An anodic functional material for controlled generation of singlet oxygen assisted by electric field and its preparation method

Abstract

This invention discloses an anodic functional material and its preparation method, belonging to the fields of advanced oxidation technology and water treatment. The anodic functional material uses nickel foam as a substrate, on which vertically aligned reduced graphene oxide (rGO) and an ordered array of hexagonal Co3S4 nanosheets are sequentially loaded, forming an rGO@Co3S4-NF composite structure. Under the assistance of an electric field, this anodic functional material can efficiently activate negatively charged permonosulfate (PMS), significantly promoting the oxidation of free radicals. 1 The conversion of O2 can be used for the efficient degradation and removal of pollutants such as tetracycline. Moreover, it can maintain stable and efficient degradation performance in a wide pH range (3-11) and high salinity environment, providing a new strategy for efficient water treatment.

Description

Technical Field

[0001] This invention belongs to the field of advanced oxidation technology and water treatment, specifically relating to an anodic functional material with a specific ordered structure and its preparation method, and the controllable generation of singlet oxygen from persulfate (PMS) under an electric field assistance. 1 O2), which is then used in the degradation of organic pollutants. Background Technology

[0002] Advanced oxidation technologies have attracted much attention in water treatment due to their efficient ability to degrade organic pollutants. Traditional free radicals (such as ·OH, SO42-) - ·) It suffers from problems such as short lifetime and poor selectivity. Singlet oxygen ( 1 O2, as a non-radical reactive species, has advantages such as a long half-life, good selectivity, and strong anti-interference ability, but its controllable generation still faces challenges. Currently 1 The generation of O2 largely depends on the regulation of catalyst structure, and its preparation is complex and costly, which limits its practical application.

[0003] Peroxymonosulfate (PMS) is a commonly used oxidant, and its activation products include free radicals and non-free radical species. How to efficiently and controllably convert PMS to... 1 O2 has become a current research hotspot. Electric field-assisted techniques, by modulating the mass transfer behavior of charged species, can enhance local reaction concentrations and hold promise for achieving… 1 The efficient generation of O2 is a key technology. However, the current lack of efficient and stable anode materials to match this technology hinders its development.

[0004] Chinese patent CN 120097468A discloses a method for electrochemically activated persulfate to degrade benzene compounds in wastewater while simultaneously inhibiting bromate formation. This method employs an electrochemically activated persulfate system, controlling current density and cathodic reduction to suppress bromate formation while degrading benzene compounds. This system primarily relies on the free radical pathway (SO4). - While the text mentions oxidative degradation of · and HO·, and mentions cathodic reduction to suppress byproducts, it does not address singlet oxygen (…). 1 The generation and utilization of O2 lacks regulation of non-radical pathways, and its anode material is ruthenium titanium, which has a high cost.

[0005] Chinese patent CN 119608167A discloses a composition for degrading triazole fungicides and its application, which uses nickel foam as a carrier to support cobalt-nickel layered bimetallic oxide as a catalyst to activate persulfate and synergistically generate free radicals (SO4). - ·、O2 - ·) and non-free radicals ( 1O2) degrades triazole bactericides. Although this catalyst can generate singlet oxygen, its generation depends on the oxygen vacancies and metal sites within the material itself. The lack of external electric field regulation of reaction mass transfer and active species distribution leads to insufficient singlet oxygen generation efficiency and controllability. Furthermore, since the catalyst is in powder or supported form, it does not work in conjunction with the electric field to construct a directional enrichment and activation mechanism, and its anti-interference ability and stability in complex water bodies may be weak.

[0006] Chinese patent CN 118289894A discloses a CoxSy / carbon cloth composite anode material and measures its electro-activated persulfate degradation performance of sulfamethoxazole. However, its activation efficiency is limited, with a degradation rate of approximately 90.86% after 10 minutes, and it mainly relies on the free radical pathway, showing limited effectiveness against non-free radicals. 1 O2 generation lacks effective regulation.

