to form uniformly sized HBiO3·BiO3 in the solution. - Colloidal particles, uniform colloidal particles, partially Bi during hydrothermal reaction 5+ Restore Bi 3+ To bind a cavity in Bi 3+ Around the crystal, oxygen escapes and forms O2, causing oxygen deficiency inside the crystal (HBiO3·BiO3 + H2O → 2BiO). 2-x +O2↑+H + The excess electrons formed by oxygen vacancies contribute to the formation of BiO. 2-x Nanocrystals, under hydrothermal high-temperature conditions, dissolve and crystallize to grow into tetragonal nanosheets and nanorods. The short hydrothermal dissolution and crystallization process (30-120 minutes) prevents the elimination of oxygen vacancies in the crystals; therefore, oxygen vacancies and Bi2O3 coexist in both the tetragonal nanosheets and nanorods. 3+ / Bi 5+ To balance the total valence of the crystal, tetragonal nanosheets and nanorods of BiO2... 2-x Crystal lattice displacement generates a piezoelectric polarization field. The tetragonal nanosheet and nanorod morphologies further facilitate the release of piezoelectric charges. This is due to oxygen vacancies and Bi... 3+ / Bi 5+ The existence of a polarization electric field inside the crystal, BiO 2-x Energy storage catalysts simultaneously store a large number of electrons and holes. BiO₂ under dark conditions... 2-x Mechanical stress disturbance induces strain, which enhances the piezoelectric polarization field of the crystal. Under dark conditions, stored holes and vacancies are rapidly released to catalyze the reaction. Simultaneously, the mechanical stress disturbance strain causes BiO 2-x The energy storage catalyst generates piezoelectric charges, which are then released to continuously degrade organic pollutants.

[0021] The BiO of the present invention 2-x Energy storage catalysts, due to the coexistence of oxygen vacancies and Bi in the crystal, 3+ / Bi 5+ To enable tetragonal nanosheets and nanorods BiO 2-x Crystal lattice displacement generates a piezoelectric polarization field, which is observed in tetragonal nanosheets and nanorods of BiO under dark conditions. 2-x The release of stored charges and the formation of piezoelectric charges exhibit high degradation efficiency for antibiotics such as tetracycline and ciprofloxacin, organic compounds such as bisphenol A, and dyes such as methylene blue and methylene orange, and also demonstrate good cycling stability under dark conditions. BiO 2-x The method of purifying water pollution under dark conditions using energy storage catalysts has promising applications. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the examples of the present invention or the prior art, the drawings used in the description of the examples or the prior art will be briefly introduced below. Obviously, the drawings described below are some examples of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0023] Figure 1 These are XRD patterns of the catalysts prepared in Examples 1, 2 and 5 of this invention.

[0024] Figure 2 These are Raman diagrams of the catalysts prepared in Examples 1, 2 and 5 of this invention.

[0025] Figure 3 This is a SEM image of the catalyst prepared in Example 1 of this invention.

[0026] Figure 4 This is an HRTEM image of the catalyst prepared in Example 1 of the present invention.

[0027] Figure 5 This is the absorbance curve of the catalyst prepared in Example 1 of the present invention for 20 mg / L methylene blue under dark conditions.

[0028] Figure 6 The catalyst prepared in Example 1 of this invention under dark conditions h + The electron paramagnetic resonance spectrum.

[0029] Figure 7 This is a PFM phase change diagram of the catalyst prepared in Example 1 of the present invention.

[0030] Figure 8 This is a graph showing the PFM amplitude variation of the catalyst prepared in Example 1 of this invention.

[0031] Figure 9 This is a current diagram of the catalyst prepared in Example 1 of the present invention under dark conditions.

[0032] Figure 10 This describes the degradation performance of the catalysts prepared in Examples 1, 2, and 5 of this invention on 20 mg / L tetracycline under dark conditions.

[0033] Figure 11 The removal rate of 40 mg / L tetracycline TOC by the catalysts prepared in Examples 1, 2 and 5 of this invention under dark conditions.

[0034] Figure 12 This is the mass spectrum of the catalyst prepared in Example 1 of this invention during the degradation of 20 mg / L tetracycline for 10 min under dark conditions, and the mass-to-charge ratio of different peak positions.

