An ordered mesoporous tungsten disulfide semiconductor material, a preparation method and application thereof

Abstract

The application discloses an ordered mesoporous tungsten disulfide semiconductor material and a preparation method and application thereof. The application adopts an amphiphilic block copolymer as an organic template agent, a polyoxometalate cluster as a tungsten source, and performs co-assembly in a double solvent system (an organic solvent / water) to obtain spherical core-shell composite micelles. After solvent evaporation, the micelles are deposited on a substrate to obtain an organic-inorganic composite film. The organic-inorganic composite film is first calcined at high temperature in an air atmosphere to obtain mesoporous tungsten trioxide. Then, the mesoporous tungsten trioxide is high-temperature sulfurized and reduced in an inert atmosphere by using sulfur powder as a sulfur source to obtain the ordered mesoporous tungsten disulfide material. The raw material is easy to obtain, the preparation process is simple, easy to repeat, and easy to control, the preparation parameters are easy to adjust, and the large-scale production can be easily realized.

Description

Technical Field

[0001] This invention relates to an ordered mesoporous tungsten disulfide semiconductor material, its preparation method and application, belonging to the field of advanced nanoporous materials. Background Technology

[0002] With the further development of science and technology and the economy and society, the demand for high-performance sensors is increasing. Among them, gas sensors have shown great promise in health monitoring, the Internet of Things, smart homes, and smart city construction, attracting close attention from researchers (see Nat. Mater. 2020, 19, 203.; ACS Nano 2022, 16, 17778.; Chem. Soc. Rev. 2022, 51, 7260.; Nano lett., 2013 ,13, 2.). Mesoporous materials, due to their advantages such as high porosity and high specific surface area, are widely used in gas sensing, adsorption separation, catalysis, and other fields. Tungsten disulfide (WS2), as a transition metal chalcogenide material, has a layered structure similar to graphene and features high carrier mobility and good mechanical properties. Due to its porous structure and the unique electronic structure and surface properties of transition metal sulfides, mesoporous tungsten disulfide holds promise for applications in high-performance gas sensors (see Adv. Energy Mater. 2016, 1501814). Currently, numerous ordered mesoporous metal oxide materials are used in gas sensing, such as mesoporous WO3, Al2O3, SnO2, MoO3, TiO2, and ZnO (see Small 2023, 2301011; Chem. Mater. 2016, 28, 7997; ACS Cent. Sci. 2022, 8, 1196; Chin. Chem. Lett. 2021, 32, 1994). However, there are currently few reports on the synthesis of mesoporous tungsten disulfide materials and their applications in semiconductor gas sensors. Summary of the Invention

[0003] Objectives of the Invention: The first objective of this invention is to provide an ordered mesoporous tungsten disulfide semiconductor material; the second objective is to provide a method for preparing the ordered mesoporous tungsten disulfide semiconductor material; and the third objective is to provide the application of the ordered mesoporous tungsten disulfide semiconductor material in the preparation of gas sensors, photocatalysis, and photoelectric detection.

[0004] Technical Solution: The present invention discloses an ordered mesoporous tungsten disulfide material, wherein the ordered mesoporous tungsten disulfide material is prepared by using an amphiphilic block copolymer as a template agent and polyoxometalates (POMs) as precursors. The hydrophilic segments of the amphiphilic block copolymer and the polyoxometalates self-assemble in a solvent through electrostatic attraction, causing the metal precursor to adsorb onto the template agent to form a microphase structure and an ordered mesoporous structure. The hydrophobic segments of the amphiphilic block copolymer aggregate in the solvent to form spherical micelles with hydrophobic segments as the core and hydrophilic segments as the shell. The material is obtained by calcining under Ar atmosphere to remove the template agent and decompose the polyoxometalates, followed by calcining in air to remove carbon and then sulfiding.

[0005] Furthermore, the ordered mesoporous tungsten disulfide material has a pore size of 10-50 nm and a wall thickness of 2-10 nm between the ordered mesopores.

[0006] The method for preparing the ordered mesoporous tungsten disulfide material of the present invention includes the following steps:

[0007] (1) Dissolve the amphiphilic block copolymer in an organic solvent and stir until homogeneous to obtain solution A; dissolve polyoxometalates (POMs) in deionized water and stir until homogeneous to obtain homogeneous solution B; mix solution A and solution B and stir until homogeneous to obtain homogeneous solution C.

