Organic manganese salt doped ZIS photocatalytic material as well as preparation method and application thereof

Abstract

The invention relates to the field of photocatalytic materials, and discloses an organic manganese salt doped ZIS photocatalytic material and a preparation method and application thereof.The preparation method comprises the following steps that ZnCl2, InCl3. 4H2O and C2H5NS are dissolved in deionized water, then organic manganese salt is added, magnetic stirring is conducted to enable the organic manganese salt to be completely dissolved, then a reaction is conducted for 10-20 h at the temperature of 50-120 DEG C, and cleaning and drying are conducted to obtain the organic manganese salt doped ZIS photocatalytic material. The organic manganese salt doped ZIS photocatalytic material is obtained. The organic manganese salt doped ZIS photocatalytic material prepared by the preparation method disclosed by the invention has the advantages that the degradation performance and the sterilization performance on organic matters are greatly improved.

Description

Technical Field

[0001] The present invention relates to the field of photocatalytic materials, and in particular to an organic manganese salt-doped ZIS photocatalytic material and a preparation method and application thereof. Background Art

[0002] The prevention and control of marine biofouling is a global, unresolved challenge. It not only causes enormous economic losses but also poses significant environmental and ecological risks. Therefore, research on marine biofouling prevention and control has important practical implications. Currently, the addition of toxic copper-based biocides to coatings remains the primary antifouling method. However, the continued release of toxic substances can threaten the growth and development of non-target organisms in the marine environment. Consequently, marine-friendly photocatalytic antifouling strategies are gaining increasing attention.

[0003] Photocatalytic materials can generate strong oxidizing free radicals (ROS) under light, which can effectively kill microorganisms. Therefore, there is a certain application potential in sterilizing and degrading organic matter for anti-fouling through green and environmentally friendly photocatalytic technology. ZnIn2S4 (ZIS) photocatalytic materials have a strong visible light response, but pure ZIS photocatalytic materials have the problem of high recombination rate of photogenerated carriers, which limits the high catalytic activity of ZIS. Element doping can adjust the electronic structure of photocatalytic materials, form impurity energy levels or defects, and improve the separation rate of photogenerated carriers. Element doping is widely used to improve the photocatalytic performance of ZIS. However, inorganic manganese doping currently has disadvantages such as unstable doping effect and uneven doping. Summary of the Invention

[0004] To solve the above technical problems, the present invention provides an organic manganese salt-doped ZIS photocatalytic material and its preparation method and application, so as to achieve the purpose of improving the degradation performance and bactericidal performance of organic matter.

[0005] To achieve the above object, the technical solution of the present invention is as follows:

[0006] A method for preparing a photocatalytic material of organic manganese salt-doped ZIS comprises the following steps:

[0007] ZnCl2, InCl3·4H2O and C2H5NS were dissolved in deionized water, and then organic manganese salt was added and magnetically stirred to completely dissolve the mixture. The mixture was then reacted at 50-120°C for 10-20h, washed and dried to obtain an organic manganese salt-doped ZIS photocatalytic material.

[0008] In the above scheme, the organic manganese salt is Mn(CH3COO)2 or Mn(C6H 11 O7)2.

[0009] In the above scheme, the molar ratio of ZnCl2, InCl3·4H2O, C2H5NS and organic manganese salt is 1:2:4:0.5~5.

[0010] In the above protocol, magnetic stirring was performed for 30 min.

[0011] In the above scheme, after complete dissolution, the reaction was carried out at 100° C. for 12 h, and after multiple washings with anhydrous ethanol and deionized water, the reaction was dried at 60° C. for 12 h to obtain the organic manganese salt-doped ZIS photocatalytic material.

[0012] A photocatalytic material of ZIS doped with an organic manganese salt prepared by the preparation method described above.

[0013] An application of the above-mentioned organomanganese salt-doped ZIS photocatalytic material in degrading organic matter in water and killing bacteria.

[0014] In a further technical solution, the organic matter refers to methyl orange, rhodamine and antibiotics.

[0015] In a further technical solution, the bacteria refer to Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus.

