Iron single-atom catalyst for efficient degradation of fluoroquinolone antibiotics and defluorination and application thereof

Abstract

The application discloses a kind of iron monatomic catalysts with high efficiency in degrading fluoroquinolone antibiotics and defluorination and application thereof.The application realizes controllable preparation of iron monatomic catalysts with different sulfur coordination by changing the complexation between sulfur-containing ligand and iron ion.The removal of high-energy carbon-fluorine bond is the key and difficulty of fluoroquinolone antibiotic degradation, and the regulation of iron electron-rich region / sulfur electron-deficient region can promote the efficient occurrence of electron transfer process, which is beneficial to the rupture of carbon-fluorine bond.The iron monatomic catalyst prepared by the method has good degradation effect and defluorination efficiency for various fluoroquinolone antibiotics.

Description

Technical Field

[0001] This invention belongs to the field of materials engineering and environmental engineering technology, specifically relating to an iron single-atom catalyst for the efficient degradation and defluorination of fluoroquinolone antibiotics and its application. Background Technology

[0002] my country produces a large quantity of antibiotics annually and has a huge demand for them. Fluoroquinolone antibiotics, such as norfloxacin and ciprofloxacin, are widely used in the pharmaceutical and aquaculture industries due to their unique molecular structures containing valence groups (such as -F, piperazine ring, cyclopropyl, and hydroxyl groups), which exhibit broad antibacterial spectrum and strong antibacterial activity. However, the lack of green, economical, and efficient wastewater treatment technologies for fluoroquinolone antibiotics easily leads to the emergence of drug-resistant bacteria and the spread of resistance genes, threatening human health and environmental safety. Therefore, there is an urgent need to develop efficient degradation and defluorination technologies for fluoroquinolone antibiotic wastewater.

[0003] Traditional advanced oxidation processes (AEs) suffer from low utilization of target active species and difficulty in controlling electron transfer (ET) processes, resulting in poor efficacy in treating fluoroquinolone antibiotics and their high-bond-energy carbon-fluorine bonds. Iron single-atom catalysts (Fe SACs) can efficiently remove antibiotics in AEs. However, the structure-activity relationship between the metal atom loading of single-atom catalysts (SACs) and their activity and selectivity is unclear. By leveraging the synergistic effect of individual metal atoms and coordinating atoms, atom utilization can be improved to achieve high activity. Highly uniform active sites and geometric configurations enable energy level matching, achieving highly selective generation of active species (such as ETs). Precise design of electron-rich / electron-deficient regions within the SAC can enhance sp... 2 By optimizing the carbon content and addressing the poor conductivity of the carrier, the electron transfer process between persulfate (PMS, PDS) and organic pollutants is directionally controlled, thereby achieving efficient degradation and defluorination processes.

[0004] A hydrogen-bonded self-assembly coupled hydrothermal strategy enables the precise preparation of highly loaded iron single-atom catalysts with sulfur (S) atom coordination. The S coordination activates PMS at the highly loaded iron (Fe) sites to generate singlet oxygen (…). 1 O2 and PDS play a regulatory role in processes such as electrochemical oxidation (ET). The Fe electron-rich region / S electron-deficient region not only serves as a catalytic site, improving PDS utilization, but also accelerates electron transfer within the support, facilitating the breaking of high-bond-energy carbon-fluorine bonds. Therefore, utilizing S atom coordination and sp... 2 Using carbon-supported iron single-atom catalysts to activate persulfate-enhanced ET processes is a key technology for achieving defluorination of fluoroquinolone antibiotics. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by providing an iron single-atom catalyst for the efficient degradation and defluorination of fluoroquinolone antibiotics and its applications.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] In a first aspect, the present invention provides an iron single-atom catalyst for the efficient degradation and defluorination of fluoroquinolone antibiotics, wherein the iron single-atom catalyst for the efficient degradation and defluorination of fluoroquinolone antibiotics is prepared by the following steps:

[0008] (1) Dissolve 0.25–0.35 g of oxalic acid and 0.25–0.35 g of ferric nitrate nonahydrate in 30–40 mL of deionized water to obtain solution A; while magnetically stirring at 85–90 °C, dissolve 0.8–0.9 g of cyanuric acid in 90–100 mL of deionized water to obtain cyanuric acid solution, then slowly add solution A to the cyanuric acid solution and mix thoroughly to obtain solution B; while magnetically stirring at 85–90 °C, dissolve 0.9–1.0 g of melamine in 100–110 mL of deionized water to obtain melamine solution, then slowly add the melamine solution to solution B and continue magnetically stirring for 4–5 h to obtain solution C; then filter solution C to obtain supramolecular precursor;

[0009] (2) The supramolecular precursor was washed several times with deionized water and then dried at 55-65℃ for 12-16h. The dried supramolecular precursor was then placed in a tube furnace and heated to 550-650℃ at a heating rate of 4-6℃ / min under flowing argon for 4-5h. After natural cooling, it was taken out to obtain Fe1 / CN.

[0010] (3) Add the Fe1 / CN prepared in step (2), 4.3-4.4 g of glucose and 30-40 mL of ultrapure water into the inner liner of the reactor. After assembling the reactor, place it in an oven and heat it at 170-190℃ for 10-11 h. Then filter it. Dry the filtered solid at 55-65℃ for 12-16 h. Place it in a tube furnace and heat it to 800-1000℃ at a heating rate of 4-6℃ / min under flowing argon for 4-5 h. After natural cooling, obtain an iron single-atom catalyst that efficiently degrades and defluorinates fluoroquinolone antibiotics, denoted as Fe1 / NC.

[0011] Secondly, the present invention provides an iron single-atom catalyst for the efficient degradation and defluorination of fluoroquinolone antibiotics, wherein the iron single-atom catalyst for the efficient degradation and defluorination of fluoroquinolone antibiotics is prepared by the following steps:

[0012] (1) Dissolve 0.05–0.1 g of ferric citrate and 0.07–0.13 g of N-allyl thiourea in 30–40 mL of deionized water to obtain solution A; while magnetically stirring at 85–90 °C, dissolve 0.8–0.9 g of cyanuric acid in 90–100 mL of deionized water to obtain cyanuric acid solution, then slowly add solution A to the cyanuric acid solution and mix thoroughly to obtain solution B; while magnetically stirring at 85–90 °C, dissolve 0.9–1.0 g of melamine in 100–110 mL of deionized water to obtain melamine solution, then slowly add the melamine solution to solution B and continue magnetically stirring for 4–5 h to obtain solution C; then filter solution C to obtain supramolecular precursor;

[0013] (2) The supramolecular precursor was washed several times with deionized water and then dried at 55-65℃ for 12-16h. The dried supramolecular precursor was then placed in a tube furnace and heated to 550-650℃ at a heating rate of 4-6℃ / min under flowing argon for 4-5h. After natural cooling, it was taken out to obtain Fe1S / CN.