[0035] Figure 13 This is the mass spectrum of the catalyst prepared in Example 1 of this invention during the degradation of 20 mg / L tetracycline for 50 min under dark conditions, and the mass-to-charge ratio of different peak positions.

[0036] Figure 14 The catalysts prepared in Examples 1, 2 and 5 of this invention exhibit degradation performance of bisphenol A and ciprofloxacin under dark conditions.

[0037] Figure 15 This is an absorbance graph of the catalyst prepared in Example 1 of the present invention under dark conditions for a mixed solution of 20 mg / L tetracycline, 20 mg / L bisphenol A, 10 mg / L methylene blue, 10 mg / L methylene orange and 10 mg / L ciprofloxacin.

[0038] Figure 16 This is a graph showing the TOC removal rate of the catalyst prepared in Example 1 of the present invention for a mixed solution of 20 mg / L tetracycline, 20 mg / L bisphenol A, 10 mg / L methylene blue, 10 mg / L methylene orange, and 10 mg / L ciprofloxacin under dark conditions.

[0039] Figure 17 The graphs show the degradation of 20 mg / L tetracycline under dark conditions and the degradation after 10 cycles, as well as the TOC removal rate of the catalyst prepared in Example 1 of this invention. Detailed Implementation

[0040] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0041] It should be noted that the process equipment or apparatus not specifically mentioned in the following examples all use conventional equipment or apparatus in this field.

[0042] It should be noted that the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products, or apparatuses. Furthermore, unless otherwise stated, the numbering of each method step is merely a convenient tool for identifying the method steps, and not intended to limit the order of the method steps or define the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

[0043] This invention BiO 2-x The preparation method of the energy storage catalyst includes the following steps:

[0044] Step 1: Add NaBiO3·2H2O powder to NaOH solution and stir to obtain sodium bismuthate alkaline solution; wherein, the molar ratio of NaBiO3·2H2O to NaOH is (0.045~0.18):(2~4);

[0045] Step 2: Add sodium bismuthate alkaline solution dropwise to water and stir for 20 min to 120 min to obtain the reaction precursor solution; wherein, the volume ratio of the water to the NaOH solution is 1:1.

[0046] Step 3: The precursor solution is subjected to a hydrothermal reaction at 160℃~180℃ for 30min~120min. The resulting reaction product is washed and dried to obtain BiO. 2-x Energy storage catalyst.

[0047] In step 1 of this invention, the concentration of the NaOH solution is 2 mol / L to 4 mol / L. The concentration of NaBiO3·2H2O in the sodium bismuthate alkaline solution is 0.045 mmol / mL to 0.18 mmol / mL.

[0048] In step 3 of this invention, the washing process specifically involves: first, centrifuging with deionized water until the pH of the resulting supernatant is 6.5–7, and then washing three times with anhydrous ethanol. The drying process specifically involves vacuum drying at 65°C–75°C.

[0049] BiO prepared in this invention 2-x It has a cubic phase structure, space group: Fm3m(225). The BiO 2-x The catalyst is an energy storage catalyst with piezoelectric response characteristics, and its d 33 The value is 9.1767 nm·V -1 BiO under dark conditions 2-xMechanical stress disturbance causes strain, which leads to the orientation and enhancement of the internal piezoelectric polarization field. Under dark conditions, stored holes and vacancies are rapidly released to carry out catalytic reactions. At the same time, the mechanical stress disturbance strain causes BiO 2-x The energy storage catalyst generates piezoelectric charges, which are then released to continuously degrade organic pollutants.

[0050] Therefore, BiO 2-x The energy storage catalyst can catalyze the degradation of antibiotics, organic matter, dyes and mixed pollutants under dark conditions, and has good broad-spectrum cycling stability under dark conditions.

[0051] The antibiotic described in this invention is tetracycline or ciprofloxacin. The organic compound is bisphenol A. The dye is methylene blue and methylene orange. The mixed contaminant is a mixed solution of tetracycline, ciprofloxacin, methylene blue, and methylene orange B.

[0052] Comparative Example 1

[0053] Step 1: Disperse 1.8 mmol sodium bismuthate dihydrate (NaBiO3·2H2O) powder into 20 mL of 2.5 mol / L NaOH solution to obtain a sodium bismuthate mixed solution;

[0054] Step 2: Stir the mixed solution for 60 min to obtain sodium bismuthate alkaline solution. Add 20 mL of deionized water directly to the sodium bismuthate alkaline solution and stir evenly for 30 min to obtain the reaction precursor solution.