[0008] (2) Spin-coat homogeneous solution C onto the substrate, evaporate at room temperature, and dry to obtain a substrate carrying the composite film;

[0009] (3) The substrate carrying the composite film was calcined in an argon atmosphere and then calcined in an air atmosphere to obtain an ordered mesoporous WO3 film material.

[0010] (4) The ordered mesoporous WO3 thin film material is placed in a tube furnace for sulfurization to obtain the ordered mesoporous tungsten disulfide material.

[0011] Further, in step (1), the organic solvent is one or more of N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMA), dimethyl sulfoxide (DMSO), and pyridine.

[0012] Further, in step (1), the hydrophilic segment of the amphiphilic block copolymer has a molecular weight of 2500-7500 g / mol and the hydrophobic segment has a molecular weight of 2500-37500 g / mol.

[0013] Furthermore, the amphiphilic block copolymer is polystyrene-polyethylene oxide (PS-) b -PEO), polyethylene oxide-polymethyl methacrylate (PEO- b -PMMA), polystyrene-poly4-vinylpyridine (PS-b -P4VP).

[0014] Further, in step (1), the polyoxometalate is one or more of ammonium metatungstate, ammonium phosphotungstate, silicotungstic acid, and phosphotungstic acid.

[0015] Further, in step (1), the mass ratio of the amphiphilic block copolymer to the polyoxometalate is 1:3-6.

[0016] Further, in step (1), the volume ratio of the deionized water to the organic solvent is 1:5-50.

[0017] Furthermore, in step (2), the substrate is a silicon wafer, a glass plate, or a petri dish.

[0018] Furthermore, in step (2), the time for evaporation at room temperature is 6-12 h.

[0019] Furthermore, in step (2), the drying temperature is 100-150 ℃ and the drying time is 12-24h.

[0020] Further, in step (3), the calcination under an argon atmosphere is to first raise the temperature to 350 ℃ at a heating rate of 1-3 ℃ / min, and then raise the temperature to 400-500 ℃ at a heating rate of 5-10 ℃ / min, and hold the temperature for 1-3 hours.

[0021] Further, in step (3), the temperature is increased to 350-400 ℃ at a heating rate of 5-10℃ / min during calcination in an air atmosphere, and calcined for 1-3 h.

[0022] Further, in step (4), the sulfidation is to place sulfur powder in a quartz crucible at one end of the gas inlet of the tubular furnace, place an ordered mesoporous WO3 thin film material in the center of the tubular furnace, and heat it to 350-450 ℃ at a heating rate of 5-10 ℃ / min, and hold it at that temperature for 0.5-1.0 h.

[0023] Furthermore, by changing the lengths of the hydrophobic and hydrophilic segments of the amphiphilic block copolymer, ordered mesoporous tungsten disulfide materials with different pore sizes, pore wall thicknesses, and specific surface areas can be synthesized.

[0024] Furthermore, by controlling the use of different polyoxometalates, ordered mesoporous tungsten disulfide materials with high crystallinity and high specific surface area, or ordered mesoporous tungsten disulfide materials doped with different elements, can be synthesized.

[0025] The application of the ordered mesoporous tungsten disulfide material described in this invention in the preparation of gas sensors.

[0026] This invention first utilizes an amphiphilic block copolymer as a template agent and polyoxometalates (POMs) as precursors. The hydrophilic segments and POMs self-assemble in a solvent through electrostatic attraction, causing the metal precursor to adsorb onto the template agent to form a microphase structure, which further develops into an ordered mesoporous structure. The hydrophobic segments aggregate in the solvent, forming spherical micelles with hydrophobic cores and hydrophilic shells. The template agent is removed by calcination under an Ar atmosphere, and the POMs are decomposed to obtain a mesoporous WO3 / C composite material. Further calcination in air to remove carbon yields an ordered mesoporous WO3 material. The obtained mesoporous WO3 is then further reduced by sulfur powder in a tube furnace to obtain a uniform mesoporous tungsten disulfide material. Since the molecular weight of the block copolymer and the calcination temperature have a significant impact on the pore size and crystallinity of mesoporous tungsten disulfide, the mesoporous tungsten disulfide material obtained by using this method and appropriately controlling the molecular weight of the block copolymer and the calcination temperature has a pore size between 10-50 nm, a pore wall size between 2-10 nm, and high crystallinity.