[0016] Through the above technical solution, the present invention provides an organic manganese salt-doped ZIS photocatalytic material and its preparation method and application, which have the following beneficial effects:

[0017] 1. The degradation effect of the organic manganese salt-doped ZIS photocatalytic material prepared by the present invention on methyl orange (MO) is significantly improved compared with the degradation effect of the photocatalytic materials of ZIS and inorganic manganese salt-doped ZIS;

[0018] 2. The sterilization rates of the organic manganese salt-doped ZIS photocatalytic material prepared by the present invention against Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus were increased by 8.11%, 14.04% and 28.16% respectively compared with pure ZIS;

[0019] 3. The organomanganese salt-doped ZIS photocatalytic material prepared by the present invention has stable cyclic bactericidal performance;

[0020] 4. The organomanganese salt-doped ZIS photocatalytic material prepared by the present invention has improved mobility of photogenerated electrons and carrier separation efficiency; thereby improving the photocatalytic sterilization and degradation functions of ZIS.

[0021] In summary, the present invention compares the different effects of doping ZIS with organic and inorganic manganese salts, providing more insights for the subsequent regulation of doping behavior and the selection of doping sources by organic small molecules. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for describing the embodiments or the prior art.

[0023] Figure 1 The degradation performance of MO by the photocatalytic materials prepared in the present invention is shown in FIG. (a) is a comparison of the degradation performance of Example 1 and Comparative Example 1, and (b) is a comparison of the degradation performance of ZM-3 in Example 1 and Comparative Examples 1 and 2.

[0024] Figure 2 The photocatalytic sterilization performance of the photocatalytic material prepared by the present invention on P. aeruginosa; (a) is a comparison of the photocatalytic sterilization performance of Example 1 and Comparative Example 1 on P. aeruginosa, and (b) is the cyclic sterilization stability of sample ZM-3 on P. aeruginosa;

[0025] Figure 3 The photocatalytic sterilization performance of ZIS, ZM-3 and blank group samples prepared by the present invention on E. coli;

[0026] Figure 4 The photocatalytic sterilization performance of ZIS, ZM-3 and blank group samples prepared by the present invention on S. aureus;

[0027] Figure 5 The XRD patterns of the photocatalytic materials prepared in the present invention are as follows: (a) is the XRD pattern of Example 1 and Comparative Example 1; (b) is the XRD pattern of ZM-3 in Example 1 and Comparative Examples 1 and 2;

[0028] Figure 6 These are SEM images of the photocatalytic materials prepared in the present invention; (a) is ZIS; (b) is ZM-3; (c) is ZIS-Mn(NO3)2; (d) is ZIS-MnCl2; and (e) is ZIS-MnSO4. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present invention.

[0030] The present invention provides a photocatalytic material of organic manganese salt doped ZIS and its preparation method and application. Specific embodiments are as follows:

[0031] Example 1

[0032] 0.4090 g of ZnCl₂, 1.7594 g of InCl₃·4H₂O, and 0.9016 g of C₂H₅NS were dissolved in 90 mL of deionized water. Once completely dissolved, the mixture was divided into three equal portions, and then 0.0847 g, 0.1411 g, 0.4233 g, and 0.8466 g of Mn(CH₃COO)₂ were added, respectively. The mixture was stirred with a magnetic stirrer for 30 minutes to allow complete dissolution, and then reacted at 100°C for 12 hours. After the reaction, the products were collected, washed multiple times with deionized water and anhydrous ethanol, and dried at 60°C for 12 hours. The resulting products were labeled ZM-1, ZM-2, ZM-3, and ZM-4, respectively.

[0033] Comparative Example 1

[0034] Accurately weigh 0.1363 g of ZnCl₂, 0.5865 g of InCl₃·4H₂O, and 0.3005 g of C₂H₅NS in 30 mL of deionized water. The mixture was stirred with a magnetic stirrer for 30 minutes to completely dissolve. The mixture was then transferred to an autoclave and reacted at 100°C for 12 hours. After the reaction, the product was collected, washed multiple times with deionized water and anhydrous ethanol, and dried at 60°C for 12 hours. The resulting material is ZIS.

