Method for generating based on o-zn in2s4 photocatalytic bisphenol a degradation synergistic h2o2

Abstract

This invention discloses a method for the photocatalytic degradation of bisphenol A and the synergistic generation of H2O2 based on O-ZnIn2S4, comprising: adding the O-ZnIn2S4 photocatalytic material to wastewater containing bisphenol A, and performing photocatalytic degradation of bisphenol A and in-situ generation of H2O2 under visible light irradiation. Under light conditions, the O-ZnIn2S4 photocatalytic material of this invention exhibits excellent activity in the organic matter degradation reaction, while its H2O2 generation rate is high. The system of this invention achieves synergistic coupling of organic pollutant removal and in-situ hydrogen peroxide generation, providing a new photocatalytic strategy for green and efficient hydrogen peroxide synthesis and environmental remediation.

Description

Technical Field

[0001] This invention relates to the field of functional materials technology, and in particular to a method based on the photocatalytic degradation of bisphenol A and the synergistic generation of H2O2 using O-ZnIn2S4. Background Technology

[0002] Bisphenol A (BPA) is a synthetic chemical widely used in the synthesis of epoxy resins, polymer materials, and polycarbonate plastics. These plastics are commonly used in food storage and baby bottles, and BPA can be incorporated into soil or water through leaching. The concentration of BPA in aquatic environments can reach thousands of ng / L. -1 BPA, as a potent endocrine disruptor, has anti-androgenic effects and estrogen-like effects, leading to problems such as reproductive developmental abnormalities, endocrine disruption, and metabolic diseases.

[0003] Hydrogen peroxide (H2O2), as a green and efficient oxidant, is widely used in environmental remediation, fine chemicals, and energy conversion, and market demand continues to grow. However, the mainstream industrial process for preparing H2O2 is the anthraquinone process, which typically suffers from problems such as long process flow, large equipment investment, high energy consumption, and the use of organic solvents and potential pollution emissions. In addition, as an active chemical, the storage and transportation of H2O2 also pose certain safety risks, making it difficult to meet the requirements of green, simplified processes and safety for distributed, on-site preparation and emergency remediation applications.

[0004] Photocatalysis, a solar-powered technology for the synthesis of environmental and chemical products, has been applied in recent years to the degradation of organic pollutants and the generation of H2O2. However, existing photocatalytic systems often focus on a single objective, such as degrading pollutants or generating only H2O2, failing to achieve synergy between pollution control and resource utilization. Furthermore, traditional photocatalytic materials generally suffer from severe recombination of photogenerated carriers, low interfacial charge transfer efficiency, and insufficient redox capacity, resulting in limited pollutant removal efficiency or low H2O2 generation rate and selectivity, making it difficult to simultaneously meet the dual functional requirements of efficient decontamination and high H2O2 production.

[0005] CN119869618A discloses a bifunctional catalyst comprising a support and single-atom Ag and nano-Ag clusters dispersed on the support, which has the dual functions of synthesizing hydrogen peroxide and efficiently degrading tetracycline in wastewater.

[0006] Zhao J et al. (Zhao J, Ali A, Kadhum A et al. Boosting photocatalytic H2O2 production and non-biodegradable ofloxacin removal via a novel Ti3C2MXenenanosheet-supported BiVO4 / InVO4Z-scheme heterojunction: Optimization and mechanism insights. Journal of Water Process Engineering (2025) 74) disclosed a Ti3C2Mxene-supported BiVO4 / InVO4 Z-scheme heterojunction photocatalyst that simultaneously achieves efficient degradation of ofloxacin (OFX) and hydrogen peroxide generation under visible light.

[0007] However, existing methods for preparing bifunctional catalysts are complex and costly. Summary of the Invention

[0008] This invention provides a method for the photocatalytic degradation of bisphenol A and the synergistic generation of H2O2 based on O-ZnIn2S4. This method can achieve the synergistic coupling of efficient removal of organic pollutants and green preparation of H2O2 in the same reaction system, and has the dual functions of environmental remediation and high value-added chemical synthesis.