[0055] Step 3: The precursor solution was subjected to a hydrothermal reaction at 180℃ for 40 min. After the reaction was completed, the product in the reaction solution was washed, separated, and dried to obtain BiO. 2-x Materials. Washing involved multiple washes with deionized water and anhydrous ethanol, respectively. The resulting filter cake was dried at 70°C for 12 hours.

[0056] Example 1

[0057] Step 1: Disperse 1.8 mmol sodium bismuthate dihydrate (NaBiO3·2H2O) powder into 20 mL of 3 mol / L NaOH solution to obtain a sodium bismuthate mixed solution;

[0058] Step 2: Stir the mixed solution for 60 min to obtain sodium bismuthate alkaline solution. Slowly add the sodium bismuthate alkaline solution dropwise to 20 mL of deionized water and stir evenly for 30 min to obtain the reaction precursor solution.

[0059] Step 3: The precursor solution was subjected to a hydrothermal reaction at 180℃ for 40 min. After the reaction was completed, the product in the reaction solution was washed, separated, and dried to obtain BiO. 2-xMaterials. Washing involved multiple washes with deionized water and anhydrous ethanol, respectively. The resulting filter cake was dried at 70°C for 12 hours.

[0060] Example 2

[0061] Step 1: Disperse 1.8 mmol of sodium bismuthate dihydrate (NaBiO3·2H2O) powder into 20 mL of 2 mol / L NaOH solution to obtain a sodium bismuthate mixed solution;

[0062] Step 2: Stir the mixed solution for 60 min to obtain sodium bismuthate alkaline solution. Slowly add the sodium bismuthate alkaline solution dropwise to 20 mL of deionized water and stir evenly for 30 min to obtain the reaction precursor solution.

[0063] Step 3: The precursor solution was subjected to a hydrothermal reaction at 180℃ for 40 min. After the reaction was completed, the product in the reaction solution was washed, separated, and dried to obtain BiO. 2-x Materials. Washing involved multiple washes with deionized water and anhydrous ethanol, respectively. The resulting filter cake was dried at 70°C for 12 hours.

[0064] Example 3

[0065] Step 1: Disperse 1.8 mmol of sodium bismuthate dihydrate (NaBiO3·2H2O) powder into 20 mL of 2.5 mol / L NaOH solution to obtain a sodium bismuthate mixed solution;

[0066] Step 2: Stir the mixed solution for 60 min to obtain sodium bismuthate alkaline solution. Slowly add the sodium bismuthate alkaline solution dropwise to 20 mL of deionized water and stir evenly for 30 min to obtain the reaction precursor solution.

[0067] Step 3: The precursor solution was subjected to a hydrothermal reaction at 180℃ for 40 min. After the reaction was completed, the product in the reaction solution was washed, separated, and dried to obtain BiO. 2-x Materials. Washing involved multiple washes with deionized water and anhydrous ethanol, respectively. The resulting filter cake was dried at 70°C for 12 hours.

[0068] Example 4

[0069] Step 1: Disperse 1.8 mmol sodium bismuthate dihydrate (NaBiO3·2H2O) powder into 20 mL of 3.5 mol / L NaOH solution to obtain a sodium bismuthate mixed solution;

[0070] Step 2: Stir the mixed solution for 60 min to obtain sodium bismuthate alkaline solution. Slowly add the sodium bismuthate alkaline solution dropwise to 20 mL of deionized water and stir evenly for 30 min to obtain the reaction precursor solution.

[0071] Step 3: The precursor solution was subjected to a hydrothermal reaction at 180℃ for 40 min. After the reaction was completed, the product in the reaction solution was washed, separated, and dried to obtain BiO. 2-x Materials. Washing involved multiple washes with deionized water and anhydrous ethanol, respectively. The resulting filter cake was dried at 70°C for 12 hours.

[0072] Example 5

[0073] Step 1: Disperse 1.8 mmol sodium bismuthate dihydrate (NaBiO3·2H2O) powder into 20 mL of 4 mol / L NaOH solution to obtain a sodium bismuthate mixed solution;

[0074] Step 2: Stir the mixed solution for 60 min to obtain sodium bismuthate alkaline solution. Slowly add the sodium bismuthate alkaline solution dropwise to 20 mL of deionized water and stir evenly for 30 min to obtain the reaction precursor solution.

