A novel Zn-based photosynthetic hydrogen peroxide 3-x Cu x In2S 6-y O y catalyst

Abstract

This invention relates to the field of photocatalysis technology and provides a novel Zn-based method for the photosynthesis of hydrogen peroxide. 3‑x Cu x In2S 6‑y O y The catalyst is prepared by the following steps: dissolving ZnSO4·7H2O and InCl3·4H2O in deionized water, stirring, adding CuCl2, continuing stirring, and finally adding thioacetamide. After stirring, the mixture is transferred to a polytetrafluoroethylene-lined stainless steel reactor for reaction, cooled to room temperature, centrifuged to collect the precipitate, washed several times, and dried to obtain Zn. 3‑x Cu x In2S6 (ZCIS) is then heat-treated in air to obtain Zn. 3‑x Cu x In2S 6‑y O y (ZCISO). This invention synthesizes Zn. 3‑x Cu x In2S 6‑y O y The catalyst can be applied to the field of photocatalytic hydrogen peroxide production and to sterilize and degrade dye pollutants.

Description

Technical Field

[0001] This invention belongs to the field of photocatalysis technology, and particularly relates to a novel Zn-based method for the photosynthesis of hydrogen peroxide. 3-x Cu x In2S 6- y O y catalyst. Background Technology

[0002] Two-dimensional semiconductor sulfides, with their suitable optical band gaps, tunable functionality, simple preparation, excellent catalytic activity, and mass production capabilities, have become ideal substrate materials for sustainable development fields such as gas / liquid separation, optoelectronic devices, and catalysis. Among them, two-dimensional sulfides are favored by researchers due to their superior stability and non-toxicity. Furthermore, their suitable band positions allow for applications in H2O oxidation, H2 production, CO2 reduction, and H2O2 synthesis. However, conventional modification strategies cannot satisfy the requirement of preserving the structure and activity of two-dimensional sulfides without introducing new electron-hole recombination centers, thus posing a challenge to achieving high activity, uniform morphology, and easy preparation. Structural defects depend on specific reaction conditions and chemical reagents, easily leading to new electron-hole recombination centers. Constructing heterojunctions causes additional structural changes in the material. Loading single atoms is both costly and results in small sample quantities per synthesis.

[0003] Despite the numerous modification strategies for two-dimensional sulfides, they cannot fundamentally solve the problems of rapid electron-hole recombination between layers and low surface activity. Summary of the Invention

[0004] The purpose of this invention is to provide a novel Zn-based photosynthetic hydrogen peroxide. 3-x Cu x In2S 6-y O y The catalyst is designed to address the problems raised in the background section above.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] On the one hand, the present invention provides a novel Zn for the photosynthesis of hydrogen peroxide. 3-x Cu x In2S 6-y O y The method for preparing the catalyst includes the following steps:

[0007] Dissolve ZnSO4·7H2O and InCl3·4H2O in deionized water, stir, add CuCl2, continue stirring, and finally add thioacetamide. After stirring, transfer the mixture to a polytetrafluoroethylene-lined stainless steel reactor for reaction.

[0008] After the reaction was complete, the mixture was cooled to room temperature, centrifuged to collect the precipitate, washed several times, and dried to obtain Zn. 3-x Cu x In2S6, named ZCIS, is then heat-treated in air to obtain Zn. 3-x Cu x In2S 6-y O y The catalyst was named ZCISO.

[0009] Where x=0.05, y=0.56.

[0010] On the other hand, the present invention provides a novel Zn for photosynthetic hydrogen peroxide. 3-x Cu x In2S 6-y O y The catalyst was prepared using the method described above.

[0011] On the other hand, the present invention provides a novel Zn for photosynthetic hydrogen peroxide. 3-x Cu x In2S 6-y O y Application of catalysts in photocatalytic H2O2 production.

[0012] Compared with the prior art, the specific beneficial effects of the present invention are as follows:

[0013] 1. This invention provides a novel Zn for the photosynthesis of hydrogen peroxide. 3-x Cu x In2S 6-y O y The catalyst preparation method is controllable, precise, easily reproducible, and enables gram-scale production of Zn. 3-x Cu x In2S 6-y O y The catalyst exhibits higher catalytic activity and stability than Zn3In2S6. More importantly, this method also provides a new inspiration for the design of novel two-dimensional sulfide-based materials.

