Preparation method of indium tin sulfide / copper sulfide composite photocatalyst, product and application thereof
By preparing an indium tin sulfide/copper sulfide composite photocatalyst, the problems of weak adsorption and low separation efficiency of photogenerated carriers in the CO2 photoreduction process were solved, achieving a high-efficiency conversion of CO2 to CH4 with good stability and economy.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ZHEJIANG NORMAL UNIV
- Filing Date
- 2024-04-17
- Publication Date
- 2026-06-16
Smart Images
Figure CN118218005B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of photocatalytic CO2 reduction catalyst technology, and in particular to a method for preparing an indium tin sulfide / copper sulfide composite photocatalyst, its products, and applications. Background Technology
[0002] Since the Industrial Revolution, the widespread use of fossil fuels has led to a rapid increase in the concentration of the greenhouse gas CO2 in the atmosphere, causing an imbalance in the Earth's carbon cycle and triggering a series of climate and environmental problems. Achieving carbon neutrality by controlling greenhouse gas emissions has become one of the major challenges facing society today, and utilizing renewable energy to drive catalytic reactions to produce clean energy is widely considered by academia and industry as an important strategy for solving these problems. Photocatalysis, as a sustainable, environmentally friendly, and promising method, has been widely accepted in addressing both the increasingly severe energy shortage and environmental pollution. However, in the CO2 photoreduction process, the performance is still limited due to the weak adsorption of CO2 and the low separation efficiency of photogenerated carriers. Therefore, developing a photocatalyst to efficiently and artificially catalyze greenhouse gas CO2 and water into usable organic compounds such as CH4 and CO is one of the most ideal ways to simultaneously solve environmental pollution and the energy crisis.
[0003] Generally, improving photogenerated charge separation, increasing surface catalytic sites, and expanding the light absorption range are key steps in developing highly efficient photocatalysts. Metal sulfides are excellent visible-light-responsive semiconductors and have been extensively studied in photocatalysis. The crystal structure of single-metal sulfides can be flexibly adjusted by substituting different valence states and ionic radii at the metal center to form polymetallic sulfides. However, the rapid recombination of photoexcited charge carriers in single-component sulfides leads to unsatisfactory photocatalytic performance in practical applications. Transition metal sulfides possess unique energy, catalytic, and electrical properties, and have broad application prospects in photocatalytic reactions. For example, Chinese Patent Publication No. CN113368871A discloses a photocatalyst with atomically dispersed metal sites on its surface, and its disclosed cadmium sulfide catalyst improves the yield of photocatalytic carbon dioxide reduction.
[0004] Especially copper sulfide (Cu) 2-x Cu, as an important material, possesses excellent properties and has broad application prospects in electronic and photocatalyst fields. Meanwhile, due to Cu... 2-x S has an additional absorption band in the near-infrared region, and its metallic localized surface plasmon resonance (LSPR) behavior is due to Cu 2-xThis is caused by the presence of Cu vacancies in S. For example, Chinese Patent CN116099553A discloses a method for preparing a catalyst for the photocatalytic reduction of carbon dioxide to produce methane, which includes the following steps: preparing a copper mesh dispersion; mixing a binder and clay, adding a soluble salt of manganese to obtain a mixed solution; mixing the copper mesh dispersion with the above mixed solution, hydrothermally treating, drying, and placing it in a tube furnace for sealed heating to obtain a copper mesh catalyst with manganese oxide loaded on its surface; loading molybdenum disulfide and copper sulfide onto the surface of the copper mesh catalyst with manganese oxide loaded on its surface by electrodeposition to obtain an active catalyst; placing it under an argon or N2 atmosphere for crystallization and drying to obtain a catalyst for the photocatalytic reduction of carbon dioxide to produce methane.
