Preparation method and application of acanthosphere-shaped S-doped O vacancy bismuth oxide material
By preparing spherical S-doped O-vacancy bismuth oxide materials, the problems of easy agglomeration and few active sites of Bi2O3 nanomaterials were solved, and the functional performance of the materials was improved, especially the high sensitivity to NO2 at room temperature.
Patent Information
- Application Number
- CN202510928276.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-07
- Publication Date
- 2025-09-19
AI Technical Summary
Existing Bi2O3 nanomaterials are prone to agglomeration and have few active sites, resulting in reduced functional properties.
By preparing thorny S-doped O-vacancy bismuth oxide (S-Bi2O3-x) materials, Bi2S3 was sintered at high temperature to form a hierarchical structure and introduce O vacancy defects to avoid nanowire agglomeration and increase the active surface and reaction sites.
The functional performance of the material is improved, especially its sensitivity to NO2 at room temperature, making it suitable for use as a gas-sensitive material in sensors.
Smart Images
Figure CN120664585A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of functional materials, and in particular relates to a preparation method and application of a spherical S-doped O-vacancy bismuth oxide material. Background Art
[0002] Bismuth oxide (Bi2O3) semiconductor materials have unique electronic structures and good light absorption properties, which make them widely used in photocatalysis, sensors, energy storage and other fields. At present, Bi2O3 nanomaterials have been successfully synthesized through various methods such as physical deposition and chemical synthesis, such as Bi2O3 nanorods, nanowires, nanospheres and nanosheets. Since low-dimensional Bi2O3 nanomaterials are easy to agglomerate, the exposed active surface and material utilization rate are significantly reduced, resulting in the failure to effectively improve the functional properties. In addition, due to the limitations of its own structure, Bi2O3 semiconductor materials lead to rapid recombination of electron-hole pairs, a large reduction in the number of surface active sites, and further reduce the functional properties of the material. In order to solve the above-mentioned problems of Bi2O3 structure and itself, the present invention synthesized spherical S-doped O vacancy bismuth oxide (S-Bi2O 3-x The spiny sphere-like hierarchical structure effectively solves the agglomeration problem of low-dimensional Bi2O3 nanowires and maintains a stable structure. O vacancy defects provide abundant surface active sites, addressing the problem of a lack of surface active sites. The spiny sphere-like hierarchical structure and the abundant active sites provided by O vacancy defects synergistically enhance the functional properties of Bi2O3 materials. Summary of the Invention
[0003] The purpose of the present invention is to solve the problems of agglomeration, few active sites and reduced functional properties of Bi2O3 nanomaterials prepared by the prior art, and to provide a preparation method and application of spherical S-doped O-vacancy bismuth oxide materials.
[0004] A method for preparing a spherical S-doped O-vacancy bismuth oxide material is specifically completed by the following steps:
[0005] 1. Prepare the reaction solution:
[0006] adding bismuth nitrate and thiourea into deionized water and stirring magnetically to obtain a reaction solution;
[0007] 2. Hydrothermal reaction:
[0008] The reaction solution is transferred to a reactor, and then subjected to hydrothermal reaction at 140°C to 160°C for a period of time to obtain a reaction product;
[0009] 3. Centrifugal cleaning:
[0010] The reaction product is centrifuged and washed, and the obtained precipitate is vacuum dried to obtain Bi2S3 material;
[0011] 4. High temperature sintering:
[0012] The Bi2S3 material is transferred to a high-temperature furnace, then heated from room temperature to 440°C~460°C in an air atmosphere, kept warm for a period of time, and finally naturally cooled to room temperature to obtain a thorny spherical S-doped O-vacancy bismuth oxide material.
[0013] A thorny ball-shaped S-doped O-vacancy bismuth oxide material is used as a gas-sensing material.