[0014] 2. The novel Zn provided by this invention 3-x Cu x In2S 6-y O y and Zn 3-x Cux In2S6 exhibits the typical morphology of a two-dimensional sulfide. When exposed to light, it was found that electrons and holes can undergo efficient and directional separation and transfer.

[0015] 3. The Zn provided by this invention 3-x Cu x In2S 6-y O y It can be applied in the field of photocatalytic H2O2 production, achieving unprecedented performance in sulfides. The produced H2O2 can be directly used for the degradation of pollutants. Under outdoor sunlight, the produced H2O2 can be used for sterilization with an effect close to 100%, and it can also be recycled.

[0016] 4. The novel Zn provided by this invention 3-x Cu x In2S 6-y O y This not only fills the gaps in current two-dimensional sulfide modification strategies, but also provides novel materials and methods for the application of two-dimensional sulfides in fields such as sustainable energy, catalysis, and environmental medicine. Attached Figure Description

[0017] Figure 1 Electron paramagnetic resonance (EPR) spectra and photoelectron spectroscopy (PES) spectra of the samples provided in the embodiments of the present invention; a is the EPR spectrum of three samples, b is the PES spectrum of ZIS (Zn3In2S6, named ZIS), and c is the PES spectrum of ZCIS (Zn... 3- x Cu x The photoelectron spectrum of In2S6 (x = 0.05, named ZCIS), where d represents ZCISO (Zn 3-x Cu x In2S 6-y O y The photoelectron spectrum of the image (x and y are 0.05 and 0.56 respectively, named ZCISO);

[0018] Figure 2 Scanning electron microscope images of samples provided in embodiments of the present invention; a is ZIS, b is ZCIS, c is ZCISO;

[0019] Figure 3 X-ray diffraction patterns of three samples provided in embodiments of the present invention;

[0020] Figure 4 The results of the electrochemical selectivity of hydrogen peroxide ring disk performance and the number of electrons transferred are provided for three samples in the embodiments of the present invention; a is the rotating ring disk performance data, b is the corresponding number of electrons transferred;

[0021] Figure 5 The performance results of the three samples under Kelvin probe force microscope in the dark and under illumination for the embodiments of the present invention are shown below; a, b, and c are surface potential diagrams of the three samples under dark conditions, d, e, and f are surface potential diagrams of the three samples under illumination conditions, and g, h, and i are line graphs of the raw data extracted from the three samples under illumination and darkness conditions, comparing their respective dark and illuminated conditions.

[0022] Figure 6 The following are the photocatalytic H2O2 production performance results, decomposition performance results, and degradation results of three samples provided in the embodiments of the present invention; a is the H2O2 yield graph, b is the decomposition data graph, and c is the comparison of the effect of using the produced H2O2 to degrade pollutants;

[0023] Figure 7 This invention provides an apparatus for the outdoor catalytic production of H2O2.

[0024] Figure 8 The following are the performance results and sterilization results of outdoor H2O2 production by ZCISO provided in the embodiments of the present invention; a is a graph of H2O2 production data at different time periods, and b is a comparison of sterilization effects. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0026] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0027] Example 1: A novel Zn-based method for the photosynthesis of hydrogen peroxide 3-x Cu x In2S 6-y O y (x and y are 0.05 and 0.56 respectively, named ZCISO), its preparation method includes the following steps:

[0028] 6 mmol ZnSO4·7H2O and 4 mmol InCl3·4H2O were dissolved in 70 mL of deionized water and stirred for 30 minutes. Then, 17 mg CuCl2 was added to the solution, and stirring continued for 15 minutes. Finally, 24 mmol thioacetamide was added, and the mixture was stirred for 30 minutes. The mixture was then transferred to a 100 mL PTFE-lined stainless steel reactor. The reaction time and temperature were set to 12 hours and 160 °C, respectively. After cooling to room temperature, the precipitate was collected by centrifugation, washed three times with distilled water and ethanol, and then dried in a vacuum oven at 60 °C. The sample at this point was ZnSO4·7H2O. 3-x Cux In2S6, with x = 0.05, was named ZCIS. The sample was then heat-treated in air at 350 °C for 2 hours at a heating rate of 5 °C / min. The resulting sample was named ZCISO, and the yield of the sample was approximately 1.2 g.