[0075] Step 3: The precursor solution was subjected to a hydrothermal reaction at 180℃ for 40 min. After the reaction was completed, the product in the reaction solution was washed, separated, and dried to obtain BiO. 2-x Materials. Washing involved multiple washes with deionized water and anhydrous ethanol, respectively. The resulting filter cake was dried at 70°C for 12 hours.

[0076] Example 6

[0077] Step 1: Disperse 0.9 mmol sodium bismuthate dihydrate (NaBiO3·2H2O) powder into 20 mL of 3 mol / L NaOH solution to obtain a sodium bismuthate mixed solution;

[0078] Step 2: Stir the mixed solution for 60 min to obtain sodium bismuthate alkaline solution. Slowly add the sodium bismuthate alkaline solution dropwise to 20 mL of deionized water and stir evenly for 30 min to obtain the reaction precursor solution.

[0079] Step 3: The precursor solution was subjected to a hydrothermal reaction at 180℃ for 40 min. After the reaction was completed, the product in the reaction solution was washed, separated, and dried to obtain BiO. 2-x Materials. Washing involved multiple washes with deionized water and anhydrous ethanol, respectively. The resulting filter cake was dried at 70°C for 12 hours.

[0080] Example 7

[0081] Step 1: Disperse 1.2 mmol sodium bismuthate dihydrate (NaBiO3·2H2O) powder into 20 mL of 3 mol / L NaOH solution to obtain a sodium bismuthate mixed solution;

[0082] Step 2: Stir the mixed solution for 60 min to obtain sodium bismuthate alkaline solution. Slowly add the sodium bismuthate alkaline solution dropwise to 20 mL of deionized water and stir evenly for 30 min to obtain the reaction precursor solution.

[0083] Step 3: The precursor solution was subjected to a hydrothermal reaction at 180℃ for 40 min. After the reaction was completed, the product in the reaction solution was washed, separated, and dried to obtain BiO. 2-x Materials. Washing involved multiple washes with deionized water and anhydrous ethanol, respectively. The resulting filter cake was dried at 70°C for 12 hours.

[0084] Example 8

[0085] Step 1: Disperse 2.4 mmol of sodium bismuthate dihydrate (NaBiO3·2H2O) powder into 20 mL of 3 mol / L NaOH solution to obtain a sodium bismuthate mixed solution;

[0086] Step 2: Stir the mixed solution for 60 min to obtain sodium bismuthate alkaline solution. Slowly add the sodium bismuthate alkaline solution dropwise to 20 mL of deionized water and stir evenly for 30 min to obtain the reaction precursor solution.

[0087] Step 3: The precursor solution was subjected to a hydrothermal reaction at 180℃ for 40 min. After the reaction was completed, the product in the reaction solution was washed, separated, and dried to obtain BiO. 2-x Materials. Washing involved multiple washes with deionized water and anhydrous ethanol, respectively. The resulting filter cake was dried at 70°C for 12 hours.

[0088] Example 9

[0089] Step 1: Disperse 3.0 mmol sodium bismuthate dihydrate (NaBiO3·2H2O) powder into 20 mL of 3 mol / L NaOH solution to obtain a sodium bismuthate mixed solution;

[0090] Step 2: Stir the mixed solution for 60 min to obtain sodium bismuthate alkaline solution. Slowly add the sodium bismuthate alkaline solution dropwise to 20 mL of deionized water and stir evenly for 30 min to obtain the reaction precursor solution.

[0091] Step 3: The precursor solution was subjected to a hydrothermal reaction at 180℃ for 40 min. After the reaction was completed, the product in the reaction solution was washed, separated, and dried to obtain BiO. 2-x Materials. Washing involved multiple washes with deionized water and anhydrous ethanol, respectively. The resulting filter cake was dried at 70°C for 12 hours.

[0092] Example 10

[0093] Step 1: Disperse 3.6 mmol of sodium bismuthate dihydrate (NaBiO3·2H2O) powder into 20 mL of 3 mol / L NaOH solution to obtain a sodium bismuthate mixed solution;

[0094] Step 2: Stir the mixed solution for 60 min to obtain sodium bismuthate alkaline solution. Slowly add the sodium bismuthate alkaline solution dropwise to 20 mL of deionized water and stir evenly for 30 min to obtain the reaction precursor solution.