[0035] Comparative Example 2

[0036] 0.4090 g ZnCl2, 1.7594 g InCl3·4H2O, and 0.9016 g C2H5NS were dissolved in 90 mL of deionized water. Once completely dissolved, the mixture was divided into three equal portions. 0.3079 g MnCl2, 0.2687 g MnSO4, and 0.3897 g Mn(NO3)2·4H2O were then added. The mixture was stirred with a magnetic stirrer for 30 minutes to allow complete dissolution, and then reacted at 100°C for 12 hours. After the reaction, the products were collected, washed multiple times with deionized water and anhydrous ethanol, and dried at 60°C for 12 hours. The resulting products were labeled ZIS-MnCl2, ZIS-MnSO4, and ZIS-Mn(NO3)2, respectively.

[0037] Degradation and sterilization performance test

[0038] 1. Photocatalytic material degradation performance test on organic matter methyl orange (MO):

[0039] The MO degradation experiment was carried out in a photoreactor, using an 800W xenon lamp as the light source and a 425nm filter to filter the ultraviolet light (light intensity of 80mW·cm -2 ).

[0040] First, accurately weigh 10 mg of the photocatalytic material prepared in the above examples and comparative examples, then add it to a quartz tube containing 50 mL of 10 ppm MO solution, transfer the quartz tube to a photoreactor, and then stir it in the dark for 1 hour, sampling every 30 minutes to ensure that the dark adsorption reaches equilibrium. After the adsorption is completed, turn on the light source, and also sample and filter the photocatalytic material every 30 minutes. After the photocatalytic degradation experiment is completed, use an enzyme marker to measure the absorbance of the solution at 465 nm and calculate the degradation rate. The results are shown in Figure 1 , where the horizontal axis represents the dark state and light exposure time, and the vertical axis represents the MO concentration C at different times t The ratio of the initial concentration C0.

[0041] from Figure 1 As can be seen in (a), organic Mn salt doping enhances the dark-state adsorption capacity of ZIS for MO, which is related to the small morphology and increased specific surface area after doping. After 120 minutes of simulated visible light irradiation, the degradation rates of MO for ZIS, ZM-1, ZM-2, and ZM-3 samples were 55.73%, 78.24%, 81.09%, and 84.35%, respectively. Sample ZM-3 exhibited the highest MO degradation rate, 1.53 times that of ZIS. Furthermore, the photocatalytic degradation performance gradually improved with increasing Mn content. However, sample ZM-4 no longer exhibited degradation performance after the addition of excessive Mn(CH3COO)2, indicating that excessive Mn can affect the structure of ZIS, thereby limiting its photocatalytic activity.

[0042] Figure 1 (b) shows ZIS doped with different Mn sources. It can be seen from the figure that the degradation rates of ZIS, ZM-3, ZIS-Mn(NO3)2, ZIS-MnCl2 and ZIS-MnSO4 under visible light irradiation for 150 minutes are 48.59%, 68.10%, 52.91%, 38.27% and 31.51%, respectively. The degradation rate of MO is the highest after Mn(CH3COO)2 is doped as a manganese source in ZIS. Therefore, Mn(CH3COO)2 as a Mn source can improve the photocatalytic performance of ZIS better than Mn(NO3)2, MnCl2 and MnSO4.

[0043] 2. Bactericidal performance of photocatalytic materials against Pseudomonas aeruginosa (P.aeruginosa)

[0044] The bactericidal experiment was carried out in a photoreactor, in which an 800W xenon lamp was used as the simulated light source, and a 425nm filter was used to filter the ultraviolet light. The light intensity was 80mW·cm- 2 .

[0045] First, a single colony of P. aeruginosa was inoculated into LB liquid medium and incubated at 37°C for 12 hours to obtain an activated bacterial suspension. The cells were then washed with sterile 0.1 M phosphate buffered saline (PBS) to remove any residual LB medium, then resuspended and diluted with PBS. The final concentration of the P. aeruginosa inoculum was 3.31 × 10 7 CFU / mL. 0.5mL of P.aeruginosa inoculum was added to a quartz tube containing 50mL of 0.1M PBS solution, and 10mg of the photocatalytic material prepared in the above examples and comparative examples was added to each quartz tube. No photocatalytic material was added to the blank group. The quartz tube was adsorbed in the dark for 1 hour to reach adsorption equilibrium. After turning on the light source, samples were taken every 2 hours, and the total illumination time was 6 hours. The number of bacteria in the taken bacterial samples was counted using the colony counting method, and the antibacterial rate was then calculated. The results are shown in Figure 2 , where the horizontal axis is the dark state and light exposure time, and the vertical axis is the bacterial survival rate.