[0007] Chinese patent CN 108706573A discloses a graphene-based hollow cobalt sulfide nanocrystal that can be used for the degradation of organic matter. It introduces graphene to enhance conductivity and dispersibility, but its structure is a hollow nanocrystal. It does not involve research on enhancing mass transfer and reaction by using ordered arrays under an electric field, and its degradation time is relatively long, with 97% degradation in 8 minutes.

[0008] In summary, existing technologies still have the following common problems: weak mass transfer control capability and low concentration of anode surface reactant (PMS), which limits the reaction rate; 1 O2 generation efficiency is low and uncontrollable, mainly relying on intrinsic material properties and lacking active regulation by external physical fields; the material structure is suboptimal, active sites are not fully exposed, and electron transport efficiency needs improvement. Therefore, developing an anode material that combines electric field mass transfer regulation with optimal geometry and electronic structure is crucial for achieving [the desired result]. 1 The key to efficient and controllable O2 generation. Summary of the Invention

[0009] The purpose of this invention is to provide an anodic functional material for the controllable generation of singlet oxygen assisted by an electric field and its preparation method, so as to overcome the problems of low singlet oxygen generation efficiency, dependence on complex catalyst structure, weak mass transfer control ability, and insufficient environmental adaptability and material stability in the prior art.

[0010] To achieve the above objectives, the present invention adopts the following technical solution: One objective of this invention is to protect an anodic functional material for the controlled generation of singlet oxygen assisted by an electric field. This material uses nickel foam as a substrate, on which vertically aligned reduced graphene oxide (rGO) is first loaded. Then, ordered Co3S4 nanosheets are further loaded onto the surface of the reduced graphene oxide, forming an rGO@Co3S4-NF composite structure. The Co3S4 nanosheets grow epitaxially along the direction perpendicular to the reduced graphene oxide, forming an ordered hexagonal nanosheet array, which enhances the exposure of active sites and electron transport capabilities.

[0011] Scanning electron microscopy showed that Co3S4 nanosheets in the anodic functional material rGO@Co3S4-NF grew in an orderly manner along the vertical direction of rGO, forming a highly exposed array of active sites; X-ray photoelectron spectroscopy analysis showed that cobalt in Co3S4 exists in a mixed valence state of +2 and +3, which is conducive to electron transfer and redox reactions; X-ray diffraction and Raman spectroscopy confirmed that Co3S4 has high crystallinity and an ordered structure.

[0012] The second objective of this invention is to protect the preparation method of the anodic functional material, which includes the following steps: (1) The nickel foam is ultrasonically cleaned and vacuum dried to obtain pretreated nickel foam; (2) Mix the graphene oxide dispersion with the thiourea solution, and then add the pretreated nickel foam obtained in step (1) for microwave reaction to reduce the graphene oxide and load it onto the surface of the nickel foam in a vertical arrangement to obtain rGO-NF; (3) Mix CoCl2 solution with thiourea solution, and then add rGO-NF obtained in step (2) for microwave reaction, so that Co3S4 nanosheets grow in situ and are arranged in an orderly manner on the surface of rGO-NF, thereby obtaining rGO@Co3S4-NF composite anode material.

[0013] Further, in step (1), the nickel foam is ultrasonically cleaned for 15 min each in acetone, hydrochloric acid solution, ethanol and ultrapure water.

[0014] Furthermore, the concentration of the hydrochloric acid solution is 3 mol / L.

[0015] Furthermore, in the mixed solution obtained in step (2), the concentration of graphene oxide is 8 mg / mL and the concentration of thiourea is 0.05 mol / L.

[0016] Furthermore, in the mixed solution obtained in step (3), the concentration of CoCl2 is 0.03 mol / L and the concentration of thiourea is 0.075 mol / L.

[0017] Furthermore, the microwave reactions described in steps (2) and (3) all adopt a two-step heating program, namely, first heating from room temperature to 70°C in 5 minutes, holding for 5 minutes, then heating to 110°C in 5 minutes, holding for 1 hour, and then cooling naturally.

[0018] A third objective of this invention is to protect the application of the aforementioned anode functional material.

[0019] Furthermore, the anolyte material can activate persulfate to generate singlet oxygen under the assistance of an electric field, thereby achieving the degradation of organic pollutants.