[0095] Step 3: The precursor solution is subjected to a hydrothermal reaction at 180℃ for 40 min. After the reaction is completed, the product in the reaction solution is washed, separated, and dried to obtain BiO. 2-x Materials. Washing involved multiple washes with deionized water and anhydrous ethanol, respectively. The resulting filter cake was dried at 70°C for 12 hours.

[0096] Example 11

[0097] Step 1: Disperse 1.8 mmol of sodium bismuthate dihydrate (NaBiO3·2H2O) powder into 20 mL of 3 mol / L NaOH solution to obtain a sodium bismuthate mixed solution;

[0098] Step 2: Stir the mixed solution for 60 min to obtain sodium bismuthate alkaline solution. Slowly add the sodium bismuthate alkaline solution dropwise to 20 mL of deionized water and stir evenly for 30 min to obtain the reaction precursor solution.

[0099] Step 3: The precursor solution was subjected to a hydrothermal reaction at 160℃ for 40 min. After the reaction was completed, the product in the reaction solution was washed, separated, and dried to obtain BiO. 2-x Materials. Washing involved multiple washes with deionized water and anhydrous ethanol, respectively. The resulting filter cake was dried at 70°C for 12 hours.

[0100] Example 12

[0101] Step 1: Disperse 1.8 mmol of sodium bismuthate dihydrate (NaBiO3·2H2O) powder into 20 mL of 3 mol / L NaOH solution to obtain a sodium bismuthate mixed solution;

[0102] Step 2: Stir the mixed solution for 60 min to obtain sodium bismuthate alkaline solution. Slowly add the sodium bismuthate alkaline solution dropwise to 20 mL of deionized water and stir evenly for 30 min to obtain the reaction precursor solution.

[0103] Step 3: The precursor solution was subjected to a hydrothermal reaction at 170℃ for 40 min. After the reaction was completed, the product in the reaction solution was washed, separated, and dried to obtain BiO. 2-xMaterials. Washing involved multiple washes with deionized water and anhydrous ethanol, respectively. The resulting filter cake was dried at 70°C for 12 hours.

[0104] Example 13

[0105] Step 1: Disperse 1.8 mmol of sodium bismuthate dihydrate (NaBiO3·2H2O) powder into 20 mL of 3 mol / L NaOH solution to obtain a sodium bismuthate mixed solution;

[0106] Step 2: Stir the mixed solution for 60 min to obtain sodium bismuthate alkaline solution. Slowly add the sodium bismuthate alkaline solution dropwise to 20 mL of deionized water and stir evenly for 30 min to obtain the reaction precursor solution.

[0107] Step 3: The precursor solution is subjected to a hydrothermal reaction at 180℃ for 50 min. After the reaction is completed, the product in the reaction solution is washed, separated, and dried to obtain BiO. 2-x Materials. Washing involved multiple washes with deionized water and anhydrous ethanol, respectively. The resulting filter cake was dried at 70°C for 12 hours.

[0108] Example 14

[0109] Step 1: Disperse 1.8 mmol of sodium bismuthate dihydrate (NaBiO3·2H2O) powder into 20 mL of 3 mol / L NaOH solution to obtain a sodium bismuthate mixed solution;

[0110] Step 2: Stir the mixed solution for 60 min to obtain sodium bismuthate alkaline solution. Slowly add the sodium bismuthate alkaline solution dropwise to 20 mL of deionized water and stir evenly for 30 min to obtain the reaction precursor solution.

[0111] Step 3: The precursor solution is subjected to a hydrothermal reaction at 180℃ for 80 min. After the reaction is completed, the product in the reaction solution is washed, separated, and dried to obtain BiO. 2-x Materials. Washing involved multiple washes with deionized water and anhydrous ethanol, respectively. The resulting filter cake was dried at 70°C for 12 hours.

[0112] Example 15

[0113] Step 1: Disperse 1.8 mmol of sodium bismuthate dihydrate (NaBiO3·2H2O) powder into 20 mL of 3 mol / L NaOH solution to obtain a sodium bismuthate mixed solution;

[0114] Step 2: Stir the mixed solution for 60 min to obtain sodium bismuthate alkaline solution. Slowly add the sodium bismuthate alkaline solution dropwise to 20 mL of deionized water and stir evenly for 30 min to obtain the reaction precursor solution.