[0014] Principle of the present invention:
[0015] The present invention prepares spherical S-doped O-vacancy bismuth oxide material (S-Bi2O) by high-temperature sintering Bi2S3. 3-x The material exhibits a hierarchical structure, effectively preventing 1D nanowire agglomeration and increasing the active surface area. Furthermore, sulfur doping generates a large number of oxygen vacancy defects, further increasing the number of reactive sites. The synthesis method is simple, low-pollution, and reproducible, making it suitable for industrial mass production. The spherical sulfur-doped oxygen-vacancy bismuth oxide material prepared by this invention exhibits excellent room-temperature NO2 sensitivity and can be used as a NO2-sensitive material.
[0016] Beneficial effects of the present invention:
[0017] The present invention synthesizes S-doped O vacancy bismuth oxide (S-Bi2O) by high temperature sintering method. 3-x ) materials to prepare S-Bi2O 3-x The material exhibits a thorny ball-like hierarchical structure and contains abundant O vacancy defects. This structural feature can effectively increase the reaction sites and active surface of the material, improve the functional performance of the material, and make the material have a broader application prospect.
[0018] The present invention is to prepare S-Bi2O 3-x The material was coated onto the interdigitated electrode to prepare a gas sensor. 3-x The sensor has excellent sensitivity to NO2 at room temperature.
[0019] Compared with the prior art, the present invention has the following significant features:
[0020] The present invention prepares a new type of thorn-shaped S-doped O vacancy S-Bi2O 3-x Material;
[0021] (1) S-Bi2O of the present invention 3-x The material exhibits a thorny ball-like hierarchical structure, effectively reducing nanowire agglomeration and exposing more active surface;
[0022] (2) S-Bi2O of the present invention 3-x The material contains abundant O vacancy defects and more reaction sites;
[0023] (3) S-Bi2O of the present invention 3-x The material exhibits room-temperature NO2 sensing properties. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Figure 1 S-Bi2O prepared in Example 1 3-x SEM images of materials;
[0025] Figure 2 S-Bi2O prepared in Example 1 3-x XPS spectrum of the material;
[0026] Figure 3 S-Bi2O prepared in Example 1 3-x EPR spectrum of the material;
[0027] Figure 4 Example 2 is the S-Bi2O prepared in Example 1. 3-x S-Bi2O prepared from materials 3-x NO2 sensitivity characteristic curve of the sensor at room temperature. DETAILED DESCRIPTION
[0028] Specific embodiment 1: This embodiment is a method for preparing a spherical S-doped O-vacancy bismuth oxide material, which is specifically completed by the following steps:
[0029] 1. Prepare the reaction solution:
[0030] adding bismuth nitrate and thiourea into deionized water and stirring magnetically to obtain a reaction solution;
[0031] 2. Hydrothermal reaction:
[0032] The reaction solution is transferred to a reactor, and then subjected to hydrothermal reaction at 140°C to 160°C for a period of time to obtain a reaction product;
[0033] 3. Centrifugal cleaning:
[0034] The reaction product is centrifuged and washed, and the obtained precipitate is vacuum dried to obtain Bi2S3 material;
[0035] 4. High temperature sintering:
[0036] The Bi2S3 material is transferred to a high-temperature furnace, then heated from room temperature to 440°C~460°C in an air atmosphere, kept warm for a period of time, and finally naturally cooled to room temperature to obtain a thorny spherical S-doped O-vacancy bismuth oxide material.
[0037] Specific embodiment 2: This embodiment differs from specific embodiment 1 in that the volume ratio of the bismuth nitrate mass to deionized water in step 1 is (1.0 g to 1.4 g): (150 mL to 170 mL). The other steps are the same as those in specific embodiment 1.
[0038] Specific embodiment 3: This embodiment differs from specific embodiments 1 or 2 in that the volume ratio of the thiourea mass to deionized water in step 1 is (1.0 g to 1.4 g): (150 mL to 170 mL). The other steps are the same as specific embodiments 1 or 2.
[0039] Specific embodiment 4: This embodiment differs from specific embodiments 1 to 3 in that the magnetic stirring time in step 1 is 1 to 2 hours. The other steps are the same as those in specific embodiments 1 to 3.