[0029] Comparative Example 1, Zn3In2S6 (named ZIS), was prepared by the following steps:

[0030] 6 mmol ZnSO4·7H2O and 4 mmol InCl3·4H2O were dissolved in 70 mL of deionized water and stirred for 30 minutes. Then, 24 mmol thioacetamide was added and stirred for another 30 minutes. The mixture was then transferred to a 100 mL PTFE-lined stainless steel reactor. The reaction time and temperature were set to 12 hours and 160 °C, respectively. After cooling to room temperature, the precipitate was collected by centrifugation, washed three times with distilled water and ethanol, and then dried in a vacuum oven at 60 °C.

[0031] Performance Analysis:

[0032] 1. The three samples, ZCIS and ZCISO from Example 1 and ZIS from Comparative Example 1, were analyzed to obtain electron paramagnetic resonance (EPR) and photoelectron spectroscopy (XPS) spectra, as shown below. Figure 1 As shown, the comparison between ZCISO and ZIS clearly shows the signal of divalent Cu and lattice oxygen, proving the successful introduction of Cu and O.

[0033] The obtained scanning electron microscope images are as follows Figure 2 As shown, it can be seen that the morphology of ZCISO has not changed significantly, indicating that the strategy of the embodiment of the present invention does not affect the basic morphology of the original ZCIS.

[0034] The X-ray diffraction pattern obtained is as follows Figure 3 As shown, the results are similar to those of scanning electron microscopy, with the three samples exhibiting almost identical lines, further proving that the ZCISO structure is well preserved.

[0035] 2. The electrochemical selectivity of hydrogen peroxide on the three samples was tested, and the steps are as follows:

[0036] 10 mg of sample was dispersed in 2 mL of a water-isopropanol mixture (1:1 v / v) containing 100 μL of Nafion solution (5 wt%) and sonicated for 20 minutes. Then, 10 μL of the dispersion was pipetted onto a ring-disk electrode, with a Pt electrode as the counter electrode, Ag / AgCl (saturated KCl) as the reference electrode, and 0.5 M Na2SO4 aqueous solution as the electrolyte. The number of electrons transferred (n) was calculated using the following formula:

[0037] ;

[0038] The selectivity of H2O2 is calculated using the following formula:

[0039] ;

[0040] In the two formulas above, It is loop current. It is disk current. The collection efficiency is 0.37;

[0041] The calculation results are as follows Figure 4 As shown, ZCISO has better oxygen activation ability, which is crucial to the performance of H2O2 production.

[0042] 3. The performance of the three samples under Kelvin probe force microscopy in both dark and light conditions was tested. Kelvin probe force microscopy can measure the surface potential of the sample, and the larger the potential difference under light and darkness, the stronger the electron-hole separation effect. The sample was dispersed in alcohol, ultrasonically homogenized, and then dropped onto a conductive glass to form a uniform film. The film was then placed in the test chamber, and the surface potential of the sample was recorded by comparing the conditions under dark and light conditions. The average potential difference was then plotted and calculated. The results are shown below. Figure 5 As shown, the potential difference of ZCISO is more than 10 times that of ZIS.

[0043] 4. The photocatalytic H2O2 production performance of the three samples was tested, and the steps are as follows:

[0044] Photocatalytic H2O2 production was carried out in a 30 mL aqueous suspension containing 3 mg of sample, with oxygen continuously introduced throughout the reaction, using a xenon lamp equipped with a 420 nm cutoff filter (illuminance: 100 mW cm⁻¹). -2 The mixture was irradiated, and the reaction temperature was maintained at 15 °C using a circulating water bath. The concentration of H2O2 was determined by iodometric titration, and the results were as follows: Figure 6 As shown in Figure a;

[0045] Furthermore, a hydrogen peroxide decomposition experiment was conducted, with the following steps:

[0046] 3 mg of sample was added to 30 mL of 0.3 mM H2O2 solution, followed by 30 minutes of argon purging in the reactor. The concentration of H2O2 at this time was recorded. The reaction was then carried out with the lamp turned on, and argon purging continued. The concentration of H2O2 was measured after 20 minutes of irradiation. The initial concentration of H2O2 was denoted as C0, and the concentration after the reaction was denoted as C. The decomposition of H2O2 followed first-order kinetics, and the decomposition rate constant (K) was... d min -1 The following formula can be used to calculate:

[0047] ;

[0048] Where t is the reaction time;

[0049] The theoretical formation rate constant of H2O2 (K) f , μM min -1 ) Use the following formula to calculate:

[0050] ;

[0051] in, The final concentration of H2O2 produced is K, t is the reaction time, and K is the concentration of H2O2 produced. d It is the decomposition rate constant;

[0052] The results are as follows Figure 6 As shown in Figure b, it can be seen that ZCISO has a very weak decomposition effect on H2O2, indicating that it can effectively stabilize the catalytic products.