[0115] Step 3: The precursor solution is subjected to a hydrothermal reaction at 180℃ for 100 min. After the reaction is completed, the product in the reaction solution is washed, separated, and dried to obtain BiO. 2-x Materials. Washing involved multiple washes with deionized water and anhydrous ethanol, respectively. The resulting filter cake was dried at 70°C for 12 hours.

[0116] Example 16

[0117] Step 1: Disperse 1.8 mmol of sodium bismuthate dihydrate (NaBiO3·2H2O) powder into 20 mL of 3 mol / L NaOH solution to obtain a sodium bismuthate mixed solution;

[0118] Step 2: Stir the mixed solution for 60 min to obtain sodium bismuthate alkaline solution. Slowly add the sodium bismuthate alkaline solution dropwise to 20 mL of deionized water and stir evenly for 30 min to obtain the reaction precursor solution.

[0119] Step 3: The precursor solution was subjected to a hydrothermal reaction at 180℃ for 120 min. After the reaction was completed, the product in the reaction solution was washed, separated, and dried to obtain BiO. 2-x Materials. Washing involved multiple washes with deionized water and anhydrous ethanol, respectively. The resulting filter cake was dried at 70°C for 12 hours.

[0120] The following provides a detailed explanation of the above conclusions and mechanisms.

[0121] Figure 1 These are XRD patterns of the catalysts prepared in Examples 1, 2, and 5 of this invention. BiO 2-x Diffraction peaks appear at 2θ values ​​of 28.2°, 32.7°, 46.9°, 55.6°, and 58.3°, corresponding to the (111), (200), (220), (311), and (222) crystal planes, respectively, corresponding to the cubic phase BiO. 2-x This is consistent with the standard card (space group: Fm3m(225)) (JCPDS: 47-1057). This indicates that cubic BiO2 was prepared hydrothermally. 2-x .

[0122] Figure 2 These are Raman spectroscopy plots of the catalysts prepared in Examples 1, 2, and 5 of this invention. BiO 2-x Catalyst at 119 cm -1 The characteristic peak at 138 cm⁻¹ corresponds to the vibration of the Bi atom. -1 310 cm -1 439 cm -1 The characteristic peak at 182 cm⁻¹ corresponds to the stretching vibration of the Bi-O bond. -1 207 cm-1 The characteristic peak at that location is attributed to the vibration of the O atom. This further demonstrates that the present invention successfully prepared cubic BiO₂. 2-x .

[0123] Figure 3 This is a SEM image of the catalyst prepared in Example 1 of this invention. The prepared BiO₂ 2-x The morphology shows tetragonal nanosheets with side lengths of 0.2 μm to 0.5 μm and nanorods with lengths of approximately 0.3 μm and diameters of approximately 50 to 80 nm.

[0124] Figure 4 HRTEM images of Example 1 of this invention. The images show lattice spacings of 0.317 nm, 0.271 nm, 0.1937 nm, and 0.1658 nm, corresponding to BiO₂, respectively. 2-x The (111), (200), (220), and (311) crystal planes indicate that cubic BiO was prepared hydrothermally. 2-x .

[0125] Figure 5 This is the absorbance curve of the catalyst prepared in Example 1 of this invention for 20 mg / L methylene blue under dark conditions. The BO value can be calculated from the methylene blue absorbance curve. 2-x The stored electron concentration is 9.89 μmol·g -1 Therefore, the BiO prepared by this invention 2-x It is an energy storage catalyst.

[0126] Figure 6 The catalyst prepared in Example 1 of this invention under dark conditions h + The electron paramagnetic resonance spectrum was obtained through calculation. 2-x The stored hole concentration was 233.18 μmol·g. -1 This further proves that the BiO prepared by this invention 2-x It is an energy storage catalyst.

[0127] Figure 7 This is a phase change diagram of the catalyst prepared in Example 1 of this invention. BiO 2-x After applying a deflection voltage of 10 V, the phase angle flipped by about 180°, proving that the dipole is easily transformed by an external electric field.