[0005] Therefore, how to use Cu 2-x Combining S with other catalysts to construct highly efficient and stable photocatalysts to improve photocatalytic performance is currently a research hotspot in this field. Summary of the Invention
[0006] The purpose of this invention is to provide a method for preparing an indium tin sulfide / copper sulfide composite photocatalyst, which exhibits good performance in photocatalytic CO2 reduction.
[0007] This invention provides the following solution:
[0008] A method for preparing an indium tin sulfide / copper sulfide composite photocatalyst, the method comprising: using SnIn4S8 nanosheets as templates, dispersing them in a solvent, adding anhydrous copper chloride and sodium sulfide nonahydrate, and heating to react to obtain the indium tin sulfide / copper sulfide composite material.
[0009] Furthermore, the mass ratio of SnIn4S8 nanosheets to copper sulfide in the indium tin sulfide / copper sulfide composite photocatalyst is 1:0.25-2. The heating temperature is 160-200℃.
[0010] More preferably, the preparation method includes: dispersing SnIn4S8 nanosheets in ethylene glycol, ultrasonically homogenizing and mixing, magnetically stirring for 20-30 minutes, adding different proportions of anhydrous copper chloride (CuCl2) and sodium sulfide nonahydrate (Na2S·9H2O), ultrasonically homogenizing, magnetically stirring for 20-30 minutes, transferring the above mixed solution to a reaction vessel, reacting at 160-200℃ for 24 hours, and after naturally cooling to room temperature, opening the reaction vessel, washing with deionized water and anhydrous ethanol, centrifuging, and drying in an oven at 80℃.
[0011] Furthermore, the preparation method of the SnIn4S8 nanosheets includes: adding tin tetrachloride pentahydrate, indium trichloride tetrahydrate, and a sulfur source to a solvent, dissolving them, and then reacting them at 120-180℃ to obtain SnIn4S8 nanosheets. This invention controls the reaction temperature to synthesize nanosheets with varying morphologies.
[0012] More preferably, the sulfur source is thioacetamide (C2H5NS), thiourea (CH4N2S), or L-cysteine (C3H7NO2S).
[0013] More preferably, the molar ratio of tin tetrachloride pentahydrate, indium trichloride tetrahydrate, and the sulfur source is 1:4:8-10. Indium tin sulfide cannot be successfully synthesized if the stoichiometric ratio is lower than the above.
[0014] More preferably, the preparation method of the SnIn4S8 nanosheets specifically includes the following steps: adding tin tetrachloride pentahydrate (SnCl4·5H2O), indium trichloride tetrahydrate (InCl4·4H2O), and thioacetamide (C2H5NS) to 40ml of ethylene glycol, mixing, sonicating until homogeneous, and magnetically stirring for 30-60min to obtain a mixed solution, transferring the above mixed solution to a 50mL reaction vessel, reacting at 120-180℃ for 4h, and after naturally cooling to room temperature, opening the reaction vessel, washing with deionized water and anhydrous ethanol, centrifuging, and drying in an 80℃ vacuum oven.
[0015] More preferably, the Cu 2-x The preparation method of S nanoparticles specifically includes the following steps: anhydrous copper chloride (CuCl2) and sodium sulfide nonahydrate (Na2S·9H2O) are added to 40mL of ethylene glycol, ultrasonically homogenized, and magnetically stirred for 20-30 minutes to obtain a mixed solution. The above mixed solution is transferred to a 50mL reaction vessel, reacted at 180℃ for 24h, and after naturally cooling to room temperature, the reaction vessel is opened, washed with deionized water and anhydrous ethanol, centrifuged, and dried in a vacuum oven at 80℃.
[0016] More preferably, the mass ratio of anhydrous copper chloride (CuCl2) to sodium sulfide nonahydrate (Na2S·9H2O) is 1:1.70.