[0027] In this invention, low-temperature calcination with sp 2 A template agent with hybrid carbon-carbon double bonds generates an amorphous C-framework to support the formation of a mesoporous structure from the metal salt during high-temperature decomposition. Excess carbon is then removed by air calcination, yielding a pure mesoporous metal oxide structure. Unlike previous methods for generating tungsten disulfide films via chemical vapor deposition, this invention first generates a stable metal oxide structure before sulfurization with sulfur powder. By controlling the sulfurization growth temperature, partially to fully sulfurized mesoporous tungsten disulfide structures can be obtained, thereby improving the crystallinity of the mesoporous tungsten disulfide material.

[0028] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages:

[0029] (1) The ordered mesoporous tungsten disulfide material prepared by the present invention has the characteristics of high specific surface area, controllable pore size, high crystallinity, uniform crystallization, uniform pore wall and high carrier mobility, and has great application prospects in photocatalysis, photoelectric detection and gas sensing.

[0030] (2) Since direct synthesis of mesoporous tungsten disulfide is quite difficult, this invention first uses an amphiphilic block copolymer as a template agent to induce self-assembly of mesoporous tungsten trioxide film through solvent evaporation, and then uses sulfur powder for high-temperature sulfurization to reduce it to mesoporous tungsten disulfide film. The two-step synthesis of ordered mesoporous tungsten disulfide material has the advantages of readily available raw materials, simple operation, and easy reproducibility, and is suitable for large-scale production. Attached Figure Description

[0031] Figure 1 SEM image of the ordered mesoporous tungsten disulfide material prepared in Example 1;

[0032] Figure 2 Here is a high-resolution TEM image of the ordered mesoporous tungsten disulfide material prepared in Example 1;

[0033] Figure 3 The image shows the XRD pattern of the ordered mesoporous tungsten disulfide material prepared in Example 1.

[0034] Figure 4 The Raman spectrum of the ordered mesoporous tungsten disulfide material prepared in Example 1;

[0035] Figure 5 The image shows the room temperature NO2 gas sensing performance test results of the ordered mesoporous tungsten disulfide material prepared in Example 1. Detailed Implementation

[0036] The technical solution of the present invention will be further described below with reference to the accompanying drawings.

[0037] The reagents used in the following experiments:

[0038] Ammonium metatungstate, ammonium phosphotungstate, silicotungstic acid, phosphotungstic acid, N,N-dimethylformamide (DMF), and N,N-dimethylacetamide (DMA) were all purchased from Aladdin Reagent (Shanghai) Co., Ltd.

[0039] The sulfur powder was purchased from Sigma-Aldrich, Germany.

[0040] Amphiphilic block copolymer polystyrene-polyethylene oxide (PS-) b -PEO), polyethylene oxide-polymethyl methacrylate (PEO- b -PMMA), polystyrene-poly4-vinylpyridine (PS- b Purchased from Polymer Source (-P4VP).

[0041] Example 1: Preparation of ordered mesoporous tungsten disulfide materials

[0042] (1) 0.05 g of the amphiphilic block copolymer polystyrene-polyethylene oxide (PS-) b Dissolve 0.15 g of ammonium metatungstate in 4.5 mL of N,N-dimethylformamide (DMF) and stir with a magnetic stirrer to obtain a transparent solution A; dissolve 0.15 g of ammonium metatungstate in 0.5 mL of deionized water and stir to obtain a homogeneous solution B; mix the above solutions A and B and stir for 0.5 h to obtain a light blue transparent colloidal solution C.

[0043] (2) Take 1 mL of solution C and spin-coat it onto a silicon wafer (2×2 cm). 2 The solvent was evaporated at room temperature for 6 hours, and then the silicon wafer was transferred to a 100°C oven to further evaporate the solvent and cure for 12 hours to obtain a silicon wafer containing a light blue composite film.

[0044] (3) The silicon wafer containing the light blue composite film was placed in a tube furnace and calcined at 500 °C for 1 h in an argon atmosphere, with a heating rate of 1 °C / min before 350 °C and 5 °C / min after 350 °C. The calcined silicon wafer was then calcined in air at 400 °C for 1 h (heating rate of 5 °C / min) to obtain a silicon wafer containing ordered mesoporous WO3 thin film material.