[0046] Figure 2 (a) is the curve of the survival rate of P. aeruginosa changing with the illumination time. It can be seen from the figure that the bacterial survival rate of different materials changes little after 1 hour of dark adsorption, indicating that the adsorption of the materials to P. aeruginosa is negligible. When the illumination is 6 hours, the survival rates of samples ZIS, ZM-1, ZM-2, ZM-3 and ZM-4 are 15.87%, 12.23%, 12.19%, 7.76% and 42.63% respectively. Compared with ZIS, Mn doping improves its bactericidal performance against P. aeruginosa. Among them, the bactericidal performance of ZM-3 sample is the best, which is 92.24%, which is 1.10 times the bactericidal rate of ZIS (84.13%). Therefore, Mn doping can effectively improve the photocatalytic bactericidal performance of ZIS. However, after adding excessive Mn (CH3COO) 2, the bactericidal performance of sample ZM-4 is the worst. Five cyclic sterilization experiments were carried out in this study. From Figure 2 In (b), it can be seen that the cyclic sterilization rates of the samples are 92.24%, 86.89%, 93.65%, 89.32% and 87.52%, respectively, indicating that the cyclic sterilization rates of the samples have not changed significantly.

[0047] 3. Bactericidal performance of photocatalytic materials against Escherichia coli (E. coli)

[0048] First, a single E. coli colony was inoculated into LB liquid medium and incubated at 37°C for 12 hours to obtain an activated bacterial suspension. Simultaneously, the bacteria were washed with sterile 0.1M phosphate buffered saline (PBS) to remove residual LB medium, then resuspended and diluted with PBS. The final concentration of the E. coli inoculum was 2.86×107 CFU / mL. 0.5mL of E. coli inoculum was added to a quartz tube containing 50mL of 0.1M PBS solution, and 10mg of the photocatalytic material prepared in the above examples and comparative examples was added to each quartz tube. No photocatalytic material was added to the blank group. The quartz tube was adsorbed in the dark for 1 hour to reach adsorption equilibrium. Samples were taken 5 hours after the light source was turned on. The number of bacteria in the taken bacterial samples was counted using the colony counting method, and the antibacterial rate was then calculated. The results are shown in Figure 3 , where the horizontal axis is the dark state and light exposure time, and the vertical axis is the bacterial survival rate.

[0049] Figure 3 The graph shows how E. coli survival rates in the ZIS, ZM-3, and blank groups changed with illumination time. The ZM-3 treatment group demonstrated a faster kill rate. After 5 hours of illumination, the ZM-3 kill rate reached 99.24%, a 14.04% increase compared to the ZIS treatment group (85.20%). This demonstrates that Mn(CH3COO)2 doping can enhance the sterilization of ZIS against Gram-negative bacteria.

[0050] 4. Bactericidal performance of photocatalytic materials against Staphylococcus aureus (S. aureus)

[0051] First, prepare a S. aureus inoculum. Pick a single S. aureus colony and inoculate it into LB liquid medium. Incubate at 37°C for 12 hours to obtain an activated bacterial suspension. Wash the bacteria with sterile 0.1M phosphate buffered saline (PBS) to remove residual LB medium. Then resuspend and dilute with PBS. The final concentration of the S. aureus inoculum is 2.57×10 7 CFU / mL. 0.5mL of S. aureus inoculum was added to a quartz tube containing 50mL of 0.1M PBS solution, and 10mg of the photocatalytic material prepared in the above examples and comparative examples was added to each quartz tube. No photocatalytic material was added to the blank group. The quartz tube was adsorbed in the dark for 1 hour to reach adsorption equilibrium. Samples were taken after turning on the light source for 6 hours. The number of bacteria in the taken bacterial samples was counted using the colony counting method, and the antibacterial rate was then calculated. The results are shown in Figure 4 , where the horizontal axis is the dark state and light exposure time, and the vertical axis is the bacterial survival rate.

[0052] Figure 4 Figure 2 shows the bactericidal performance of ZIS, ZM-3, and a blank control group against S. aureus. Similarly, after 6 hours of illumination, ZM-3 exhibited significantly higher bactericidal efficacy than ZIS. ZM-3 achieved a bactericidal rate of 97.21%, a 28.16% increase over the ZIS-treated group (69.05%). This demonstrates that Mn(CH3COO)2 doping enhances the bactericidal activity of ZIS against Gram-positive bacteria.