[0020] Furthermore, the electric field strength is 2-15 V, and the current density is 5-15 mA / cm². 2 .

[0021] Furthermore, the organic pollutants include tetracyclines, dyes, phenols, etc.

[0022] Furthermore, its application system has a pH range of 3-11 and can tolerate high concentrations of Cl. - Interference from anions such as SO4.

[0023] This invention uses nickel foam as a substrate, on which vertically aligned reduced graphene oxide and an ordered array of hexagonal Co3S4 nanosheets are sequentially loaded to form an rGO@Co3S4-NF composite structure. Under an electric field, negatively charged persulfate (PMS) migrates and accumulates directionally towards the anode, and is efficiently activated at the ordered Co3S4 active sites, thereby significantly promoting the conversion of free radicals to carbon dioxide. 1 O2 conversion.

[0024] The significant advantages of this invention are: (1) In terms of structure and performance: This invention constructs a unique hierarchical structure of “rGO vertical array@Co3S4 ordered hexagonal nanosheet array” on nickel foam through a two-step microwave method. Under the assistance of an electric field, the material of this invention can remove nearly 100% of tetracycline within 2.5 minutes, which is much faster than disordered Co3S4-NF (removal rate of ~32% after 30 minutes) and pure rGO-NF (removal rate of ~55% after 30 minutes). This ultra-fast degradation rate directly proves the significant advantage of its unique hierarchical structure in enhancing reaction kinetics.

[0025] (2) This invention is the first to combine "electric field-assisted PMS directional mass transfer" with "ordered structure catalyst". Molecular dynamics simulations show that the electric field drives the negatively charged PMS to accumulate at the anode, and significant accumulation of PMS on the anode surface can be achieved within 30 picoseconds, greatly increasing the local reactant concentration. The total system energy reaches equilibrium within 30 ps. After applying the electric field, the total system energy decreases, indicating that the electric field promotes the interaction between PMS and active sites. The interaction energy between PMS and Co3S4 increases from nearly 0 kcal / mol without an electric field to 30 kcal / mol under a 5 V electric field. At the same time, the highly ordered Co3S4 nanosheets provide sufficient active sites and high-efficiency electron transfer. Density functional theory calculations show that ordered large-size Co3S4 has a higher PMS adsorption energy (-3.49 eV vs -2.91 eV) and charge transfer capacity (0.755 e vs 0.723 e) than disordered small-size Co3S4, thus efficiently activating the enriched PMS. 1 O2. The O2-O2 bond length of PMS increased from the original 1.32 Å to 1.50 Å after contact with ordered Co3S4 (1.48 Å after contact with small-sized disordered Co3S4), indicating that the ordered structure is more conducive to the activation and bond breaking of PMS. This is a synergistic mechanism of "physical field-enhanced mass transfer" and "material structure optimization catalysis".

[0026] (3) Electron paramagnetic resonance (EPR) analysis shows that the material system of the present invention generates strong electromagnetic resonance under the action of an electric field. 1 O2 characteristic signal, when using TEMP trapping agent 1 O2 signal strength changes with current density from 5 mA / cm² 2 Increased to 15 mA / cm 2 The free radical signal is significantly enhanced, while there is almost no signal without an electric field; when using DMPO as a scavenger, the free radical signal is weak and almost undetectable. Free radical quenching experiments further confirm this. 1 O2 is the main active species in this system: the addition of methanol (quenches ·OH and SO4) - After adding ·), the removal rate remained above 80%; after adding isopropanol (quenching ·OH), the removal rate remained at 87%; and after adding L-histidine (quenching ·OH)... 1 After O2 removal, the removal rate dropped sharply to less than 20%. This proves that the present invention has successfully achieved the transition from the free radical pathway to the non-free radical pathway. 1 Regulation of the O2 pathway.

[0027] (4) The method of this invention utilizes microwave-assisted rapid synthesis under mild conditions, eliminating the need for high-temperature multi-step calcination or complex post-modification, resulting in a short material preparation cycle and low cost. Compared to catalysts that rely on complex electronic structure regulation, this invention uses simple materials and can achieve the desired results with the assistance of an electric field.1 The efficient and controllable generation of O2 has significant technological and economic advantages.