[0009] The technical solution of the present invention is as follows: A method based on O-ZnIn2S4 photocatalytic degradation of bisphenol A and synergistic H2O2 generation includes: adding the O-ZnIn2S4 photocatalytic material to wastewater containing bisphenol A, and performing photocatalytic degradation of bisphenol A and in-situ generation of H2O2 under visible light irradiation.

[0010] Under illumination, the O-ZnIn2S4 photocatalytic material of this invention exhibits excellent activity in the degradation of bisphenol A (BPA); simultaneously, its H2O2 generation rate reaches a high level. This system achieves synergistic coupling between organic pollutant removal and in-situ hydrogen peroxide generation, providing a novel photocatalytic strategy for green and efficient hydrogen peroxide synthesis and environmental remediation.

[0011] Preferably, the preparation method of the O-ZnIn2S4 photocatalytic material includes the following steps: (1) Dissolve the zinc source compound, indium source compound, sulfur source compound and polyvinylpyrrolidone (PVP) in a solvent, and react the resulting mixed solution in a high-pressure reactor at 150-200℃ for 10-40h; (2) After the reaction is complete, the precipitate is separated from the reaction solution, washed and dried to obtain O-ZnIn2S4 photocatalytic material.

[0012] This invention achieves controllable oxygen doping in the ZnIn2S4 lattice by adding polyvinylpyrrolidone (PVP) during the solvothermal process, inducing the formation of new electronic energy levels and thus effectively controlling the band structure of the material. Oxygen-doped ZnIn2S4 significantly promotes the separation and migration of photogenerated carriers, suppresses electron-hole recombination, and thereby enhances photocatalytic performance.

[0013] Preferably, the solvent is an ethanol-water mixture, with a volume ratio of ethanol to water of 0.5-2:1.

[0014] Preferably, the ratio of zinc source compound, indium source compound, sulfur source compound and polyvinylpyrrolidone is 1 mmol: (1.5-2.5) mmol: (6-10) mmol: (0.1-2) g.

[0015] More preferably, the ratio of zinc source compound, indium source compound, sulfur source compound and polyvinylpyrrolidone is 1 mmol: (1.5-2.5) mmol: (7-9) mmol: (0.1-1) g.

[0016] Preferably, in the mixed solution of step (1), the concentration of the zinc source compound is 0.01-0.1 mol / L.

[0017] More preferably, the zinc source compound is zinc chloride, the indium source compound is indium chloride, and the sulfur source compound is thioacetamide (TAA).

[0018] Preferably, in step (1), the reaction temperature is 160-180℃ and the reaction time is 12-36 h.

[0019] Preferably, in step (2), after the reaction is completed, the reaction solution is centrifuged at 9500-11000 rpm for 6-10 min and the precipitate is collected; the precipitate is washed multiple times with deionized water and ethanol respectively; the washed precipitate is vacuum dried at 50-80℃ for 8-24 h to obtain O-ZnIn2S4 photocatalytic material.

[0020] Preferably, the concentration of bisphenol A in the wastewater is 1-100 mg / L.

[0021] This invention provides a method and system for coupling photocatalytic degradation of organic pollutants with in-situ generation of hydrogen peroxide (H2O2). This system constructs an efficient photogenerated carrier separation and interfacial directional transport structure to drive simultaneous interfacial oxidation and reduction reactions, achieving synergistic coupling between organic pollutant degradation and in-situ H2O2 generation. Under illumination, photogenerated electrons generated by the catalyst preferentially participate in O2 activation, and their single electrons are first reduced to ·O2. - Among them, O2 - One part participates in the oxidative degradation of organic pollutants as the dominant reactive oxygen species, while the other part, with the participation of protons, achieves in-situ generation and continuous accumulation of H2O2 along a two-step single-electron oxygen reduction pathway.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) This invention provides a method for preparing a bifunctional catalyst with synergistic H2O2 degradation of pollutants. The preparation process is simple, the material yield is high, and no additional energy is required, which reduces the cost and makes it easy to process into production.