[0017] The preparation method provided by this invention provides a simple and easy synthetic route for preparing SnIn4S8 / Cu for the photoreduction synthesis of CO and / or CH4 from CO2. 2-x S nanocomposite photocatalysts, SnIn4S8-based heterostructures slow down the recombination of photogenerated carriers, and the prepared SnIn4S8 / Cu 2-x The S nanocomposite photocatalyst exhibits excellent catalytic performance and high cycle stability, and can be used for photocatalytic CO2 reduction.
[0018] The preparation method provided by this invention can further optimize light absorption capacity and promote the separation efficiency of photogenerated electron-hole pairs by controlling the catalyst morphology (reaction temperature of SnIn4S8 nanosheets) and component ratio (mass ratio of SnIn4S8 nanosheets to copper sulfide), thereby regulating and improving the photocatalytic CO2 reduction performance and product selectivity.
[0019] The present invention also provides an indium tin sulfide / copper sulfide composite photocatalyst prepared according to the above preparation method.
[0020] Furthermore, the diameter of the indium tin sulfide / copper sulfide composite photocatalyst is 450–500 nm.
[0021] The present invention also provides an application of the above-mentioned indium tin sulfide / copper sulfide composite material photocatalyst in the photocatalytic reduction of CO2 to CO and / or CH4.
[0022] Furthermore, the indium tin sulfide / copper sulfide composite photocatalyst is applied to the photocatalytic reduction of CO2 to CH4. Specifically, the selectivity and formation rate of CH4 are both higher than those of CO.
[0023] More preferably, when the mass ratio of SnIn4S8 nanosheets to copper sulfide in the indium tin sulfide / copper sulfide composite photocatalyst is 1:0.5-2, the CH4 precipitation rate is 5.69-21.52 μmol g. -1 h -1 The selectivity for CH4 was 45.6-70.1%.
[0024] More preferably, when the mass ratio of SnIn4S8 nanosheets to copper sulfide in the indium tin sulfide / copper sulfide composite photocatalyst is 1:1, the CO evolution rate is 8.02 μmol g. -1 h -1 The CH4 precipitation rate was 21.52 μmol g. -1 h -1 The selectivity for photocatalytic CO2 reduction to CH4 is 70.1%, and it can maintain stable catalytic performance for 15 hours.
[0025] Compared with the prior art, the present invention has the following superior effects:
[0026] The preparation method provided by this invention has advantages such as high reproducibility, simple synthesis process, inexpensive raw materials, and low cost of photocatalyst preparation. The SnIn4S8 / Cu prepared by this invention... 2-xS nanocomposite photocatalysts improve the utilization rate of visible light, enhance photocatalytic efficiency, and exhibit good stability by combining sheet-like structures with nanoparticles; in particular, they improve the selectivity, precipitation rate, and stability of photocatalytic CO2 reduction to CH4. Attached Figure Description
[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0028] Figure 1 The XRD patterns of the products prepared in Example 3 and Comparative Examples 1-2 are shown, where: the horizontal axis X is the diffraction angle (2θ), and the vertical axis Y is the relative diffraction intensity.
[0029] Figure 2 SnIn4S8 / Cu prepared in Example 3 2-x Morphology of S nanocomposite photocatalyst;
[0030] Figure 3 The SnIn4S8 / Cu-based materials prepared in Examples 1-5 2-x S nanocomposites, SnIn4S8 nanosheets prepared in Comparative Example 1 and Cu prepared in Comparative Example 2 2-x Test results of the photocatalytic CO2 to CO conversion performance of S nanoparticles;
[0031] Figure 4 The SnIn4S8 / Cu-based materials prepared in Examples 1-5 2-x S nanocomposites, SnIn4S8 nanosheets prepared in Comparative Example 1 and Cu prepared in Comparative Example 2 2-x Test results of the photocatalytic CO2 to CH4 production performance of S nanoparticles;
[0032] Figure 5 The SnIn4S8 / Cu prepared in Example 1 2-x Test results of the photocatalytic CO2 reduction cycle performance of S nanocomposite materials. Detailed Implementation
[0033] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.