[0028] (5) The material of this invention maintains a pollutant removal rate of >94% over a wide pH range of 3-11, and is effective against high concentrations of Cl. - SO4 2- The material exhibits good resistance to anions. After five cycles of use, the degradation efficiency remains above 95%, demonstrating excellent stability and reusability.

[0029] In summary, this invention provides an anode material that is easy to prepare, has excellent performance, and a clear mechanism, as well as a scheme for singlet oxygen regulation using it. Through the synergy of "ordered structure" and "electric field assistance," it achieves... 1 The efficient and controllable generation of O2 is suitable for the rapid removal of recalcitrant organic pollutants in complex and highly saline industrial wastewater, demonstrating significant technological advancement and practical value. Attached Figure Description

[0030] Figure 1 The images shown are scanning electron microscope (SEM) images of the materials prepared in the examples and comparative examples 1-3.

[0031] Figure 2 The X-ray diffraction patterns are shown for the materials prepared in the examples and comparative examples 1-3.

[0032] Figure 3 The images show the Raman spectra of the materials prepared in the examples and comparative examples 1-3.

[0033] Figure 4 The figures show the contact angle test results of the materials prepared in the examples and comparative examples 1-3.

[0034] Figure 5 The X-ray photoelectron spectrum of rGO@Co3S4-NF prepared as an example.

[0035] Figure 6 This diagram illustrates the activation of persulfate to degrade tetracycline using rGO@Co3S4-NF prepared in the examples under different pH conditions with the aid of an electric field.

[0036] Figure 7 The diagram shows the degradation of tetracycline by persulfate using rGO@Co3S4-NF prepared in the examples under different electric field conditions.

[0037] Figure 8 The diagram shows the activation of persulfate to degrade tetracycline under different high-salt conditions using rGO@Co3S4-NF prepared in the examples under an electric field.

[0038] Figure 9This diagram illustrates the degradation of different pollutants by rGO@Co3S4-NF activated persulfate prepared in the examples under the assistance of an electric field.

[0039] Figure 10 The following are the electron paramagnetic resonance (EPR) experimental results of the materials prepared in Examples 1-3 and Comparative Examples 1-3, where a represents the signal of DMPO capturing free radicals, and b represents the signal of TEMP capturing free radicals. 1 The signal characteristics of O2, c represents the capture of O2 by the material in the example under different electric field strengths. 1 The signal status of O2.

[0040] Figure 11 The results of the free radical quenching experiment are shown for the materials prepared in the examples. Detailed Implementation

[0041] An anode functional material for the controllable generation of singlet oxygen assisted by an electric field, the preparation method of which includes the following steps: (1) The nickel foam was ultrasonically cleaned for 15 min each in acetone, 3 mol / L hydrochloric acid solution, ethanol and ultrapure water, and then vacuum dried to obtain pretreated nickel foam. (2) Prepare a mixed solution containing 8 mg / mL graphene oxide and 0.05 mol / L thiourea, then add the pretreated nickel foam obtained in step (1), and heat it from room temperature to 70°C in a microwave reactor for 5 min, hold for 5 min, then heat it to 110°C for 1 h, and then cool it naturally to reduce the graphene oxide and load it onto the surface of the nickel foam in a vertical arrangement to obtain rGO-NF; (3) Prepare a mixed solution containing 0.03 mol / L CoCl2 and 0.075 mol / L thiourea, and then add the rGO-NF obtained in step (2). In a microwave reactor, first raise the temperature from room temperature to 70℃ in 5 min, hold for 5 min, then raise the temperature to 110℃ in 5 min, hold for 1 h, and then cool naturally to allow Co3S4 nanosheets to grow in situ and arrange orderly on the surface of rGO-NF, thereby obtaining the rGO@Co3S4-NF composite anode material.

[0042] To make the content of this invention easier to understand, the technical solution of this invention will be further described below with reference to specific embodiments, but this invention is not limited thereto.