[0014] (3) Add the Fe1S / CN prepared in step (2), 4.3-4.4 g of glucose and 30-40 mL of ultrapure water into the inner liner of the reactor. After assembling the reactor, place it in an oven and heat it at 170-190℃ for 10-11 h. Then filter it. Dry the filtered solid at 55-65℃ for 12-16 h. Place it in a tube furnace and heat it to 800-1000℃ at a heating rate of 4-6℃ / min under flowing argon for 4-5 h. After natural cooling, a highly efficient iron single-atom catalyst for degrading and defluorinating fluoroquinolone antibiotics is obtained, denoted as Fe1S / NC.

[0015] Thirdly, the present invention provides an iron single-atom catalyst for the efficient degradation and defluorination of fluoroquinolone antibiotics, wherein the iron single-atom catalyst for the efficient degradation and defluorination of fluoroquinolone antibiotics is prepared by the following steps:

[0016] (1) Dissolve 0.6-0.7g of ferric citrate and 0.15-0.25g of thiocyanate in 30-40mL of deionized water to obtain solution A; while magnetically stirring at 85-90℃, dissolve 0.8-0.9g of cyanuric acid in 90-100mL of deionized water to obtain cyanuric acid solution, then slowly add solution A to the cyanuric acid solution and mix thoroughly to obtain solution B; while magnetically stirring at 85-90℃, dissolve 0.9-1.0g of melamine in 100-110mL of deionized water to obtain melamine solution, then slowly add the melamine solution to solution B and continue magnetic stirring for 4-5h to obtain solution C; then filter solution C to obtain supramolecular precursor;

[0017] (2) The supramolecular precursor was washed several times with deionized water and then dried at 55-65℃ for 12-16h. The dried supramolecular precursor was then placed in a tube furnace and heated to 550-650℃ at a heating rate of 4-6℃ / min under flowing argon for 4-5h. After natural cooling, it was taken out to obtain Fe1 / SCN.

[0018] (3) Add the Fe1 / SCN prepared in step (2), 4.3-4.4 g of glucose and 30-40 mL of ultrapure water into the inner liner of the reactor. After assembling the reactor, place it in an oven and heat it at 170-190℃ for 10-11 h. Then filter it. Dry the filtered solid at 55-65℃ for 12-16 h. Place it in a tube furnace and heat it to 800-1000℃ at a heating rate of 4-6℃ / min under flowing argon for 4-5 h. After natural cooling, obtain an iron single-atom catalyst that efficiently degrades and defluorinates fluoroquinolone antibiotics, denoted as Fe1 / SNC.

[0019] Fourthly, this invention provides the application of a highly efficient iron single-atom catalyst for degrading and defluorinating fluoroquinolone antibiotics in the removal of fluoroquinolone antibiotics from water, comprising the following steps: adding the highly efficient iron single-atom catalyst for degrading and defluorinating fluoroquinolone antibiotics to water containing fluoroquinolone antibiotics, magnetically stirring to obtain a mixed solution, and after adsorption equilibrium for 25-35 minutes, adding persulfate (PMS, PDS), activating and degrading for 4-5 hours to complete the removal of fluoroquinolone antibiotics from the water; the dosage of the fluoroquinolone antibiotics is 0.1-0.3 g / L; the dosage of the highly efficient iron single-atom catalyst for degrading and defluorinating fluoroquinolone antibiotics is 0.02-0.08 mM; and the dosage of the persulfate is 1-3 mM.

[0020] Furthermore, the fluoroquinolone antibiotic is ciprofloxacin, norfloxacin, moxifloxacin, pazufloxacin, or gatifloxacin.

[0021] Furthermore, the persulfate is a permonosulfate or a perdisulfate.

[0022] The beneficial effects of this invention are:

[0023] 1) By regulating the added ligands, controllable preparation of different S coordination sites was achieved, thereby precisely controlling the activation of PMS generation at high Fe loading sites. 1 O2 and PDS undergo electron transfer (ET);

[0024] 2) By utilizing the presence of the Fe electron-rich region / S electron-deficient region, the PDS activation pathway can be modulated to improve PDS utilization and sp 2The carbon support has good electrical conductivity, and the Fe and S sites form a huge potential difference. Fe1S / NC and Fe1 / SNC mainly activate PDS to generate ET, which is conducive to the breaking of carbon-fluorine bonds. By removing high bond energy carbon-fluorine bonds and their valence groups, the efficient degradation of fluoroquinolone antibiotics is promoted. Attached Figure Description

[0025] Figure 1 These are aberration-corrected high-angle annular dark-field scanning transmission electron microscope images and elemental distribution spectra of Fe, S, C, and N for the iron single-atom catalysts prepared in Examples 1, 2, and 3. Figure 1 (a) is a high-angle annular dark-field scanning transmission electron microscope image of the iron single-atom catalyst prepared in Example 1 with spherical aberration correction and the elemental distribution spectra of Fe, S, C, and N. Figure 1 (b) is a high-angle annular dark-field scanning transmission electron microscope image of the iron single-atom catalyst prepared in Example 2, corrected for spherical aberration, and the elemental distribution spectra of Fe, S, C, and N. Figure 1 (c) is a high-angle annular dark-field scanning transmission electron microscope image of the iron single-atom catalyst prepared in Example 3 with spherical aberration correction and the elemental distribution spectrum of Fe, S, C and N.

[0026] Figure 2 The X-ray diffraction patterns of the iron single-atom catalysts prepared in Examples 1, 2 and 3 and NC are shown.

[0027] Figure 3 The following are the Fe K-edge X-ray absorption near-edge structure spectra of the iron single-atom catalysts, FeO, Fe2O3, and Fe3O4 prepared in Examples 1, 2, and 3;

[0028] Figure 4 Fourier transform R-space X-ray extended edge absorption fine structure spectra of the Fe K-side of the iron single-atom catalyst, FeS, Fe3N, Fe4N, and iron foil prepared in Examples 1, 2, and 3.