[0045] (4) Place the silicon wafer containing ordered mesoporous WO3 thin film material in the middle of the tube furnace, weigh 0.3 g of sulfur powder into a ceramic boat, place it at the air inlet end (so that the temperature of the sulfur powder is maintained at 150-200 ℃), heat the tube furnace to 450 ℃ at a heating rate of 10 ℃ / min, and keep it at 450 ℃ for 1 h. After cooling, the ordered mesoporous tungsten disulfide material is obtained.

[0046] The ordered mesoporous tungsten disulfide material prepared in this embodiment was analyzed by scanning electron microscopy, and the results are as follows: Figure 1 As shown. Figure 1 The image shows a SEM image of the ordered mesoporous tungsten disulfide material prepared in Example 1. Figure 1 As can be seen, the ordered mesoporous tungsten disulfide material prepared in this embodiment has a periodically arranged ordered spherical mesoporous structure with a pore size of about 15 nm.

[0047] The ordered mesoporous tungsten disulfide material prepared in this embodiment was analyzed by transmission electron microscopy, and the results are as follows: Figure 2 As shown. Figure 2 Here is a high-resolution TEM image of the ordered mesoporous tungsten disulfide material prepared in Example 1. Figure 2 As can be seen, the ordered mesoporous tungsten disulfide material prepared in this embodiment has a clear mesoporous structure and lattice fringes, proving that the mesoporous framework has been highly crystallized.

[0048] XRD analysis was performed on the ordered mesoporous tungsten disulfide material prepared in this embodiment, and the results are as follows: Figure 3 As shown. Figure 3 The image shows the XRD pattern of the ordered mesoporous tungsten disulfide material prepared in Example 1. Figure 3 It can be seen that the ordered mesoporous tungsten disulfide material prepared in this embodiment shows three obvious diffraction peaks, corresponding to the (002), (100), and (110) crystal planes of tungsten disulfide (PDF#84-1398), indicating that a mesoporous tungsten disulfide material with a high degree of crystallinity was obtained.

[0049] Raman spectroscopy analysis was performed on the ordered mesoporous tungsten disulfide material prepared in this embodiment, and the results are as follows: Figure 4 As shown. Figure 4 The image shows the Raman spectrum of the ordered mesoporous tungsten disulfide material prepared in Example 1. Figure 4It can be seen that the ordered mesoporous tungsten disulfide material prepared in this embodiment exhibits good performance at 351 and 416 cm⁻¹. -1 Two distinct scattering peaks were observed, proving that pure WS2 material was obtained. Example 2

[0050] (1) 0.1 g of the amphiphilic block copolymer polyethylene oxide-polymethyl methacrylate (PEO- b Dissolve 0.30 g of ammonium phosphotungstate in 5 mL of N,N-dimethylacetamide (DMA) and stir with a magnetic stirrer to obtain a transparent solution A; dissolve 0.30 g of ammonium phosphotungstate in 1 mL of deionized water and stir to obtain a homogeneous solution B; mix the above solutions A and B and stir for 1 h to obtain a light blue transparent colloidal solution C.

[0051] (2) Take 2 mL of solution C and spin-coat it onto a glass slide (2×2 cm). 2 The solvent was evaporated at room temperature for 6 hours, and then the glass slide was transferred to a 100 °C oven for further evaporation and curing for 12 hours to obtain a glass slide containing a light blue composite film.

[0052] (3) The glass slide containing the light blue composite film was placed in a tube furnace and calcined at 500 °C for 1 h under an argon atmosphere, with a heating rate of 1 °C / min before 350 °C and 5 °C / min after 350 °C. The resulting sample was then calcined in air at 450 °C for 0.5 h (heating rate of 5 °C / min) to obtain a glass slide containing ordered mesoporous WO3 thin film material.

[0053] (4) Place the glass slide containing the ordered mesoporous WO3 thin film material in the middle of the tube furnace, weigh 1.0 g of sulfur powder into a ceramic boat, place it at the gas inlet end (so that the sulfur powder temperature is maintained at 150-200 ℃), heat the tube furnace to 350 ℃ at a heating rate of 10 ℃ / min, and keep it at 350 ℃ for 1 h. After cooling, the ordered mesoporous tungsten disulfide material is obtained. Example 3

[0054] (1) 0.05 g of the amphiphilic block copolymer polystyrene-poly4-vinylpyridine (PS- b Dissolve 0.175 g of silicotungstic acid in 1 mL of dimethyl sulfoxide (DMSO) and stir with a magnetic stirrer to obtain a transparent solution A; dissolve 0.175 g of silicotungstic acid in 1 mL of deionized water and stir to obtain a homogeneous solution B; mix the above solutions A and B and stir for 0.5 h to obtain a light blue transparent colloidal solution C.