[0023] (2) Unlike traditional synergistic systems that rely on external oxidants or metal-based Fenton activation, O-ZnIn2S4 achieves simultaneous enhancement of pollutant removal and in-situ H2O2 generation by regulating the separation of photogenerated carriers and the two-electron reduction pathway of O2; (3) The catalyst reduces the potential risks of chemical addition and metal leaching, and has better green safety and engineering adaptability. Attached Figure Description

[0024] Figure 1 The emission scanning electron microscope (SEM) image of O-ZnIn2S4 prepared in Example 1; Figure 2 X-ray powder diffraction patterns of O-ZnIn2S4 prepared in Example 1 and ZnIn2S4 prepared in Comparative Example 1; Figure 3 X-ray photoelectron spectra of O-ZnIn2S4 prepared in Example 1 and ZnIn2S4 prepared in Comparative Example 1; Figure 4 The graph shows the performance of O-ZnIn2S4 photocatalytic degradation of bisphenol A and synergistic H2O2 generation prepared in Example 1. Figure 5 The graphs show the performance of O-ZnIn2S4 photocatalytic degradation of bisphenol A prepared in Examples 1-5. Figure 6 The graphs show the performance of O-ZnIn2S4 photocatalytic degradation of bisphenol A prepared in Examples 1 and 6-8. Detailed Implementation

[0025] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be noted that the embodiments described below are intended to facilitate the understanding of the present invention and do not limit it in any way.

[0026] Example 1 0.4 mmol zinc chloride, 0.8 mmol indium chloride tetrahydrate, 3.2 mmol thioacetamide, and 0.2 g polyvinylpyrrolidone (PVP) (average molecular weight 10000) were dissolved sequentially in 30 mL of ethanol-water (1:1 v / v) mixture and stirred at room temperature for 10 min. The homogeneous solution was transferred to a 45 mL autoclave and reacted in a 180 °C drying oven for 18 h. After the autoclave cooled to room temperature, the reaction solution was centrifuged at 10000 rpm for 10 min to obtain a yellow precipitate. The product was washed three times with deionized water and ethanol, respectively, and finally dried in a vacuum drying oven at 60 °C for 12 h to obtain the product O-ZnIn2S4.

[0027] Comparative Example 1 0.4 mmol zinc chloride, 0.8 mmol indium chloride tetrahydrate, and 3.2 mmol thioacetamide were dissolved sequentially in 30 mL of a ethanol-water (1:1 v / v) mixture and stirred at room temperature for 10 min. The homogeneous solution was transferred to a 45 mL autoclave and reacted in a 180 °C drying oven for 18 h. After the autoclave cooled to room temperature, the reaction solution was centrifuged at 10,000 rpm for 10 min to obtain a yellow precipitate. The product was washed three times with deionized water and ethanol, respectively, and finally dried in a vacuum drying oven at 60 °C for 12 h to obtain ZnIn2S4.

[0028] The preparation method of ZnIn2S4 is similar to that of O-ZnIn2S4, except that polyvinylpyrrolidone is not added during the synthesis process.

[0029] The morphology of O-ZnIn2S4 was characterized using SEM, such as... Figure 1 As shown, O-ZnIn2S4 exhibits the morphology of ultrathin nanosheets.

[0030] The photocatalyst O-ZnIn2S4 prepared in Example 1 was characterized and analyzed by XRD, and the results are as follows: Figure 2As shown, the diffraction peaks of O-ZnIn2S4 and hexagonal ZnIn2S4 (PDF#72-0773) match well. The diffraction peaks of O-ZnIn2S4 at 21.59°, 27.69°, 39.77°, 47.18°, and 55.58° correspond to the (006), (102), (106), (110), (116), and (202) crystal planes, respectively. Moreover, no impurities such as ZnO and In2O3 were observed, indicating that the photocatalyst O-ZnIn2S4 prepared in Example 1 has high purity.