[0034] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.
[0035] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.
[0036] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be readily apparent to those skilled in the art. This specification and embodiments are merely exemplary.
[0037] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.
[0038] The X-ray diffractometer used in the embodiments of the present invention is a Bruker D8 X-ray diffractometer from the United States, and the scanning electron microscope used is a Zeiss GeminiSEM 300 field emission scanning electron microscope (FE-SEM) from Germany.
[0039] Example 1 SnIn4S8 / Cu 2-x Preparation of S-1 nanocomposite materials
[0040] Preparation of SnIn4S8 nanosheets: 0.15 mmol of tin tetrachloride pentahydrate (SnCl4·5H2O), 0.6 mmol of indium trichloride tetrahydrate (InCl4·4H2O), and 1.5 mmol of thioacetamide (C2H5NS) were added to 40 mL of ethylene glycol and mixed. The mixture was sonicated and magnetically stirred for 1 h to obtain a mixed solution. The mixed solution was transferred to a 50 mL reactor and reacted at 160 °C for 4 h. After naturally cooling to room temperature, the reactor was opened, washed with deionized water and anhydrous ethanol, centrifuged, and dried in a vacuum oven at 80 °C.
[0041] 50 mg of SnIn4S8 nanosheets were dispersed in 40 ml of ethylene glycol, sonicated until homogeneous, and then mixed. The mixture was magnetically stirred for 30 minutes. 0.0135 g of anhydrous copper chloride (CuCl2) and 0.0229 g of sodium sulfide nonahydrate (Na2S·9H2O) were added, sonicated until homogeneous, and magnetically stirred for 30 minutes. The mixture was then transferred to a reaction vessel and reacted at 180 °C for 24 h. After naturally cooling to room temperature, the reaction vessel was opened, and the mixture was washed with deionized water and anhydrous ethanol, centrifuged, and dried in an oven at 80 °C.
[0042] In this embodiment, the mass ratio of SnIn4S8 nanosheets to copper sulfide was 1:0.25.
[0043] Example 2 SnIn4S8 / Cu 2-x Preparation of S-2 nanocomposite materials
[0044] 50 mg of SnIn4S8 nanosheets prepared in Example 1 were dispersed in 40 ml of ethylene glycol, sonicated until homogeneous, and then mixed. The mixture was magnetically stirred for 30 minutes. 0.0269 g of anhydrous copper chloride (CuCl2) and 0.0457 g of sodium sulfide nonahydrate (Na2S·9H2O) were added, sonicated until homogeneous, and magnetically stirred for 30 minutes. The mixture was then transferred to a reaction vessel and reacted at 180 °C for 24 h. After naturally cooling to room temperature, the reaction vessel was opened, and the mixture was washed with deionized water and anhydrous ethanol, centrifuged, and dried in an oven at 80 °C.
[0045] In this embodiment, the mass ratio of SnIn4S8 nanosheets to copper sulfide was 1:0.5.
[0046] Example 3 SnIn4S8 / Cu 2-x Preparation of S-3 nanocomposite materials
[0047] 50 mg of SnIn4S8 nanosheets prepared in Example 1 were dispersed in 40 ml of ethylene glycol, sonicated until homogeneous, and then mixed. The mixture was magnetically stirred for 30 minutes. 0.0538 g of anhydrous copper chloride (CuCl2) and 0.0914 g of sodium sulfide nonahydrate (Na2S·9H2O) were added, sonicated until homogeneous, and magnetically stirred for 30 minutes. The mixture was then transferred to a reaction vessel and reacted at 180 °C for 24 h. After naturally cooling to room temperature, the reaction vessel was opened, and the mixture was washed with deionized water and anhydrous ethanol, centrifuged, and dried in an oven at 80 °C.
[0048] In this embodiment, the mass ratio of SnIn4S8 nanosheets to copper sulfide was 1:1.