[0043] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods. Example

[0044] (1) Pretreatment of nickel foam: Nickel foam with a size of 1 cm × 2 cm was placed in acetone, 3 mol / L hydrochloric acid solution, anhydrous ethanol and ultrapure water respectively for ultrasonic cleaning for 15 minutes each, and then vacuum dried for later use.

[0045] (2) Preparation of rGO-NF: Prepare 10 mL of a mixed solution containing 8 mg / mL graphene oxide (GO) and 0.05 mol / L thiourea, put it into a microwave reaction tube, add a piece of pretreated nickel foam, place it in a microwave reactor, first raise the temperature from room temperature to 70℃ in 5 min, hold for 5 min, then raise the temperature to 110℃ in 5 min, hold for 60 min, and then cool naturally to obtain rGO-NF.

[0046] (3) Preparation of rGO@Co3S4-NF: Prepare 100 mL of a mixed solution containing 0.03 mol / L CoCl2 and 0.075 mol / L thiourea, dispense it into 10 microwave reaction tubes (10 mL per tube), add one piece of the above rGO-NF to each tube, place it in a microwave reactor, first raise the temperature from room temperature to 70℃ in 5 min, hold for 5 min, then raise the temperature to 110℃ in 5 min, hold for 60 min, and then cool naturally to obtain rGO@Co3S4-NF composite anode material.

[0047] Comparative Example 1 (1) Nickel foam pretreatment: Same as step (1) in Example 1; (2) The pretreated nickel foam (1 cm × 2 cm) was added to a mixed solution containing 0.03 mol / L CoCl2 and 0.075 mol / L thiourea, placed in a microwave reactor, and heated from room temperature to 70°C in 5 min, held for 5 min, then heated to 110°C in 5 min, held for 60 min, and then cooled naturally to obtain Co3S4-NF.

[0048] Comparative Example 2 (1) Nickel foam pretreatment: Same as step (1) in Example 1; (2) The pretreated nickel foam (1 cm × 2 cm) was added to 10 mL of a mixed solution containing 8 mg / mL graphene oxide (GO) and 0.05 mol / L thiourea. The solution was placed in a microwave reactor and heated from room temperature to 70°C in 5 min, held for 5 min, then heated to 110°C in 5 min, held for 60 min, and then cooled naturally to obtain rGO-NF.

[0049] Comparative Example 3 (1) Nickel foam pretreatment: Same as step (1) in Example 1; (2) The pretreated nickel foam (1 cm × 2 cm) was added to 10 mL of a mixed solution containing 8 mg / mL graphene oxide (GO) and 0.05 mol / L thiourea. The solution was placed in a microwave reactor and heated from room temperature to 70 °C in 5 min, held for 5 min, then heated to 110 °C in 30 min (slow heating), held for 60 min, and then cooled naturally to obtain rGO-NF.

[0050] (3) Preparation of GO@Co3S4-NF: Same as step (3) in Example 1.

[0051] In this comparative example, by adjusting the microwave reaction parameters, graphene oxide agglomerates during the reduction process, forming a horizontally stacked layered structure (rGO is not vertical). Co3S4 is randomly distributed on the surface of the horizontally stacked rGO, without a clear ordered array structure.

[0052] Comparative Example 4 (1) Nickel foam pretreatment: Same as step (1) in Example 1; (2) Preparation of rGO-NF: Same as step (2) in Example 1; (3) The pretreated nickel foam (1 cm × 2 cm) was added to a mixed solution containing 0.03 mol / L CoCl2 and 0.075 mol / L thiourea, and placed in a microwave reactor. The temperature was first increased from room temperature to 70°C in 5 min, held for 5 min, then increased to 110°C in 5 min, held for 10 min, and then cooled naturally to obtain rGO@Co3S4-NF composite anode material.

[0053] In this comparative example, the microwave reaction parameters were adjusted to induce insufficient growth of Co3S4 nuclei, thereby disrupting the ordered growth of Co3S4. SEM showed that Co3S4 appeared as randomly packed nanoparticles on the surface perpendicular to rGO, without a hexagonal ordered array. XRD showed that the characteristic peaks of Co3S4 were broadened and their intensity decreased, confirming its poor crystallinity and disordered structure.