[0031] To further analyze the chemical state of oxygen, a fitting analysis was performed on the O 1s high-resolution spectrum, such as... Figure 3 As shown, ZnIn2S4 without PVP exhibits two characteristic peaks at 531.10 eV and 532.29 eV, corresponding to adsorbed hydroxyl groups (·OH) and adsorbed water molecules, respectively, indicating the presence of a small amount of adsorbed oxygen species on the original ZnIn2S4 surface. With the addition of PVP, the O 1s high-resolution spectrum of the O-ZnIn2S4 sample splits into three peaks at approximately 530.20 eV, 531.27 eV, and 532.50 eV, corresponding to lattice oxygen (·O2-), surface hydroxyl groups, and adsorbed water, respectively. The peak at 530.20 eV can be attributed to oxygen elements entering the ZnIn2S4 lattice, indicating successful oxygen doping into the lattice structure and successful synthesis of O-ZnIn2S4.

[0032] Application Example 1 20 mg each of the O-ZnIn2S4 photocatalyst prepared in Example 1 and the ZnIn2S4 photocatalyst prepared in Comparative Example 1 were ultrasonically dispersed in 50 mL of a 20 mg / L bisphenol A (BPA) solution and allowed to adsorb in the dark for 30 min to allow the photocatalyst and bisphenol A molecules to reach adsorption-desorption equilibrium. A 300W xenon lamp (with a filter cutoff wavelength) was used. Irradiation was performed using ≥400 as a light source. During the degradation process, 1 mL of the reaction solution was taken out at time intervals, and catalyst particles were filtered out using a PTFE filter membrane. The H2O2 generation and bisphenol A residual concentration were analyzed using a UV-Vis spectrophotometer and ultra-high performance liquid chromatography, respectively.

[0033] The results are as follows Figure 4As shown, O-ZnIn2S4 exhibits superior performance compared to ZnIn2S4 in both BPA removal and H2O2 generation, indicating a more prominent synergistic effect of "pollutant degradation-hydrogen peroxide generation." Regarding BPA degradation, O-ZnIn2S4 achieves >98% removal within 20 min, while ZnIn2S4 removes only 79.5% in the same timeframe. The degradation rate of O-ZnIn2S4 is 2.47 times that of ZnIn2S4, demonstrating that oxygen doping significantly accelerates the photocatalytic degradation kinetics of BPA. Simultaneously, the cumulative H2O2 concentration of O-ZnIn2S4 reaches 353.06% within 20 min. M is higher than ZnIn2S4's 311.76. M was increased by approximately 13.2%. These results indicate that O-ZnIn2S4 not only drives the oxidative removal of BPA more efficiently, but also facilitates the participation of electrons in the dissolved oxygen reduction process and promotes the generation of H2O2, thereby achieving a more efficient bifunctional coupling system.

[0034] Examples 2-5 The amount of polyvinylpyrrolidone added in Example 1 was adjusted from 0.20g to 0.05g, 0.10g, 0.40g, and 0.80g, respectively, while other conditions remained the same as in Example 1.

[0035] In the preparation of O-ZnIn2S4, the amount of PVP added and the synthesis time were adjusted (Examples 1-5). Following the method in Example 1, the degradation effect of O-ZnIn2S4 with different amounts of PVP (0.05g, 0.10g, 0.20g, 0.40g, 0.80g) on ​​BPA was tested, and the results are as follows: Figure 5 As shown, all materials were able to degrade more than 99% of BPA within 40 minutes. The fastest degradation rate was observed when PVP was added at 0.20 g; however, excessively low (0.05 g) or high (0.40-0.80 g) PVP additions led to a decrease in photocatalytic activity. PVP plays two main roles in the reaction system: structural regulation and oxygen doping induction. As a soft template and surface complexing agent, PVP effectively regulates crystal growth rate and optimizes the lamellar structure and exposed crystal faces of the material. Simultaneously, appropriate amounts of PVP under solvothermal conditions can promote the introduction of oxygen, modulate the electronic structure of the material, and thus enhance photocatalytic activity. However, excessive PVP has significant negative effects. Too much organic residue may cover the active sites on the material surface, hindering the migration of photogenerated carriers, and may also lead to oversaturation of structural defects, forming recombination centers for photogenerated carriers. In summary, 0.20 g is the optimal addition amount of PVP, achieving the best balance between structural and defect regulation.