[0128] Figure 8 This is an amplitude variation diagram of Example 1 of the present invention. Under the action of an electric field, BiO 2-x The amplitude variation graphs all showed typical "butterfly-shaped curves," indicating strain-electric field hysteresis, which also proves that BiO 2-x BiO exhibits a significant piezoelectric response at the nanoscale, and its piezoelectric "butterfly curve" was used to calculate the piezoelectric response. 2-xd 33 The value is 9.1767 nm·V -1 This demonstrates good piezoelectric properties. The large piezoelectric polarization characteristics can induce the energy storage catalyst to store charge and generate piezoelectric charge under mechanical stress, thereby improving its dark catalytic activity.

[0129] Figure 9 This is the current graph of Example 1 of the present invention under dark conditions. Under dark conditions without mechanical stress disturbance, the current curve changes essentially as a straight line over time. With the application of mechanical stress disturbance, a significant increase in current amplitude over time can be observed. The current increases with the application of mechanical stress disturbance, and as time continues, the current exhibits sawtooth-like fluctuations. When the mechanical stress disturbance is stopped, the current decreases rapidly. The application of mechanical stress disturbance shows periodic fluctuations, which also proves that BiO 2-x Under dark conditions, the application of mechanical stress disturbance induces a positive piezoelectric effect, generating piezoelectric charges, indicating that BiO 2-x It exhibits obvious piezoelectric response characteristics under stress.

[0130] Figure 10 This invention describes the degradation performance of the catalysts prepared in Examples 1, 2, 5, and Comparative Example 1 on 20 mg / L tetracycline. Under dark conditions, the catalysts in Examples 1, 2, and 5 achieved degradation rates of 80.24%, 77.11%, and 79.24% of 20 mg / L TC, respectively, after 60 min; while the catalyst in Comparative Example 1 only achieved a degradation rate of 66.4% of 20 mg / L TC under dark conditions. This indicates that the sodium bismuthate alkaline solution was added dropwise to water, and the added BiO3... - Able to interact with H + Rapid binding results in the uniform formation of HBiO3·BiO3 of uniform size in the solution. - Colloidal particles, which in turn form oxygen vacancies and Bi 3+ / Bi 5+ However, if water is added directly to a sodium bismuthate alkaline solution, a large amount of water will dissociate to form H+. + With BiO3 in solution - Rapidly combining to form a large number of small HBiO3 crystal nuclei, these nuclei then aggregate and crystallize in a hydrothermal high-temperature environment to form BiO. 2-x Crystal, Bi in HBiO3 small crystal nuclei 5+ Easy to fully restore Bi 3+ However, the oxygen concentration in the HBiO3 crystal nuclei in the solution is higher than that in the closed hydrothermal environment. Oxygen escapes from the HBiO3 crystal nuclei in the solution, forming O2, causing oxygen deficiency inside the crystal (2HBiO3 → 2BiO). 2-x The reaction (+O2↑+ H2O) causes the catalyst crystals prepared by directly adding water to a sodium bismuthate alkaline solution to store only electrons, resulting in a significant reduction in their degradation rate under dark conditions.

[0131] Figure 11 The figures show the removal rates of 40 mg / L tetracycline TOC by the catalysts prepared in Examples 1, 2, and 5 of this invention. The removal rates of organic carbon from the degradation products of 20 mg / L TC in Examples 1, 2, and 5 are 28%, 25%, and 23%, respectively, indicating that the catalysts of this invention have high catalytic activity under dark conditions.

[0132] Figure 12 and Figure 13 The images show the mass spectra of the catalyst prepared in Example 1 of this invention degrading 20 mg / L tetracycline under dark conditions for 10 min and 50 min, respectively. LC-MS analysis revealed that tetracycline transformed from a high mass-to-charge ratio (m / z=445) molecule into a smaller molecule, further demonstrating the degradation of BiO₂. 2-x The catalyst can degrade tetracycline into CO2, H2O, and small molecule organic compounds, BiO, under dark conditions. 2-x The catalyst is an energy storage piezoelectric catalytic material.

[0133] Figure 14 This invention describes the degradation performance of the catalysts prepared in Examples 1, 2, and 5 on bisphenol A and ciprofloxacin. In the dark, the degradation rates of bisphenol A in Examples 1, 2, and 5 reached 93.89%, 94.97%, and 91.73% respectively after 60 min; the degradation rates of ciprofloxacin reached 24.1%, 29%, and 25.92% respectively.