[0053] The produced H2O2 was extracted (and separated from the catalyst), and experiments were conducted to reduce pollutants. The results are as follows: Figure 6 As shown in Figure c, it can be seen that the produced H2O2 can effectively degrade pollutants such as Rhodamine B and methyl orange.

[0054] 5. Outdoor production H2O2 performance testing was conducted on sample ZCISO using methods such as... Figure 7 The apparatus shown was used to evaluate the performance of hydrogen peroxide over a 5-hour period from 10:00 AM to 3:00 PM on a sunny day, with concentration determination performed hourly. The results are as follows: Figure 8 As shown in Figure a, it can be seen that H2O2 can be produced continuously and stably throughout the day;

[0055] Subsequently, H2O2 (purified hydrogen peroxide after catalyst separation) was extracted and used in a sterilization experiment. The specific bacteria used were: *Rhodospirillum rubrum*, *Escherichia coli* K12, and *Alcaligenes eutrophus*, all purchased from Ningbo Mingzhou Biotechnology Co., Ltd. Bacterial growth was documented through photographs. Figure 8As shown in Figure b, the generated H2O2 was found to effectively kill Rhodospirillum, Alcaligenes, and Escherichia coli.

[0056] 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, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A novel Zn-based photosynthetic hydrogen peroxide 3-x Cu x In2S 6-y O y A method for preparing a catalyst, characterized in that, Includes the following steps: Dissolve ZnSO4·7H2O and InCl3·4H2O in deionized water, stir, add CuCl2, continue stirring, and finally add thioacetamide. After stirring, transfer the mixture to a polytetrafluoroethylene-lined stainless steel reactor for reaction. After the reaction was complete, the mixture was cooled to room temperature, centrifuged to collect the precipitate, washed several times, and dried to obtain Zn. 3-x Cu x In2S6, named ZCIS, is then heat-treated in air to obtain Zn. 3-x Cu x In2S 6-y O y The catalyst was named ZCISO. Where x=0.05, y=0.

56.

2. The novel Zn photosynthetic hydrogen peroxide according to claim 1 3-x Cu x In2S 6-y O y A method for preparing a catalyst, characterized in that, The molar ratio of ZnSO4·7H2O, InCl3·4H2O, CuCl2 and thioacetamide is 6:4:0.126:

24.

3. The novel Zn for photosynthetic hydrogen peroxide according to claim 1 3-x Cu x In2S 6-y O y A method for preparing a catalyst, characterized in that, The step of transferring the mixture to a polytetrafluoroethylene-lined stainless steel reactor for reaction is carried out at a temperature of 155-165℃ for 12 hours.

4. The novel Zn photosynthetic hydrogen peroxide according to claim 1 3-x Cu x In2S 6-y O y A method for preparing a catalyst, characterized in that, The heat treatment is performed at a temperature of 345-355℃ for 2 hours.

5. The novel Zn photosynthetic hydrogen peroxide according to claim 4 3-x Cu x In2S 6-y O y A method for preparing a catalyst, characterized in that, The heating rate for the heat treatment is set to 5 °C / min.

6. A novel Zn-based method for the photosynthesis of hydrogen peroxide 3-x Cu x In2S 6-y O y Catalyst, characterized in that, It is prepared using the preparation method described in any one of claims 1-5.

7. A novel Zn for photosynthetic hydrogen peroxide as described in claim 6 3-x Cu x In2S 6-y O y Application of catalysts in photocatalytic H2O2 production.

8. The application according to claim 7, characterized in that, Includes the following steps: The Zn 3-x Cu x In2S 6-y O y The catalyst, acting as a photocatalyst, is added to water, and oxygen is continuously introduced while providing light to facilitate the photocatalytic production of H2O2.

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