[0029] Figure 5 The graph shows the concentration change of CIP during the degradation of CIP by different concentrations of PMS or PDS activated by the iron single-atom catalyst prepared in Example 3. Figure 5 (a) is a graph showing the concentration change of CIP during the degradation of CIP by PMS at different concentrations using the iron single-atom catalyst prepared in Example 3. Figure 5 (b) is a graph showing the concentration change of CIP during the degradation of CIP by PDS with different concentrations of iron single-atom catalyst prepared in Example 3.

[0030] Figure 6The degradation rate diagram is shown for the degradation of CIP by the iron single-atom catalyst prepared in Example 3, which activates different concentrations of PMS or PDS.

[0031] Figure 7 The graph shows the change of CIP concentration over time during the degradation of CIP by PDS or PDS alone using the iron single-atom catalyst, NC, and SNC activated by PDS or PDS alone, prepared in Examples 1, 2, and 3.

[0032] Figure 8 The graph shows the change of defluorination rate over time during the degradation of CIP by iron single-atom catalysts, NC, and SNC-activated PDS or PDS-only CIP prepared in Examples 1, 2, and 3.

[0033] Figure 9 The graph shows the degradation rate and final defluorination rate of the iron single-atom catalyst, NC, and SNC activated PDS during the degradation of CIP prepared in Examples 1, 2, and 3.

[0034] Figure 10 The graph shows the degradation rate and final defluorination rate of the iron single-atom catalyst, NC, and SNC activated PMS during the degradation of CIP prepared in Examples 1, 2, and 3.

[0035] Figure 11 The contribution rates of various active species generated during the degradation of CIP by the iron single-atom catalyst, NC, and SNC-activated PMS prepared in Examples 1, 2, and 3 to the degradation of CIP;

[0036] Figure 12 The graphs show the changes in NOx concentration and defluorination rate over time during the NOx degradation process of NC-activated PDS by the iron single-atom catalysts prepared in Examples 1, 2, and 3. Figure 12 (a) is a graph showing the change of NOx concentration over time during the NOx degradation process of NC-activated PDS using iron single-atom catalysts prepared in Examples 1, 2, and 3. Figure 12 (b) is a graph showing the change of defluorination rate over time during the NOx degradation process of the iron single-atom catalysts prepared in Examples 1, 2 and 3 and NC-activated PDS.

[0037] Figure 13 The graphs show the iron single-atom catalysts prepared in Examples 1, 2, and 3, and the changes in MOX concentration and defluorination rate over time during the MOX degradation process of NC-activated PDS. Figure 13 (a) shows the iron single-atom catalysts prepared in Examples 1, 2, and 3, and the change of MOX concentration over time during the degradation of MOX by NC-activated PDS. Figure 13 (b) shows the iron single-atom catalysts prepared in Examples 1, 2 and 3, and the change of defluorination rate over time during the degradation of MOX by NC-activated PDS;

[0038] Figure 14 The graphs show the iron single-atom catalysts prepared in Examples 1, 2, and 3, and the changes in PAZ concentration and defluorination rate over time during the degradation of PAZ by NC-activated PDS. Figure 14 (a) shows the iron single-atom catalysts prepared in Examples 1, 2, and 3, and the change of PAZ concentration over time during the degradation of PAZ by NC-activated PDS. Figure 14 (b) shows the iron single-atom catalysts prepared in Examples 1, 2 and 3, and the change of defluorination rate over time during the degradation of PAZ by NC-activated PDS;

[0039] Figure 15 The graphs show the changes in GAT concentration and defluorination rate over time during the degradation of GAT by NC-activated PDS using iron single-atom catalysts prepared in Examples 1, 2, and 3, as well as the changes in GAT concentration and defluorination rate over time. Figure 15 (a) is a graph showing the change of GAT concentration over time during the degradation of GAT by NC-activated PDS using iron single-atom catalysts prepared in Examples 1, 2, and 3. Figure 15 (b) is a graph showing the change of defluorination rate over time during the degradation of GAT by NC-activated PDS using iron single-atom catalysts prepared in Examples 1, 2 and 3;

[0040] Figure 16 The graphs show the degradation rates of various fluoroquinolone antibiotics during the degradation of the iron single-atom catalysts prepared in Examples 1, 2, and 3, and the degradation process of various fluoroquinolone antibiotics by NC-activated PDS.

[0041] Figure 17 The graph shows the dechlorination rate of the iron single-atom catalysts prepared in Examples 1, 2 and 3, and the degradation of various fluoroquinolone antibiotics by NC-activated PDS. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention.

[0043] This invention provides a method for preparing an iron single-atom catalyst that efficiently degrades and defluorinates fluoroquinolone antibiotics, comprising the following steps:

[0044] (1) Dissolve 0.25–0.35 g of oxalic acid and 0.25–0.35 g of ferric nitrate nonahydrate in 30–40 mL of deionized water to obtain solution A; while magnetically stirring at 85–90 °C, dissolve 0.8–0.9 g of cyanuric acid in 90–100 mL of deionized water to obtain cyanuric acid solution, then slowly add solution A to the cyanuric acid solution and mix thoroughly to obtain solution B; while magnetically stirring at 85–90 °C, dissolve 0.9–1.0 g of melamine in 100–110 mL of deionized water to obtain melamine solution, then slowly add the melamine solution to solution B and continue magnetically stirring for 4–5 h to obtain solution C, so that iron atoms are fixed on the carrier along with the organic ligands; then filter solution C to obtain the supramolecular precursor.

[0045] (2) The supramolecular precursor was washed several times with deionized water and then dried at 55-65°C for 12-16 h. The dried supramolecular precursor was then placed in a tube furnace and heated to 550-650°C at a heating rate of 4-6°C / min under flowing argon for 4-5 h. After natural cooling, it was taken out to obtain Fe1 / CN, at which point the support was graphitic carbon nitride.

[0046] (3) Add the Fe1 / CN prepared in step (2), 4.3-4.4 g of glucose and 30-40 mL of ultrapure water into the inner liner of the reactor. After assembling the reactor, place it in an oven and heat it at 170-190℃ for 10-11 h. Then filter it. Dry the filtered solid at 55-65℃ for 12-16 h. Place it in a tube furnace and heat it to 800-1000℃ at a heating rate of 4-6℃ / min under flowing argon for 4-5 h. After natural cooling, obtain an iron single-atom catalyst that efficiently degrades and defluorinates fluoroquinolone antibiotics, denoted as Fe1 / NC. At this time, the support is nitrogen (N) doped carbon (C).