[0053] Performance Characterization

[0054] 1. XRD pattern

[0055] The XRD pattern of the photocatalytic material prepared by the present invention is shown in Figure 5 .from Figure 5 In (a), we can see that ZIS was successfully prepared, and the prepared ZIS belongs to the hexagonal crystal system (PDF-65-2023), and the material peak is relatively sharp, indicating that it has a high degree of crystallinity. Among them, the diffraction angles with more obvious peaks of 21.59°, 27.69°, 47.18° and 52.38° correspond to the (006), (102), (110) and (116) crystal planes of ZIS respectively. Figure 5 In (b), it can be seen that the effect of different manganese source doping on the ZIS crystal structure is small, and the crystal structure of ZIS is still maintained after doping with different manganese sources.

[0056] 2. SEM images

[0057] The SEM image of the photocatalytic material prepared by the present invention is shown in FIG. Figure 6 SEM images show that the ZIS, ZM-3, ZIS-Mn(NO3)2, ZIS-MnCl2, and ZIS-MnSO4 samples all exhibit a clustered structure composed of hierarchical nanosheets, but the ZM-3 flake structure is smaller and more dispersed. This increases the surface area of ​​the ZIS, exposing more active sites and facilitating the photocatalytic reaction.

[0058] 3. Specific surface area

[0059] Table 1 lists the specific surface areas of samples doped with different manganese sources. It can be seen from the table that the specific surface areas of ZIS, ZM-3, ZIS-Mn(NO3)2, ZIS-MnCl2 and ZIS-MnSO4 are 89.83, 137.84, 101.47, 69.04 and 23.52 m 2 / g, Mn(CH3COO)2 doping increased the values ​​of ZIS, Mn(NO3)2, MnCl2 and MnSO4 by 48.01, 36.37, 68.70 and 114.32 m 2 / g, and the increase in specific surface area also reflects the advantage of Mn(CH3COO)2 doping.

[0060] Table 1 Specific surface area of ​​different materials

[0061] sample ZIS ZM-3 <![CDATA[ZIS-Mn(NO3)2]]> <![CDATA[ZIS-MnCl2]]> <![CDATA[ZIS-MnSO4]]> <![CDATA[Specific surface area (m 2 / g)]]> 89.83 137.84 101.47 69.04 23.52

[0062] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing a photocatalytic material of organic manganese salt doped ZIS, characterized in that: The process includes the following: ZnCl2, InCl3·4H2O and C2H5NS were dissolved in deionized water, and then organic manganese salt was added and magnetically stirred to completely dissolve the mixture. The mixture was then reacted at 50-120°C for 10-20h, washed and dried to obtain an organic manganese salt-doped ZIS photocatalytic material.

2. The method for preparing a photocatalytic material of an organic manganese salt-doped ZIS according to claim 1, characterized in that: The organic manganese salt is Mn(CH3COO)2 or Mn(C6H 11 O7)2.

3. The method for preparing a photocatalytic material of an organic manganese salt-doped ZIS according to claim 1, characterized in that: The molar ratio of ZnCl2, InCl3·4H2O, C2H5NS and organic manganese salt is 1:2:4:0.5~5.

4. The method for preparing a photocatalytic material of an organic manganese salt-doped ZIS according to claim 1, characterized in that: Magnetic stirring for 30 min.

5. The method for preparing a photocatalytic material of organic manganese salt-doped ZIS according to claim 1, characterized in that: After complete dissolution, the reaction was carried out at 100°C for 12 hours, and after multiple washings with anhydrous ethanol and deionized water, the reaction was dried at 60°C for 12 hours to obtain an organic manganese salt-doped ZIS photocatalytic material.

6. A photocatalytic material of ZIS doped with an organic manganese salt prepared by the preparation method according to claim 1.

7. Use of the organomanganese salt-doped ZIS photocatalytic material as claimed in claim 6 in degrading organic matter in water and killing bacteria.

8. The use according to claim 7, characterized in that The organic substances refer to methyl orange, rhodamine and antibiotics.

9. The use according to claim 7, characterized in that The bacteria referred to are Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus.

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