[0134] Figure 15 and Figure 16 The images show the absorbance and TOC removal rates of the catalyst prepared in Example 1 of this invention under dark conditions for a mixed solution of 20 mg / L tetracycline, 20 mg / L bisphenol A, 10 mg / L methylene blue, 10 mg / L methylene orange, and 10 mg / L ciprofloxacin. As the degradation time increases, the absorption band gradually weakens, and the TOC removal rate is 28.15%, indicating that BiO2... 2-x The catalyst exhibits good degradation performance on mixed pollutant solutions, and the prepared BiO2... 2-x The energy storage catalyst is universal and can degrade a variety of antibiotics, organics and dyes under dark conditions.

[0135] Figure 17 This diagram shows the degradation of 20 mg / L tetracycline by the catalyst prepared in Example 1 of this invention under dark conditions, including cyclic degradation and TOC removal rates after 10 cycles under dark conditions. The catalyst's catalytic activity for TC degradation under dark conditions gradually decreases with increasing reaction time. After 10 cycles, the degradation efficiency of TC gradually decreases. 2-xThe energy storage catalyst exhibited a 22% degradation rate of TC; during the 1st, 4th, 7th, and 10th reaction cycles, BiO... 2-x The TOC removal rates of the energy storage catalyst for TC were 26.92%, 6.02%, 9.82%, and 6.71%, respectively, indicating that BiO2... 2-x The energy storage catalyst exhibits good cycle stability and strong dark catalytic ability under dark conditions.

[0136] This invention prepares non-stoichiometric BiO3 via a one-step hydrothermal method. 2-x Energy storage catalyst, BiO under dark conditions 2-x Mechanical stress disturbance causes strain, which enhances the internal piezoelectric polarization field and rapidly releases stored electrons and holes for catalytic reaction under dark conditions. Simultaneously, the mechanical stress disturbance strain causes BiO 2-x The energy storage catalyst generates piezoelectric charges, which are then released to continuously degrade antibiotics tetracycline and ciprofloxacin, organic compounds bisphenol A, and dyes methylene blue and methylene orange.

[0137] The above description is only one embodiment of the present invention, and not all or the only embodiment. Any equivalent modifications made by those skilled in the art to the technical solution of the present invention by reading the present invention specification are covered by the claims of the present invention.

Claims

1. A BiO 2-x A method for producing a high-energy catalyst, characterized by, The method comprises the following steps: Step 1, NaBiO3·2H2O powder is added into NaOH solution, and stirring is conducted to obtain a sodium bismuthate alkali solution; wherein the molar ratio of NaBiO3·2H2O to NaOH is (0.045-0.18):(2-4); Step 2, the sodium bismuthate alkali solution is added dropwise into water, and stirring is conducted to obtain a reaction precursor solution; Step 3, the reaction precursor solution is subjected to hydrothermal reaction at 160-180 °C for 30-120 min, and the obtained reaction product is washed and dried to obtain BiO 2-x Energy storage catalyst.

2. A BiO 2-x The preparation method of the energy storage catalyst is characterized by comprising the following steps: In step 1, the concentration of the NaOH solution is 2 mol / L-4 mol / L.

3. A BiO 2-x The preparation method of the energy storage catalyst is characterized by comprising the following steps: In step 2, the stirring time is 20 min-120 min.

4. A BiO 2-x The preparation method of the energy storage catalyst is characterized by comprising the following steps: In step 3, the washing is specifically: firstly, centrifugal cleaning is conducted with deionized water until the pH of the obtained supernatant is 6.5-7, and then the washing is conducted multiple times with anhydrous ethanol.

5. A BiO 2-x The preparation method of the energy storage catalyst is characterized by comprising the following steps: In step 3, the drying is specifically: vacuum drying is conducted at 65-75 DEG C.

6. A BiOx obtained by the production method according to any one of claims 1 to 5. 2-x An energy storage catalyst characterized by comprising: The BiO 2-x The energy storage catalyst is in a cubic phase with a space group of Fm-3m, BiO 2-x The energy storage catalyst stores electrons and holes.

7. The BiO of claim 6 2-x Use of a stored energy catalyst to catalyze the degradation of organic pollutants in the dark.

8. Use according to claim 7, characterized in that, The organic pollutants are antibiotics or dyes.

9. The BiO of claim 6 2-x Use of energy storage catalysts in catalytic degradation of organic pollutants.

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