[0054] Application Example 1 (1) Characterization of material morphology The prepared materials were systematically structurally characterized.

[0055] Depend on Figure 1The scanning electron microscope (SEM) images show that the original nickel foam has a three-dimensional porous structure with a smooth surface (a, e); in the Co3S4-NF prepared in Comparative Example 1, Co3S4 is directly loaded on the surface of the nickel foam, and therefore appears as randomly stacked nanoparticles with an irregular arrangement (b, f); in the rGO-NF prepared in Comparative Example 2, rGO has a vertically arranged sheet-like structure on the surface of the nickel foam (c, g); in the rGO@Co3S4-NF prepared in the example, Co3S4 grows in an orderly epitaxial manner along the vertical direction of rGO in the form of a hexagonal nanosheet array, forming a highly exposed array of active sites (d, h).

[0056] Depend on Figure 2 The X-ray diffraction (XRD) patterns show that all samples exhibit characteristic peaks of the Ni substrate at 44°, 52°, and 77°. Co3S4-NF and rGO@Co3S4-NF exhibit characteristic peaks of Co3S4 at 31.2°, 37.9°, 50.2°, and 55.3°, corresponding to the (311), (400), (511), and (440) crystal planes, respectively. Furthermore, the characteristic peak intensity of Co3S4 grown with rGO as a template (Example) is significantly higher than that of directly grown Co3S4 (Comparative Example 1), indicating that it has higher crystallinity and a more ordered structure.

[0057] Depend on Figure 3 The given Raman spectrum shows that rGO-NF at 1350 cm⁻¹ -1 and 1580 cm -1 The presence of D and G peaks at 500 cm⁻¹ corresponds to the characteristics of carbon materials. However, in rGO@Co₃S₄-NF, the signal of rGO is masked due to the Co₃S₄ loading on the rGO surface. -1 The following shows the Eg, F2g, and A1g vibrational peaks of Co3S4, and the peak intensity and resolution are significantly higher than those of Co3S4-NF, confirming its higher crystallinity.

[0058] Depend on Figure 4 The contact angle test results show that the original nickel foam is hydrophobic (contact angle 100°-103°), while rGO-NF and rGO@Co3S4-NF are hydrophilic (contact angle <90°), which is beneficial for electrode-solution contact.

[0059] Figure 5 The X-ray photoelectron spectroscopy (XPS) spectrum of rGO@Co3S4-NF clearly shows the characteristic peaks of Co, S, O, and C (a); C 1s spectrum: 284.79 eV (CC), 286.9 eV (CS), 288.9 eV (C=O), confirming the formation of CS bonds (b); S 2p spectrum: 163.2 eV (S 2p... 1 / 2), 161.5 eV (S 2p) 3 / 2 ), and SO at 168.5 eV and 166.2 eV. x n- Peak (c); Co 2p spectrum: 780.8 eV and 796.5 eV correspond to Co 2+ 782.3 eV and 797.9 eV correspond to Co 3+ This confirms that cobalt exists in a mixed valence state of +2 and +3, which is conducive to electron transfer (d).

[0060] (2) Electrocatalytic degradation performance test The rGO@Co3S4-NF obtained in Example 1 was used as the anode in a 100 mL electrolytic cell for tetracycline (TC) degradation experiments. The reaction conditions were: initial TC concentration 20 mg / L, solution volume 50 mL, pH=7.0 (unadjusted), and anode working area 4 cm². 2 (Double-sided), with a platinum plate as the counter electrode, and 0.5 mM persulfate (PMS) added to the electrolytic cell. Samples were taken at intervals, and the concentration of total chloride (TC) was determined by high-performance liquid chromatography (HPLC). Current densities of 0, 5, 10, 15, and 25 mA / cm² were tested. 2 The degradation effect at that time. Results are shown in... Figure 6 .