[0049] The XRD test results of the sample prepared in this embodiment show that: Figure 1 As shown, the x-axis represents the diffraction angle (2θ), and the y-axis represents the relative diffraction intensity. Its diffraction peaks correspond to single SnIn4S8 and Cu peaks. 2-xS and SnIn4S8 / Cu 2-x S.
[0050] For the SnIn4S8 / Cu prepared in this embodiment 2-x Field emission scanning electron microscopy (SEM) analysis was performed on the S-3 nanocomposite photocatalyst, and the resulting electron micrographs are shown below. Figure 2 As shown, the heterostructure of nanoparticles loaded on the nanosheet can be seen. This embodiment prepared the SnIn4S8 / Cu... 2-x The diameter range of the S-3 nanocomposite photocatalyst is 450–500 nm.
[0051] Example 4 SnIn4S8 / Cu 2-x Preparation of S-4 nanocomposite materials
[0052] 50 mg of SnIn4S8 nanosheets prepared in Example 1 were dispersed in 40 ml of ethylene glycol, sonicated until homogeneous, and then mixed. The mixture was magnetically stirred for 30 minutes. 0.0807 g of anhydrous copper chloride (CuCl2) and 0.1371 g of sodium sulfide nonahydrate (Na2S·9H2O) were added, sonicated until homogeneous, and magnetically stirred for 30 minutes. The mixture was then transferred to a reaction vessel and reacted at 180 °C for 24 h. After naturally cooling to room temperature, the reaction vessel was opened, and the mixture was washed with deionized water and anhydrous ethanol, centrifuged, and dried in an oven at 80 °C.
[0053] In this embodiment, the mass ratio of SnIn4S8 nanosheets to copper sulfide was 1:1.5.
[0054] Example 5 SnIn4S8 / Cu 2-x Preparation of S-5 nanocomposite materials
[0055] 50 mg of SnIn4S8 nanosheets prepared in Example 1 were dispersed in 40 ml of ethylene glycol, sonicated until homogeneous, and then mixed. The mixture was then magnetically stirred for 30 minutes. 0.1076 g of anhydrous copper chloride (CuCl2) and 0.1828 g of sodium sulfide nonahydrate (Na2S·9H2O) were added, sonicated until homogeneous, and then magnetically stirred for 30 minutes. The mixture was then transferred to a reaction vessel and reacted at 180 °C for 24 h. After naturally cooling to room temperature, the reaction vessel was opened, and the mixture was washed with deionized water and anhydrous ethanol, centrifuged, and dried in an oven at 80 °C.
[0056] In this embodiment, the mass ratio of SnIn4S8 nanosheets to copper sulfide is 1:2.
[0057] Comparative Example 1: Preparation of SnIn4S8 Nanosheets
[0058] 0.15 mmol of tin tetrachloride pentahydrate (SnCl4·5H2O), 0.6 mmol of indium trichloride tetrahydrate (InCl4·4H2O), and 1.5 mmol of thioacetamide (C2H5NS) were added to 40 mL of ethylene glycol and mixed. The mixture was sonicated and magnetically stirred for 1 h to obtain a mixed solution. The mixed solution was transferred to a 50 mL reactor and reacted at 160 °C for 4 h. After naturally cooling to room temperature, the reactor was opened, washed with deionized water and anhydrous ethanol, centrifuged, and dried in a vacuum oven at 80 °C.
[0059] Comparative Example 2Cu 2-x Preparation of S nanoparticles
[0060] 0.0538g of anhydrous copper chloride (CuCl2) and 0.0914g of sodium sulfide nonahydrate (Na2S·9H2O) were added to 40mL of ethylene glycol, sonicated until homogeneous, and magnetically stirred for 30 minutes to obtain a mixed solution. The mixed solution was transferred to a 50mL reactor and reacted at 180℃ for 24h. After naturally cooling to room temperature, the reactor was opened, washed with deionized water and anhydrous ethanol, centrifuged, and dried in a vacuum oven at 80℃.