[0047] This invention also provides a second method for preparing a highly efficient iron single-atom catalyst for degrading and defluorinating fluoroquinolone antibiotics, comprising the following steps:

[0048] (1) Dissolve 0.05-0.1g of ferric citrate and 0.07-0.13g of N-allyl thiourea in 30-40mL of deionized water to obtain solution A; while magnetically stirring at 85-90℃, dissolve 0.8-0.9g of cyanuric acid in 90-100mL of deionized water to obtain cyanuric acid solution, then slowly add solution A to the cyanuric acid solution and mix thoroughly to obtain solution B; while magnetically stirring at 85-90℃, dissolve 0.9-1.0g of melamine in 100-110mL of deionized water to obtain melamine solution, then slowly add the melamine solution to solution B and continue magnetic stirring for 4-5h to obtain solution C, so that iron atoms are fixed on the support along with the organic ligands; then filter solution C to obtain supramolecular precursor.

[0049] (2) The supramolecular precursor was washed several times with deionized water and then dried at 55-65°C for 12-16 h. The dried supramolecular precursor was then placed in a tube furnace and heated to 550-650°C at a heating rate of 4-6°C / min under flowing argon for 4-5 h. After natural cooling, it was taken out to obtain Fe1S / CN, at which point the support was graphitic carbon nitride.

[0050] (3) Add the Fe1S / CN prepared in step (2), 4.3-4.4 g of glucose and 30-40 mL of ultrapure water into the inner liner of the reactor. After assembling the reactor, place it in an oven and heat it at 170-190℃ for 10-11 h. Then filter it. Dry the filtered solid at 55-65℃ for 12-16 h. Place it in a tube furnace and heat it to 800-1000℃ at a heating rate of 4-6℃ / min under flowing argon for 4-5 h. After natural cooling, obtain an iron single-atom catalyst that efficiently degrades and defluorinates fluoroquinolone antibiotics, denoted as Fe1S / NC. At this time, the support is N-doped C.

[0051] This invention also provides a third method for preparing a highly efficient iron single-atom catalyst for degrading and defluorinating fluoroquinolone antibiotics, comprising the following steps:

[0052] (1) Dissolve 0.6-0.7g of ferric citrate and 0.15-0.25g of thiocyanate in 30-40mL of deionized water to obtain solution A; while magnetically stirring at 85-90℃, dissolve 0.8-0.9g of cyanuric acid in 90-100mL of deionized water to obtain cyanuric acid solution, then slowly add solution A to the cyanuric acid solution and mix thoroughly to obtain solution B; while magnetically stirring at 85-90℃, dissolve 0.9-1.0g of melamine in 100-110mL of deionized water to obtain melamine solution, then slowly add the melamine solution to solution B and continue magnetic stirring for 4-5h to obtain solution C, so that iron atoms are fixed on the support along with the organic ligands; then filter solution C to obtain supramolecular precursor.

[0053] (2) The supramolecular precursor was washed several times with deionized water and then dried at 55-65℃ for 12-16h. The dried supramolecular precursor was then placed in a tube furnace and heated to 550-650℃ for 4-5h under flowing argon at a heating rate of 4-6℃ / min. After natural cooling, it was taken out to obtain Fe1 / SCN, at which point the support was graphitic carbon nitride.

[0054] (3) Add the Fe1 / SCN prepared in step (2), 4.3-4.4 g of glucose and 30-40 mL of ultrapure water into the inner liner of the reactor. After assembling the reactor, place it in an oven and heat it at 170-190℃ for 10-11 h. Then filter it. Dry the filtered solid at 55-65℃ for 12-16 h. Place it in a tube furnace and heat it to 800-1000℃ at a heating rate of 4-6℃ / min under flowing argon for 4-5 h. After natural cooling, obtain an iron single-atom catalyst that efficiently degrades and defluorinates fluoroquinolone antibiotics, denoted as Fe1 / SNC. At this time, the support is N-doped C.

[0055] This invention also provides the application of a highly efficient iron single-atom catalyst for degrading and defluorinating fluoroquinolone antibiotics in the removal of fluoroquinolone antibiotics from water, comprising the following steps: adding the highly efficient iron single-atom catalyst for degrading and defluorinating fluoroquinolone antibiotics to water containing fluoroquinolone antibiotics, magnetically stirring to obtain a mixed solution, and after adsorption equilibrium for 25-35 min, adding persulfate, and activating degradation for 4-5 h to complete the removal of fluoroquinolone antibiotics from the water; the dosage of the fluoroquinolone antibiotics is 0.1-0.3 g / L; the dosage of the highly efficient iron single-atom catalyst for degrading and defluorinating fluoroquinolone antibiotics is 0.02-0.08 mM; and the dosage of persulfate is 1-3 mM.

[0056] The fluoroquinolone antibiotics mentioned are ciprofloxacin (CIP), norfloxacin (NOX), moxifloxacin (MOX), pazufloxacin (PAZ), or gatifloxacin (GAT).

[0057] The persulfate is permonosulfate (PMS) or perdisulfate (PDS).

[0058] Example 1: An efficient iron single-atom catalyst (Fe1 / NC) for the degradation and defluorination of fluoroquinolone antibiotics was prepared through the following steps:

[0059] (1) Dissolve 0.29 g of oxalic acid and 0.32 g of ferric nitrate nonahydrate in 30 mL of deionized water to obtain solution A; while stirring magnetically at 85 °C, dissolve 0.83 g of cyanuric acid in 90 mL of deionized water to obtain cyanuric acid solution. Then slowly add solution A to the cyanuric acid solution and mix thoroughly to obtain solution B; while stirring magnetically at 85 °C, dissolve 1.0 g of melamine in 100 mL of deionized water to obtain melamine solution. Then slowly add the melamine solution to solution B and continue stirring magnetically for 4 h to obtain solution C; then filter solution C to obtain supramolecular precursor.

[0060] (2) The supramolecular precursor was washed several times with deionized water and then dried at 60°C for 14 h. The dried supramolecular precursor was then placed in a tube furnace and heated to 600°C at a heating rate of 5°C / min under flowing argon for 4 h. After natural cooling, it was taken out to obtain Fe1 / CN.