[0055] (2) Take 5 mL of solution C and spread it evenly on a glass petri dish (10 cm in diameter). Let it evaporate at room temperature for 6 h. Then transfer the petri dish to a 100 ℃ oven to further evaporate the solvent and solidify for 12 h to obtain a petri dish containing a light blue composite film.

[0056] (3) The light blue composite membrane was scraped off from the petri dish and placed in a tube furnace. Under an argon atmosphere, it was calcined at 500 °C for 1 h with a heating rate of 1 °C / min before reaching 350 °C and 5 °C / min after reaching 350 °C. The resulting sample was then calcined in air at 400 °C for 0.5 h (heating rate of 5 °C / min) to obtain an ordered mesoporous WO3 thin film material.

[0057] (4) Place the ordered mesoporous WO3 thin film material in the middle of the tube furnace, weigh 1.0 g of sulfur powder into a ceramic boat, place it at the gas inlet end (so that the sulfur powder temperature is maintained at 150-200 ℃), heat the tube furnace to 400 ℃ at a heating rate of 10 ℃ / min, and keep it at 400 ℃ for 1.0 h. After cooling, the ordered mesoporous tungsten disulfide material is obtained. Example 4

[0058] (1) 0.05 g of the amphiphilic block copolymer polystyrene-polyethylene oxide (PS-) b Dissolve 0.2 g of phosphotungstic acid in 5.0 mL of pyridine and stir with a magnetic stirrer to obtain a transparent solution A; dissolve 0.2 g of phosphotungstic acid in 2 mL of deionized water and stir to obtain a homogeneous solution B; mix the above solutions A and B and stir for 1.0 h to obtain a light blue transparent colloidal solution C.

[0059] (2) Take 4 mL of solution C and spin-coat it onto a silicon wafer (2×2 cm). 2 The solvent was evaporated at room temperature for 6 hours, and then the silicon wafer was transferred to a 100°C oven to further evaporate the solvent and cure for 12 hours to obtain a silicon wafer containing a light blue composite film.

[0060] (3) The silicon wafer containing the light blue composite film was placed in a tube furnace and calcined at 500 °C for 1 h under an argon atmosphere, with a heating rate of 1 °C / min before 350 °C and 5 °C / min after 350 °C. The resulting sample was then calcined in air at 400 °C for 1.0 h (heating rate of 5 °C / min) to obtain a silicon wafer containing ordered mesoporous WO3 thin film material.

[0061] (4) Place the silicon wafer containing ordered mesoporous WO3 thin film material in the middle of the tube furnace, weigh 1.0 g of sulfur powder into a ceramic boat, place it at the gas inlet end (so that the temperature of the sulfur powder is maintained at 150-200 ℃), heat the tube furnace to 450 ℃ at a heating rate of 10 ℃ / min, and keep it at 450 ℃ for 1.0 h. After cooling, the ordered mesoporous tungsten disulfide material is obtained. Example 5

[0062] The ordered mesoporous tungsten disulfide thin film material obtained in Example 1 was used to fabricate a semiconductor gas sensor, and its comprehensive gas sensing performance was tested. Specifically, the ordered mesoporous tungsten disulfide thin film material was attached to a Pt electrode and placed in a 1.8L test chamber. A Xiaoyu Electronics M2.0 gas-sensitive testing instrument automatically recorded the real-time changes in the resistance of the ordered mesoporous tungsten disulfide thin film material. At the start of the test, several concentrations (5 ppm, 10 ppm, 20 ppm, 50 ppm, 100 ppm, 200 ppm, 500 ppm) of dry NO2 gas were injected using a syringe. The resistance began to change. Once the resistance stabilized, the cap was opened, exposing the ordered mesoporous tungsten disulfide thin film material to air, and the resistance returned to its initial value. In this test, the sensitivity (responsivity) of the ordered mesoporous tungsten disulfide thin film material was defined as S = (R0 / R0)0. a -R g ) / R a , where R a and R g These are the resistivity values ​​of the ordered mesoporous tungsten disulfide thin film material in air and the test gas, respectively. The response-recovery time is defined as the time required for 90% of the resistance change to complete. The results are as follows: Figure 5 As shown.