[0061] Photocatalytic CO2 reduction test:
[0062] SnIn4S8 / Cu prepared in Examples 1-5 2-x S nanocomposite photocatalyst and SnIn4S8 nanosheets and Cu prepared in Comparative Examples 1-2 2-x Photocatalytic CO2 reduction test using S nanoparticles: 5 mg of catalyst was dispersed in 2 ml of water and sonicated for 5 min until homogeneous. The mixture was then dispersed on a 40 mm glass fiber filter membrane and dried in a 60 °C oven. The glass fiber filter membrane containing the sample was fixed on a tripod and placed in a Pyrex reaction vessel along with 2 ml of deionized water. The reaction vessel was evacuated three times, and then high-purity CO2 (99.999%) was pumped in to approximately 80 kPa. The temperature of the entire reaction system was maintained at 25 °C by circulating condensate. Gas phase products were collected every 0.5 h and analyzed using an online gas chromatograph (Shimadzu GC-2014, Ar as carrier gas) equipped with a flame ionization detector (FID) and a thermal conductivity detector to determine the relevant gas types and contents. The photocatalytic CO2 reduction cycle stability test was basically the same as the above operation, except that after every 3 h of testing, the vacuum was re-evacuated and then high-purity CO2 gas was pumped in to avoid affecting the accuracy of the next detection.
[0063] SnIn4S8 / Cu prepared in Examples 1-5 2-x The photocatalytic CO2 reduction to CO performance test of S nanocomposite materials is as follows: Figure 3As shown, under visible light irradiation, the SnIn4S8 / Cu prepared in Example 3... 2-x The photocatalytic reduction rate of CO2 to CO using S-3 is 8.02 μmol g. -1 h -1 It is Cu 2-x S(6.33μmol g -1 h -1 1.27 times that of ).
[0064] SnIn4S8 / Cu prepared in Examples 1-5 2-x Performance testing of S nanocomposite materials in photocatalytic CO2 reduction to CH4 generation: Figure 4 As shown, under visible light irradiation, the SnIn4S8 / Cu prepared in Example 3... 2-x S-3 exhibits the highest CH4 yield, with a CH4 production rate of 21.52 μmol g during photocatalytic CO2 reduction. -1 h -1 .
[0065] SnIn4S8 / Cu prepared in Example 3 2-x The test results of the photocatalytic CO2 reduction cycle performance of S-3 nanocomposite material are as follows: Figure 5 As shown.
[0066] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.
Claims
1. The application of an indium tin sulfide / copper sulfide composite photocatalyst in the photocatalytic reduction of CO2 to CO and / or CH4, characterized in that, The preparation method of the indium tin sulfide / copper sulfide composite photocatalyst includes: using SnIn4S8 nanosheets as templates, dispersing them in a solvent, adding anhydrous copper chloride and sodium sulfide nonahydrate, and heating to react to obtain the indium tin sulfide / copper sulfide composite material. The mass ratio of SnIn4S8 nanosheets to copper sulfide in the indium tin sulfide / copper sulfide composite material is 1:0.25-2; the heating temperature is 160-200℃; and the diameter of the indium tin sulfide / copper sulfide composite photocatalyst is 450-500 nm.
2. The application according to claim 1, characterized in that, The preparation method of the SnIn4S8 nanosheets includes: adding tin tetrachloride pentahydrate, indium trichloride tetrahydrate and a sulfur source into a solvent, dissolving them and reacting them at 120-180℃ to obtain SnIn4S8 nanosheets.
3. The application according to claim 2, characterized in that, The sulfur source is thioacetamide (C2H5NS), thiourea (CH4N2S), or L-cysteine (C3H7NO2S).
4. The application according to claim 2, characterized in that, The molar ratio of tin tetrachloride pentahydrate, indium trichloride tetrahydrate, and sulfur source is 1:4:8-10.