[0061] Figure 6 The results showed that the current density was 0 mA / cm². 2 At that time, the removal rate was approximately 60% after 30 minutes; the current density was 5 mA / cm². 2 At that time, the removal rate reached 99.2% in 2.5 minutes; the current density was 10 mA / cm². 2 At that time, a removal rate of 90.7% was achieved in just 0.5 minutes, and nearly 100% was achieved in 2.5 minutes; the current density was 15 mA / cm². 2 At 2.5 minutes, the removal rate reached 99.5%; the current density was increased to 25 mA / cm². 2 At this point, the degradation efficiency may decrease to 95% due to increased side reactions (such as oxygen evolution and ineffective PMS decomposition). (Note: 5-15 mA / cm) 2 This is the optimal working range for this system.

[0062] The degradation performance of TC by different morphological materials prepared in the examples and comparative examples was further investigated. The reaction conditions were: initial TC concentration 20 mg / L, solution volume 50 mL, pH=7.0 (unadjusted), and anolyte working area 4 cm². 2 (Double-sided), with a platinum plate as the counter electrode, and a current density of 5 mA / cm². 2The PMS dosage was 0.25 mM. Samples were taken at intervals, and the TC concentration was determined by high-performance liquid chromatography.

[0063] Table 1 Comparison of tetracycline degradation performance of materials with different morphologies

[0064] The results in Table 1 show that: 1) The degradation efficiency of directly loading disordered Co3S4 (Comparative Example 1) or simple rGO (Comparative Example 2) onto nickel foam is limited (removal rate of 32.1%-55.4% in 30 min). 2) When the vertical structure of rGO was destroyed (Comparative Example 3) or the ordered structure of Co3S4 was destroyed (Comparative Example 4), the removal rate at 2.5 min dropped to 41.5% and 53.7%, respectively, proving that the vertical arrangement of rGO is a prerequisite for inducing the ordered growth of Co3S4, and the ordered hexagonal array of Co3S4 is crucial for performance improvement. 3) rGO@Co3S4-NF (Example 1) exhibits significantly faster degradation rate and higher removal efficiency. The TC removal rate reaches 99.2% within 2.5 minutes and 100% after 30 minutes of reaction, with a total organic carbon (TOC) removal rate of 91.5%. Furthermore, it has been verified that the TC degradation efficiency remains above 95% after 5 cycles of use, demonstrating its excellent stability. This is attributed to the abundant active sites exposed by its ordered structure, efficient electron transport, and the directional enrichment and activation of PMS under electric field assistance.

[0065] The above comparison fully demonstrates that the present invention produces a synergistic effect through the specific morphological combination of "vertical rGO array" and "ordered Co3S4 hexagonal nanosheets". The vertical rGO provides a template for ordered growth and a fast electron transport channel, while the ordered Co3S4 array maximizes the exposure of active sites and promotes the efficient activation of PMS. The two work together to achieve efficient and controllable generation of singlet oxygen.

[0066] Application Example 2 The degradation performance of the materials prepared in the examples on TC under different pH conditions was investigated. The reaction conditions were: initial TC concentration 10 mg / L, solution volume 50 mL, and current density 10 mA / cm². 2 The PMS dosage was 0.5 mM. Results are shown below. Figure 7 .

[0067] Figure 7 The results showed that the material maintained a tetracycline removal rate of over 94% within a pH range of 3-9 (adjusted with HCl or NaOH), demonstrating its wide pH adaptability.

[0068] Application Example 3 The resistance of the materials prepared in the examples to ionic interference in various saline wastewaters was investigated. The reaction conditions were: initial TC concentration 10 mg / L, solution volume 50 mL, pH=5.0, and current density 10 mA / cm². 2 The PMS dosage was 0.5 mM, and 20 mM NaCl, Na₂SO₄, NaNO₃, and Na₂CO₃ were added to the reaction solution respectively (to simulate high-salt wastewater in different scenarios). Results are shown below. Figure 8 .

[0069] Figure 8 The results showed that the material could achieve nearly 100% TC removal in various high-salinity wastewaters, indicating that the material has excellent tolerance to various high-salinity wastewaters.