[0061] (3) Add the Fe1 / CN prepared in step (2), 4.32 g of glucose, and 35 mL of ultrapure water to the inner liner of the reactor. After assembling the reactor, place it in an oven and heat it at 180°C for 10 h for filtration. Dry the filtered solid at 60°C for 14 h. Place it in a tube furnace and heat it to 900°C at a heating rate of 5°C / min under flowing argon for 4 h. After natural cooling, obtain a highly efficient iron single-atom catalyst for degrading and defluorinating fluoroquinolone antibiotics, denoted as Fe1 / NC.

[0062] Example 2: An efficient iron single-atom catalyst (Fe1S / NC) for the degradation and defluorination of fluoroquinolone antibiotics was prepared through the following steps:

[0063] (1) Dissolve 0.07g of ferric citrate and 0.1g of N-allyl thiourea in 30mL of deionized water to obtain solution A; while stirring magnetically at 85℃, dissolve 0.83g of cyanuric acid in 90mL of deionized water to obtain cyanuric acid solution, then slowly add solution A to the cyanuric acid solution and mix thoroughly to obtain solution B; while stirring magnetically at 85℃, dissolve 1.0g of melamine in 100mL of deionized water to obtain melamine solution, then slowly add the melamine solution to solution B and continue stirring magnetically for 4h to obtain solution C; then filter solution C to obtain supramolecular precursor.

[0064] (2) The supramolecular precursor was washed several times with deionized water and then dried at 60°C for 14 h. The dried supramolecular precursor was then placed in a tube furnace and heated to 600°C for 4 h under flowing argon at a heating rate of 5°C / min. After natural cooling, it was taken out to obtain Fe1S / CN.

[0065] (3) Add the Fe1S / CN prepared in step (2), 4.32 g of glucose, and 35 mL of ultrapure water to the inner liner of the reactor. After assembling the reactor, place it in an oven and heat it at 180°C for 10 h for filtration. Dry the filtered solid at 60°C for 14 h. Place it in a tube furnace and heat it to 900°C at a heating rate of 5°C / min under flowing argon for 4 h. After natural cooling, a highly efficient iron single-atom catalyst for degrading and defluorinating fluoroquinolone antibiotics is obtained, denoted as Fe1S / NC.

[0066] Example 3: An efficient iron single-atom catalyst (Fe1 / SNC) for the degradation and defluorination of fluoroquinolone antibiotics was prepared through the following steps:

[0067] (1) Dissolve 0.62g of ferric citrate and 0.2g of thiocyanate in 30mL of deionized water to obtain solution A; while stirring magnetically at 85℃, dissolve 0.83g of cyanuric acid in 90mL of deionized water to obtain cyanuric acid solution, then slowly add solution A to the cyanuric acid solution and mix thoroughly to obtain solution B; while stirring magnetically at 85℃, dissolve 1.0g of melamine in 100mL of deionized water to obtain melamine solution, then slowly add the melamine solution to solution B and continue stirring magnetically for 4h to obtain solution C; then filter solution C to obtain supramolecular precursor.

[0068] (2) The supramolecular precursor was washed several times with deionized water and then dried at 60°C for 14 h. The dried supramolecular precursor was then placed in a tube furnace and heated to 600°C for 4 h under flowing argon at a heating rate of 5°C / min. After natural cooling, it was taken out to obtain Fe1 / SCN.

[0069] (3) The Fe1 / SCN prepared in step (2), 0.43 g of glucose, and 35 mL of ultrapure water were added to the inner liner of the reactor. After assembling the reactor, it was placed in an oven and heated at 180 °C for 10 h for filtration. The filtered solid was dried at 60 °C for 14 h. It was then placed in a tube furnace and heated to 900 °C at a heating rate of 5 °C / min under flowing argon for 4 h. After natural cooling, a highly efficient iron single-atom catalyst for degrading and defluorinating fluoroquinolone antibiotics was obtained, denoted as Fe1 / SNC.

[0070] Figure 1 These are aberration-corrected high-angle annular dark-field scanning transmission electron microscope images and elemental distribution spectra of Fe, S, C, and N for the iron single-atom catalysts prepared in Examples 1, 2, and 3. Figure 1 (a) is a high-angle annular dark-field scanning transmission electron microscope image of the iron single-atom catalyst prepared in Example 1 with spherical aberration correction and the elemental distribution spectra of Fe, S, C, and N. Figure 1 (b) is a high-angle annular dark-field scanning transmission electron microscope image of the iron single-atom catalyst prepared in Example 2, corrected for spherical aberration, and the elemental distribution spectra of Fe, S, C, and N. Figure 1 (c) A high-angle annular dark-field scanning transmission electron microscope image and elemental distribution spectra of Fe, S, C, and N obtained by aberration correction for the iron single-atom catalyst prepared in Example 3. Figure 1 As shown in (a), the left image is a high-angle annular dark-field scanning transmission electron microscope (TEM) image of the iron single-atom catalyst prepared in Example 1 at a 5 nm scale with spherical aberration correction; the upper center image is a high-angle annular dark-field TEM image of the iron single-atom catalyst prepared in Example 1 at a 50 nm scale with spherical aberration correction; the lower center image is the original N and Fe distribution spectrum of the iron single-atom catalyst prepared in Example 1; the upper right image is the original C and Fe distribution spectrum of the iron single-atom catalyst prepared in Example 1; and the lower right image is the original S and Fe distribution spectrum of the iron single-atom catalyst prepared in Example 1. Figure 1 (a) Figure 1 (b) and Figure 1 (c) shows that the uniformly distributed single iron atoms in the iron single-atom catalysts prepared in Examples 1, 2 and 3 exist in CN; only the uniform presence of iron can be observed in the elemental distribution spectrum of Fe1 / NC; in the elemental distribution spectrum of Fe1 / SNC, Fe and S elements are not completely distributed in the same region; in the elemental distribution spectrum of Fe1S / NC, Fe and S elements are both distributed in the same region.

[0071] Figure 2The images show X-ray diffraction patterns of the iron single-atom catalysts prepared in Examples 1, 2, and 3, and NC. Figure 2 As shown, Fe1 / NC, Fe1S / NC, and Fe1 / SNC all have the same structure as NC, and no characteristic diffraction peaks of iron nanoparticles were observed, indicating that iron exists in the form of small-sized atoms in each iron single-atom catalyst, which is consistent with the test results of spherical aberration electron microscopy.