[0063] Figure 5The figures show the room temperature NO2 gas sensing performance test results of the ordered mesoporous tungsten disulfide material prepared in Example 1. (a) shows the dynamic response-recovery curves of the ordered mesoporous tungsten disulfide material obtained in Example 1 at room temperature to different concentrations (5-500 ppm) of NO2. (b) shows the response values ​​of the ordered mesoporous tungsten disulfide material obtained in Example 1 at room temperature to different concentrations (5-500 ppm) of NO2. (c) is the response-recovery time diagram of the ordered mesoporous tungsten disulfide material obtained in Example 1 to 50 ppm NO2 at room temperature; (d) is the cyclic response-recovery test diagram of the ordered mesoporous tungsten disulfide material obtained in Example 1 to 50 ppm NO2 at room temperature; (e) is the response value diagram of the ordered mesoporous tungsten disulfide material obtained in Example 1 to 50 ppm of different types of gases (nitric oxide, nitrogen dioxide, carbon monoxide, hydrogen, methanol, ethanol, acetone, formaldehyde, methane, benzene, etc.) at room temperature; (f) is a comparison diagram of the room temperature NO2 gas sensing performance of the ordered mesoporous tungsten disulfide material obtained in Example 1 and the materials reported in the literature (WS2@MTCNFs, Au@MoS2, WS2 / WO3 heterojunction, WS2 thin film, MoS2 sheet, planar MoS2, WSe2, etc.).

[0064] Depend on Figure 5 As can be seen from (a)-(b), the ordered mesoporous tungsten disulfide material prepared in Example 1 gradually increases in sensitivity and tends to saturate as the NO2 concentration increases, with a sensitivity of S=60% for 50 ppm NO2.

[0065] Depend on Figure 5 As can be seen from (c) and (d), the ordered mesoporous tungsten disulfide material sensor prepared in Example 1 has response-recovery times of 27 s and 130 s for 50 ppm NO2, respectively, and the sensor also has good cyclic stability.

[0066] Depend on Figure 5 (e) As can be seen, the ordered mesoporous tungsten disulfide material sensor prepared in Example 1 has a sensitivity of S=60% to 50 ppm NO2, and its sensitivity to other gases is less than 5%, indicating that the sensor has high selectivity to NO2.

[0067] Figure 5(f) Compares the room-temperature NO2 gas-sensing performance of the ordered mesoporous tungsten disulfide material (mesoporous WS2) obtained in Example 1 with references in Sensors and Actuators: B. Chemical 382 (2023) 133505 (Au@MoS2), Sensors & Actuators: B. Chemical 300 (2019) 127013 (WSe2), ACS Sens. 2018, 3, 998−1004; ACS Sens. 2018, 3, 998−1004 (MoS2 thin film), ACS Nano 2015, 9, 9, 9314–9321 (MoS2 sheet), Sensors and Actuators: B. Chemical 371 (2022) 132523 (MoS2 (light conditions)), RSCAdv., 2023, 13, The values ​​reported in this figure are compared with those in WS2 films (14841–14848), J. Mater. Chem. A, 2017, 5, 8725–8732 (WS2@MTCNFs), ACS Appl. Nano Mater. 2021, 4, 1626−1634 (WS2 / WO3 heterojunction), and ACS Sens. 2017, 2, 1744−1752 (planar MoS2). The horizontal axis represents NO2 concentration, and the vertical axis represents sensitivity. Figure 5 (f) It can be seen that the NO2 gas sensing performance of the ordered mesoporous WS2 prepared in Example 1 is significantly better than that of other existing transition metal chalcogenide materials.