[0070] Application Example 4 The degradation effects of the materials prepared in the examples on different pollutants were investigated. The reaction conditions were: initial pollutant concentration of 20 mg / L (Rhodamine B (RhB), pyridine (Py), vanillin (VL), bisphenol A (BPA), furosemide (FM)), solution volume of 50 mL, pH = 9.0, and current density of 15 mA / cm². 2 The PMS dosage was 0.75 mM. Results are shown below. Figure 9 .

[0071] like Figure 9 The results showed that the material can achieve nearly 100% removal of various pollutants. Example 2

[0072] (1) Electron paramagnetic resonance (EPR) analysis At current densities of 0, 5, 10, and 15 mA / cm 2 Below, using 5,5-dimethyl-1-pyrrolline-N-oxide (DMPO) and 2,2,6,6-tetramethylpiperidine (TEMP) as scavengers, the free radicals and singlet oxygen in the reaction system of different materials were detected. 1 O2), results are shown in Figure 10 .

[0073] Figure 10 The results showed that when using DMPO to capture free radicals, no obvious free radical signal was detected in any sample (a); when using TEMP to capture free radicals... 1 At O2, only rGO@Co3S4-NF showed a significant signal, and this signal was only detected at a current density of 15 mA / cm². 2 The signal is most significant at time (b, c), indicating that 1 O2 is the main active species, and its generation is enhanced by an electric field. The signal strength is positively correlated with the current density.

[0074] (2) Free radical quenching experiment Excess methanol (to quench OH and SO4) was added to the degradation system, respectively. - ·), isopropanol (quenching ·OH) and L-histidine (quenching) 1 O2). For example Figure 11 The results showed that the TC removal rate remained above 80% after the addition of methanol; the TC removal rate remained at 87% after the addition of isopropanol; and the TC removal rate dropped sharply to less than 20% after the addition of L-histidine, further confirming... 1 The dominant role of O2.

[0075] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention should be included in the scope of the present invention.

Claims

1. An anodic functional material for the controlled generation of singlet oxygen assisted by an electric field, characterized in that: The anodic functional material is based on nickel foam, on which vertically arranged reduced graphene oxide and ordered Co3S4 nanosheets are sequentially loaded to form an rGO@Co3S4-NF composite structure.

2. A method for preparing the anode functional material as described in claim 1, characterized in that, Includes the following steps: (1) The nickel foam is ultrasonically cleaned and vacuum dried to obtain pretreated nickel foam; (2) Mix the graphene oxide dispersion with the thiourea solution, and then add the pretreated nickel foam obtained in step (1) for microwave reaction to reduce the graphene oxide and load it onto the surface of the nickel foam in a vertical arrangement to obtain rGO-NF; (3) Mix CoCl2 solution with thiourea solution, and then add rGO-NF obtained in step (2) for microwave reaction, so that Co3S4 nanosheets grow epitaxially along the direction perpendicular to the reduced graphene oxide to form an ordered array of hexagonal nanosheets, thereby obtaining rGO@Co3S4-NF composite anode material.

3. The preparation method according to claim 2, characterized in that: In the mixed solution obtained in step (2), the concentration of graphene oxide is 8 mg / mL and the concentration of thiourea is 0.05 mol / L.

4. The preparation method according to claim 2, characterized in that: In the mixed solution obtained in step (3), the concentration of CoCl2 is 0.03 mol / L and the concentration of thiourea is 0.075 mol / L.

5. The preparation method according to claim 2, characterized in that: The microwave reactions described in steps (2) and (3) all employ a two-step heating procedure: first, the temperature is increased from room temperature to 70°C in 5 minutes, held for 5 minutes, then increased to 110°C in 5 minutes, held for 1 hour, and then cooled naturally.

6. An application of the anodic functional material as described in claim 1 in the electric field-assisted degradation of organic pollutants, characterized in that, The anolyte material can activate persulfate to generate singlet oxygen under the assistance of an electric field, thereby degrading organic pollutants.

7. The application according to claim 6, characterized in that: The electric field strength is 2-15 V, and the current density is 5-15 mA / cm². 2 .

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