[0072] Figure 3 The images show the Fe K-edge X-ray absorption near-edge structure spectra of the iron single-atom catalysts, FeO, Fe2O3, and Fe3O4 prepared in Examples 1, 2, and 3, respectively. Figure 3 As shown, the absorption edge and transition energy of Fe1 / NC, Fe1S / NC and Fe1 / SNC are all located between the FeO and Fe2O3 references, and Fe1S / NC and Fe1 / SNC are closer to Fe3O4, confirming that the valence state of iron atoms in Fe1S / NC and Fe1 / SNC is lower than that of iron atoms in Fe1 / NC.

[0073] Figure 4 Fourier transform (FT) R-space X-ray extended edge absorption fine structure spectra of the Fe K-side of the catalysts, FeS, Fe3N, Fe4N, and iron foil (Fefoil) prepared in Examples 1, 2, and 3. Figure 4 As shown, the coordination configurations of iron atoms in Fe1 / NC, Fe1S / NC, and Fe1 / SNC were studied using extended X-ray absorption fine analysis. Simultaneously, standard samples such as FeS, Fe3N, Fe4N, and iron foil were investigated. It was found that Fe1 / NC and Fe1 / SNC... A characteristic peak clearly corresponding to Fe-N coordination scattering appears at this point, while the dominant peak of Fe1S / NC shifts to... The presence of Fe-S coordination bonds, corresponding to those in the FeS standard sample, indicates the existence of an internal Fe-S coordination configuration.

[0074] Application Example 1: Degradation of Ciprofloxacin (CIP) by Fe1 / SNC at Different PMS and PDS Concentrations

[0075] (1) Add a saturated aqueous solution of CIP to a 100 mL beaker containing 50 mL of deionized water to make the initial concentration of CIP solution 0.05 mM. Add 0.2 g / L of the iron single-atom catalyst prepared in Example 3, disperse it ultrasonically, and stir it on a magnetic stirrer until the adsorption reaction equilibrium is reached between the solid and liquid. Then add activators and control the concentrations of activators PMS and PDS to be 0.25 mM, 0.5 mM, 1.0 mM, and 2.0 mM, respectively.

[0076] (2) After adding the activator, start timing and use a syringe to take samples at 0, 10, 30, 60, 120, 180 and 240 min respectively. After solid-liquid separation using a 0.22 micrometer filter membrane, add the samples to an ampoule containing a 10% methanol solution by volume.

[0077] (3) The concentration of CIP in the solution was determined by high performance liquid chromatography.

[0078] Figure 5 The graph shows the concentration change of CIP during the degradation of CIP by different concentrations of PMS or PDS activated by the iron single-atom catalyst prepared in Example 3. Figure 5 (a) is a graph showing the concentration change of CIP during the degradation of CIP by PMS at different concentrations using the iron single-atom catalyst prepared in Example 3. Figure 5 (b) is a graph showing the concentration change of CIP during the degradation of CIP by PDS at different concentrations using the iron single-atom catalyst prepared in Example 3. According to... Figure 5 (a) and Figure 5 (b) is used to fit the first-order kinetics of each degradation curve to obtain the degradation rate diagram of Fe1 / SNC during the degradation of CIP at different PMS or PDS concentrations. Figure 6 ).like Figure 6 As shown, under low concentrations of activator (≤1.0 mM), the degradation rate of activated PDS was higher than that of activated PMS; under high concentrations of activator (>1.0 mM), the degradation rate of activated PMS was higher than that of activated PDS. The PMS consumption rate was positively correlated with its addition amount, while the relationship between the PDS consumption rate and its addition amount was not significant.

[0079] Application Example 2: Degradation of CIP by PDS Activated with Different Catalysts (Fe1 / NC, Fe1S / NC, and Fe1 / SNC)

[0080] (1) Add a saturated aqueous solution of CIP to a 100 mL beaker containing 50 mL of deionized water to make the initial concentration of CIP solution 0.05 mM. Add 0.2 g / L of the iron single-atom catalyst (Fe1 / NC) prepared in Example 1, the iron single-atom catalyst (Fe1S / NC) prepared in Example 2, the iron single-atom catalyst (Fe1 / SNC) prepared in Example 3, NC or SNC respectively, and disperse them by ultrasonication. Stir on a magnetic stirrer until the adsorption reaction equilibrium is reached between the solid and liquid. Then add an activator and control the concentration of the activator PDS to 2.0 mM.

[0081] (2) After adding the activator, start timing and use a syringe to take samples at 0, 10, 30, 60, 120, 180 and 240 min respectively. After solid-liquid separation using a 0.22 micrometer filter membrane, add the samples to an ampoule containing a 10% methanol solution by volume and to a centrifuge tube.

[0082] (3) The concentrations of CIP and fluoride ions in the solution were determined by high performance liquid chromatography and fluoride ion electrode, respectively.

[0083] Figure 7 The graph shows the change of CIP concentration over time during the PDS activation process of Fe1 / NC, Fe1S / NC, Fe1 / SNC, NC and SNC or the CIP degradation process of PDS alone. Figure 8 The graph shows the change in defluorination rate over time during the PDS activation process or the PDS degradation of CIP by PDS alone, using Fe1 / NC, Fe1S / NC, Fe1 / SNC, NC, and SNC. Figure 9 The graph shows the degradation rate and final defluorination rate of PDS during the degradation of CIP by Fe1 / NC, Fe1S / NC, Fe1 / SNC, NC and SNC activated PDS.

[0084] Figure 7 , Figure 9 The results showed that Fe1 / SNC activated PDS degraded CIP at a significantly faster rate than Fe1S / NC and Fe1 / NC. Figure 8 The results showed that the defluorination rate of PDS activated by Fe1 / SNC to CIP was also greater than that of Fe1S / NC and Fe1 / NC, and there was a positive correlation between the reaction rate constant and the defluorination rate.

[0085] Application Example 3: Degradation of CIP by PMS activated with different catalysts (Fe1 / NC, Fe1S / NC, and Fe1 / SNC)

[0086] (1) Add a saturated aqueous solution of CIP to a 100 mL beaker containing 50 mL of deionized water to make the initial concentration of CIP solution 0.05 mM. Add 0.2 g / L of the iron single-atom catalyst (Fe1 / NC) prepared in Example 1, the iron single-atom catalyst (Fe1S / NC) prepared in Example 2, the iron single-atom catalyst (Fe1 / SNC) prepared in Example 3, NC or SNC respectively, and disperse them by ultrasonication. Stir on a magnetic stirrer until the adsorption reaction equilibrium is reached between the solid and liquid. Then add an activator and control the concentration of the activator PMS to be 2.0 mM.