[0036] Examples 6-8 The reaction time in Example 1 was adjusted from 18h to 12h, 24h, and 36h respectively, while other conditions remained the same as in Example 1.

[0037] The solvothermal reaction time mainly determines the crystal growth integrity, oxygen doping degree, and defect density and distribution. Therefore, the catalytic activity of materials with different reaction times was investigated (Examples 1, Examples 6-8). The degradation effect of O-ZnIn2S4 on BPA at different reaction times (12h, 18h, 24h, 36h) was tested according to the method in Example 1. The results are as follows: Figure 6 As shown in the figure. Experimental results show that the material with a reaction time of 24 h exhibits the fastest degradation rate, the sample with a reaction time of 12 h has slightly lower photocatalytic activity, while the materials with reaction times of 18 h and 36 h have intermediate photocatalytic degradation rates of BPA. At a reaction time of 12 h, the crystals are not fully mature, resulting in insufficient active sites and low catalytic activity; when the reaction time is extended to 18 h, the crystal structure tends to be more complete, and the defect distribution is more uniform; when the reaction time is too long (36 h), the grains continue to grow, leading to a reduction in the number of active sites on the material surface, which in turn prevents further improvement in photocatalytic performance. Therefore, 18 h of reaction time was chosen as the subsequent synthesis time.

[0038] The embodiments described above provide a detailed explanation of the technical solutions and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, additions, and equivalent substitutions made within the scope of the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for the photocatalytic degradation of bisphenol A and synergistic H2O2 generation based on O-ZnIn2S4, characterized in that, include: The O-ZnIn2S4 photocatalytic material was added to wastewater containing bisphenol A, and photocatalytic degradation of bisphenol A and in-situ generation of H2O2 were carried out under visible light irradiation.

2. The method according to claim 1, characterized in that, The preparation method of the O-ZnIn2S4 photocatalytic material includes the following steps: (1) Dissolve the zinc source compound, indium source compound, sulfur source compound and polyvinylpyrrolidone in a solvent, and react the resulting mixed solution in a high-pressure reactor at 150-200℃ for 10-40h; (2) After the reaction is complete, the precipitate is separated from the reaction solution, washed and dried to obtain O-ZnIn2S4 photocatalytic material.

3. The method according to claim 2, characterized in that, The solvent is an ethanol-water mixture, with a volume ratio of ethanol to water of 0.5-2:

1.

4. The method according to claim 2, characterized in that, The ratio of zinc source compound, indium source compound, sulfur source compound and polyvinylpyrrolidone is 1 mmol: (1.5-2.5) mmol: (6-10) mmol: (0.1-2) g.

5. The method according to claim 2 or 4, characterized in that, In the mixed solution of step (1), the concentration of the zinc source compound is 0.01-0.1 mol / L.

6. The method according to claim 2 or 4, characterized in that, The zinc source compound is zinc chloride, the indium source compound is indium chloride, and the sulfur source compound is thioacetamide.

7. The method according to claim 2, characterized in that, In step (1), the reaction temperature is 160-180℃ and the reaction time is 12-36 h.

8. The method according to claim 2, characterized in that, In step (2), after the reaction is completed, the reaction solution is centrifuged at 9500-11000 rpm for 6-10 min and the precipitate is collected. The precipitate is washed multiple times with deionized water and ethanol respectively. The washed precipitate is dried under vacuum at 50-80℃ for 8-24 h to obtain O-ZnIn2S4 photocatalytic material.

9. The method according to claim 2, characterized in that, The concentration of bisphenol A in the wastewater is 1-100 mg / L.

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