Claims

1. An ordered mesoporous tungsten disulfide material, characterized in that, The ordered mesoporous tungsten disulfide material is prepared using an amphiphilic block copolymer as a template agent and a polyoxometalate as a precursor. The hydrophilic segments of the amphiphilic block copolymer and the polyoxometalate self-assemble in a solvent through electrostatic attraction, causing the metal precursor to adsorb onto the template agent to form a microphase structure, resulting in an ordered mesoporous structure. The hydrophobic segments of the amphiphilic block copolymer aggregate in the solvent, forming spherical micelles with hydrophobic segments as the core and hydrophilic segments as the shell. The material is obtained by calcining under an Ar atmosphere to remove the template agent and decompose the polyoxometalate, followed by calcination in air to remove carbon, and then sulfidation. The polyoxometalate is one or more of ammonium metatungstate, ammonium phosphotungstate, silicotungstic acid, and phosphotungstic acid. The amphiphilic block copolymer is polystyrene-polyethylene oxide, polyethylene oxide-polymethyl methacrylate, or polystyrene-poly4-vinylpyridine. The pore size of the ordered mesoporous tungsten disulfide material is 10-50 nm, and the thickness of the walls between the ordered mesopores is 2-10 nm. nm, the preparation method of the ordered mesoporous tungsten disulfide material includes the following steps: (1) Dissolve the amphiphilic block copolymer in an organic solvent and stir until homogeneous to obtain solution A; dissolve the polyoxometalate in deionized water and stir until homogeneous to obtain homogeneous solution B; mix solution A and solution B and stir until homogeneous to obtain homogeneous solution C; the organic solvent is one of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, and pyridine; the mass ratio of the amphiphilic block copolymer to the polyoxometalate is 1:3-6; and the volume ratio of the deionized water to the organic solvent is 1:5-50. (2) Spin-coat homogeneous solution C onto the substrate, evaporate at room temperature, and dry to obtain a substrate carrying the composite film; (3) The substrate carrying the composite film is calcined in an argon atmosphere and then calcined in an air atmosphere to obtain an ordered mesoporous WO3 film material. The calcination in the argon atmosphere is to first heat the material to 350 ℃ at a heating rate of 1-3 ℃ / min, and then heat it to 400-500 ℃ at a heating rate of 5-10 ℃ / min, and hold it for 1-3 h. The calcination in the air atmosphere is to heat the material to 350 ℃-400 ℃ at a heating rate of 5-10 ℃ / min, and calcinate it in the air at 350-400 ℃ for 1-3 h. (4) The ordered mesoporous WO3 film material is placed in a tube furnace for sulfurization to obtain the ordered mesoporous tungsten disulfide material. The sulfurization is to heat the material to 350-450 ℃ at a heating rate of 5-10 ℃ / min and hold it for 0.5-1.0 h.

2. The method for preparing the ordered mesoporous tungsten disulfide material according to claim 1, characterized in that, Includes the following steps: (1) Dissolve the amphiphilic block copolymer in an organic solvent and stir until homogeneous to obtain solution A; The polyoxometalate is dissolved in deionized water and stirred until homogeneous to obtain homogeneous solution B. Solution A is mixed with solution B and stirred until homogeneous to obtain homogeneous solution C. The organic solvent is one of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, and pyridine. The mass ratio of the amphiphilic block copolymer to the polyoxometalate is 1:3-6, and the volume ratio of the deionized water to the organic solvent is 1:5-50. (2) Spin-coat homogeneous solution C onto the substrate, evaporate at room temperature, and dry to obtain a substrate carrying the composite film; (3) The substrate carrying the composite film is calcined in an argon atmosphere and then calcined in an air atmosphere to obtain an ordered mesoporous WO3 film material. The calcination in the argon atmosphere is to first heat the material to 350 ℃ at a heating rate of 1-3 ℃ / min, and then heat it to 400-500 ℃ at a heating rate of 5-10 ℃ / min, and hold it at that temperature for 1-3 h. The calcination in the air atmosphere is to heat the material to 350 ℃-400 ℃ at a heating rate of 5-10 ℃ / min, and calcin it in the air at 350-400 ℃ for 1-3 h. (4) The ordered mesoporous WO3 thin film material is placed in a tube furnace for sulfidation to obtain the ordered mesoporous tungsten disulfide material. The sulfidation is carried out by heating the material to 350-450 ℃ at a heating rate of 5-10 ℃ / min and holding it at that temperature for 0.5-1.0 h.

3. The preparation method according to claim 2, characterized in that, In step (1), the hydrophilic segment of the amphiphilic block copolymer has a molecular weight of 2500-7500 g / mol and the hydrophobic segment has a molecular weight of 2500-37500 g / mol.

4. The preparation method according to claim 2, characterized in that, In step (2), the substrate is a silicon wafer, a glass plate or a petri dish, the evaporation time at room temperature is 6-12 h, the drying temperature is 100-150 ℃, and the drying time is 12-24 h.

5. The application of the ordered mesoporous tungsten disulfide material of claim 1 in the preparation of gas sensors, photocatalysis, and photoelectric detection.

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