[0087] (2) After adding the activator, start timing and use a syringe to take samples at 0, 10, 30, 60, 120, 180 and 240 min respectively. After solid-liquid separation using a 0.22 micrometer filter membrane, add the samples to an ampoule containing a 10% methanol solution by volume and to a centrifuge tube.

[0088] (3) The concentrations of CIP and fluoride ions in the solution were determined by high performance liquid chromatography and fluoride ion electrode, respectively.

[0089] Figure 10 The graph shows the degradation rate and final defluorination rate of CIP during the PMS degradation process activated by Fe1 / NC, Fe1S / NC, Fe1 / SNC, NC and SNC. Figure 10 The results showed that the degradation rate and defluorination rate of CIP by Fe1 / SNC activated PMS were not significantly different from those of Fe1S / NC and Fe1 / NC, and the relationship between the reaction rate constant and the defluorination rate was not obvious.

[0090] Application Example 4 investigates the contribution rate of various bioactive species to CIP degradation.

[0091] (1) Add a saturated aqueous solution of CIP to several 100 mL beakers containing 50 mL of deionized water, so that the initial concentration of the CIP solution is 0.05 mM. Weigh out various quenchers and add them to each CIP solution, so that the concentrations of methanol and tert-butanol are 500 mM, the concentration of nitroblue tetrazolium is 5 mM, the concentration of methyl phenyl sulfoxide is 5 mM, and the concentration of sodium azide is 5 mM. Add 0.2 g / L of the iron single-atom catalyst (Fe1 / NC) prepared in Example 1, the iron single-atom catalyst (Fe1S / NC) prepared in Example 2, the iron single-atom catalyst (Fe1 / SNC) prepared in Example 3, NC or SNC to each beaker, and disperse them by ultrasonication. Stir on a magnetic stirrer until the adsorption reaction equilibrium is reached between the solid and liquid. Then add an activator and control the concentration of the activator PDS to be 2.0 mM.

[0092] (2) After adding the activator, start timing and use a syringe to take samples at 0, 10, 30, 60, 120, 180 and 240 min respectively. After solid-liquid separation using a 0.22 micrometer filter membrane, add the samples into an ampoule containing a 10% methanol solution by volume.

[0093] (3) The concentration of CIP in the solution was determined by high performance liquid chromatography.

[0094] Figure 11 Fe1 / NC, Fe1S / NC, Fe1 / SNC, NC, and SNC activate PMS to degrade various reactive species (free radicals such as ·OH, ·SO4) generated during CIP degradation. - O2 - (etc.), singlet oxygen ( 1 O2) and high-priced iron (Fe) VI =O)) contributes to CIP degradation. Based on the addition of methanol (quenching ·OH and ·SO4) - ), tert-butanol (quenched by ·OH), nitroblue tetrazol (quenched by ·O2) - Sodium azide (quenching) 1 O2) and methyl phenyl sulfoxide (quenching Fe) VI =O) The degradation rate of CIP under different single-atom catalysts, and the contribution rate of various active species to CIP degradation, such as Figure 11 As shown, Fe1 / SNC activated PMS generates 1 O2 is the primary active component, while Fe1 / SNC-activated PDS primarily generates electron transfer (ET). The formation mechanism involves the binding of Fe atoms within the Fe1 / SNC to the terminal O sites within the PMS molecule, resulting in the breaking of the O-O bond and subsequent self-disproportionation reaction to generate the PDS. 1 O2; while Fe atoms in Fe1 / SNC form an internal complex (PDS*) with PDS molecules, using the carrier NC as a platform for electron transfer. Fe1 / SNC extracts electrons from antibiotic molecules, and this activation process is mainly ET.

[0095] Application Example 5: Degradation and Defluorination Effects of Fluoroquinolone Antibiotics

[0096] (1) Saturated aqueous solutions of norfloxacin (NOX), moxifloxacin (MOX), pazufloxacin (PAZ), and gatifloxacin (GAT) were added to several 100 mL beakers containing 50 mL of deionized water, respectively, so that the initial concentration of each antibiotic solution was 0.05 mM. 0.2 g / L of the iron single-atom catalyst (Fe1 / NC) prepared in Example 1, the iron single-atom catalyst (Fe1S / NC) prepared in Example 2, or the iron single-atom catalyst (Fe1 / SNC) prepared in Example 3, or NC, were added and ultrasonically dispersed. The mixture was then stirred on a magnetic stirrer until the adsorption reaction equilibrium was reached between the solid and liquid phases. An activator was then added, and the concentration of the activator PDS was controlled to be 1.0 mM.

[0097] (2) After adding the activator, start timing and use a syringe to take samples at 0, 10, 30, 60, 120, 180 and 240 min respectively. After solid-liquid separation using a 0.22 micrometer filter membrane, add the samples to an ampoule containing a 10% methanol solution by volume and to a centrifuge tube.

[0098] (3) The concentrations of NOX, MOX, PAZ and GAT and the concentration of fluoride ions in the solution were determined by high performance liquid chromatography and fluoride ion electrode, respectively.

[0099] Figure 12 The graph shows the changes in NOx concentration and defluorination rate over time during NOx degradation by Fe1 / NC, Fe1S / NC, Fe1 / SNC, and NC-activated PDS. Figure 12 (a) is a graph showing the change of NOx concentration over time during the NOx degradation process of PDS activated by Fe1 / NC, Fe1S / NC, Fe1 / SNC, and NC. Figure 12 (b) is a graph showing the change of defluorination rate over time during the NOx degradation process of PDS activated by Fe1 / NC, Fe1S / NC, Fe1 / SNC and NC. Figure 13 The graph shows the changes in MOX concentration and defluorination rate over time during the MOX degradation process using Fe1 / NC, Fe1S / NC, Fe1 / SNC, and NC-activated PDS. Figure 13 (a) is a graph showing the change of MOX concentration over time during the MOX degradation process of PDS activated by Fe1 / NC, Fe1S / NC, Fe1 / SNC, and NC. Figure 13 (b) is a graph showing the change of defluorination rate over time during the degradation of MOX by PDS activated by Fe1 / NC, Fe1S / NC, Fe1 / SNC and NC. Figure 14 The graph shows the changes in PAZ concentration and defluorination rate over time during the PAZ degradation process of Fe1 / NC, Fe1S / NC, Fe1 / SNC, and NC activated PDS. Figure 14 (a) is a graph showing the change of PAZ concentration over time during the PAZ degradation process of PDS activated by Fe1 / NC, Fe1S / NC, Fe1 / SNC, and NC. Figure 14 (b) is a graph showing the change of defluorination rate over time during the PAZ degradation process of Fe1 / NC, Fe1S / NC, Fe1 / SNC and NC activated PDS. Figure 15 The graph shows the changes in GAT concentration and defluorination rate over time during the GAT degradation process using Fe1 / NC, Fe1S / NC, Fe1 / SNC, and NC-activated PDS. Figure 15 (a) is a graph showing the change of GAT concentration over time during the degradation of GAT by Fe1 / NC, Fe1S / NC, Fe1 / SNC, and NC-activated PDS. Figure 15 (b) is a graph showing the change of defluorination rate over time during the degradation of GAT by PDS activated by Fe1 / NC, Fe1S / NC, Fe1 / SNC and NC.

[0100] Figure 12 , Figure 13 , Figure 14 and Figure 15 The results show that Fe1 / SNC, Fe1S / NC, and Fe1 / NC activated PDS can completely degrade MOX, PAZ, and GAT within 1 hour, and completely degrade NOX within 2 hours, with a defluorination rate of 10%-30%.

[0101] Figure 16 Degradation rate diagrams for fluoroquinolone antibiotics during the degradation process of PDS activated by Fe1 / NC, Fe1S / NC, Fe1 / SNC, and NC. Figure 17 Dechlorination rate diagrams for the degradation of fluoroquinolone antibiotics by PDS activated by Fe1 / NC, Fe1S / NC, Fe1 / SNC, and NC.

[0102] Figure 16 and Figure 17 Different catalysts exhibit varying degradation effects and defluorination rates for fluoroquinolone antibiotics, possibly due to the different effects of ET on the valence groups (-F, piperazine ring, cyclopropyl, hydroxyl, etc.) of fluoroquinolone antibiotics. For example, Fe1S / NC showed the best effect on NOx degradation, while Fe1 / SNC showed the best effect on MOX and PAZ degradation, and the best effect on CIP defluorination.

[0103] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A highly efficient iron single-atom catalyst for degrading and defluorinating fluoroquinolone antibiotics, characterized in that, The highly efficient iron single-atom catalyst for degrading and defluorinating fluoroquinolone antibiotics was prepared by the following steps: (1) Dissolve 0.05~0.1 g of ferric citrate and 0.07~0.13 g of N-allyl thiourea in 30~40 mL of deionized water to obtain solution A; while stirring magnetically at 85~90℃, dissolve 0.8~0.9 g of cyanuric acid in 90~100 mL of deionized water to obtain cyanuric acid solution, and then slowly add solution A to the cyanuric acid solution and mix thoroughly to obtain solution B; while stirring magnetically at 85~90℃, dissolve 0.9~1.0 g of melamine in 100~110 mL of deionized water to obtain melamine solution, and then slowly add the melamine solution to solution B and continue stirring magnetically for 4~5 h to obtain solution C; Solution C was then filtered to obtain the supramolecular precursor; (2) The supramolecular precursor was washed several times with deionized water and then dried at 55-65℃ for 12-16 h. The dried supramolecular precursor was then placed in a tube furnace and heated to 550-650℃ for 4-5 h under flowing argon at a heating rate of 4-6℃ / min. After natural cooling, it was taken out to obtain Fe1S / CN. (3) Add the Fe1S / CN prepared in step (2), 4.3~4.4 g of glucose and 30~40 mL of ultrapure water into the inner liner of the reactor. After assembling the reactor, place it in an oven and heat it at 170~190℃ for 10~11 h. Then filter it. Dry the filtered solid at 55~65℃ for 12~16 h. Place it in a tube furnace and heat it to 800~1000℃ at a heating rate of 4~6℃ / min under flowing argon for 4~5 h. After natural cooling, obtain an iron single-atom catalyst that degrades and defluorinates fluoroquinolone antibiotics, denoted as Fe1S / NC. The fluoroquinolone antibiotics mentioned are ciprofloxacin, norfloxacin, moxifloxacin, pazufloxacin, or gatifloxacin.

2. A highly efficient iron single-atom catalyst for degrading and defluorinating fluoroquinolone antibiotics, characterized in that, The highly efficient iron single-atom catalyst for degrading and defluorinating fluoroquinolone antibiotics was prepared by the following steps: (1) Dissolve 0.6~0.7 g of ferric citrate and 0.15~0.25 g of thiocyanate in 30~40 mL of deionized water to obtain solution A; while stirring magnetically at 85~90℃, dissolve 0.8~0.9 g of cyanuric acid in 90~100 mL of deionized water to obtain cyanuric acid solution, then slowly add solution A to the cyanuric acid solution and mix thoroughly to obtain solution B; while stirring magnetically at 85~90℃, dissolve 0.9~1.0 g of melamine in 100~110 mL of deionized water to obtain melamine solution, then slowly add the melamine solution to solution B and continue stirring magnetically for 4~5 h to obtain solution C; Solution C was then filtered to obtain the supramolecular precursor; (2) The supramolecular precursor was washed several times with deionized water and then dried at 55-65℃ for 12-16 h. The dried supramolecular precursor was then placed in a tube furnace and heated to 550-650℃ for 4-5 h under flowing argon at a heating rate of 4-6℃ / min. After natural cooling, it was taken out to obtain Fe1 / SCN. (3) Add the Fe1 / SCN prepared in step (2), 4.3~4.4 g of glucose and 30~40 mL of ultrapure water into the inner liner of the reactor. After assembling the reactor, place it in an oven and heat it at 170~190℃ for 10~11 h. Then filter it. Dry the filtered solid at 55~65℃ for 12~16 h. Place it in a tube furnace and heat it to 800~1000℃ at a heating rate of 4~6℃ / min under flowing argon for 4~5 h. After natural cooling, obtain an iron single-atom catalyst that degrades and defluorinates fluoroquinolone antibiotics, denoted as Fe1 / SNC. The fluoroquinolone antibiotics mentioned are ciprofloxacin, norfloxacin, moxifloxacin, pazufloxacin, or gatifloxacin.

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