[0040] Specific embodiment 5: This embodiment differs from specific embodiments 1 to 4 in that the hydrothermal reaction time in step 2 is 8 to 12 hours. The other steps are the same as those in specific embodiments 1 to 4.
[0041] Specific Embodiment 6: This embodiment differs from Specific Embodiments 1 to 5 in that, in step 3, anhydrous ethanol and deionized water are sequentially used as cleaning agents, and the reaction product is centrifuged 2 to 4 times, respectively, at a centrifugal cleaning rate of 7000 to 9000 rpm. The vacuum drying temperature in step 3 is 70°C to 80°C, and the vacuum drying time is 12 to 16 hours. The other steps are the same as Specific Embodiments 1 to 5.
[0042] Specific embodiment 7: This embodiment differs from specific embodiments 1 to 6 in that the heating rate in step 4 is 5°C / min to 10°C / min and the holding time in step 4 is 1h to 3h. The other steps are the same as specific embodiments 1 to 6.
[0043] Specific embodiment eight: This embodiment uses a spiky ball-shaped S-doped O-vacancy bismuth oxide material as a gas-sensitive material. Other steps are the same as those of specific embodiments one to seven.
[0044] Specific embodiment 9: This embodiment differs from specific embodiments 1 to 8 in that a spherical S-doped O-vacancy bismuth oxide material is used as a gas-sensitive material to prepare a NO2 sensor, which is specifically completed by the following steps:
[0045] A spiky-ball-shaped, sulfur-doped, oxygen-vacancy bismuth oxide material is added to anhydrous ethanol and ultrasonically dispersed to obtain a gas-sensitive material solution. The gas-sensitive material solution is coated onto interdigitated electrodes and vacuum-dried to form a sensitive film, thereby obtaining a NO2 sensor based on the spiky-ball-shaped, sulfur-doped, oxygen-vacancy bismuth oxide material. The remaining steps are the same as those in Specific Embodiments 1 to 8.
[0046] Specific Embodiment 10: This embodiment differs from Specific Embodiments 1 to 9 in that the ultrasonic dispersion time is 10 to 20 minutes; the concentration of the gas-sensitive material solution is 1 mg / mL to 2 mg / mL; the vacuum drying temperature is 80°C and the vacuum drying time is 2 to 5 hours; and the thickness of the sensitive film is 4.5 μm to 5 μm. Other steps are the same as Specific Embodiments 1 to 9.
[0047] The following examples are used to verify the beneficial effects of the present invention:
[0048] Example 1: A method for preparing a spherical S-doped O-vacancy bismuth oxide material is specifically completed by the following steps:
[0049] 1. Prepare the reaction solution:
[0050] 1.2 g of bismuth nitrate and 1.2 g of thiourea were added to 160 mL of deionized water and magnetically stirred for 1 h to obtain a reaction solution;
[0051] 2. Hydrothermal reaction:
[0052] The reaction solution was transferred to a reactor and subjected to hydrothermal reaction at 160°C for 10 h to obtain a reaction product;
[0053] 3. Centrifugal cleaning:
[0054] The reaction product was centrifugally cleaned three times using anhydrous ethanol and deionized water as cleaning agents, respectively, at a rate of 8000 r / min. The obtained precipitate was then vacuum dried at a temperature of 80° C. for 12 h to obtain a Bi2S3 material.
[0055] 4. High temperature sintering:
[0056] 1.0 g of Bi2S3 material was transferred to a high-temperature furnace, and then heated from room temperature to 450°C at a heating rate of 5°C / min in an air atmosphere, kept at this temperature for 2 h, and finally cooled naturally to room temperature to obtain a spherical S-doped O-vacancy bismuth oxide material (S-Bi2O 3-x ).
[0057] (1) Scanning electron microscopy (SEM) was used to examine the S-Bi2O obtained in Example 1. 3-x The morphology of the material was observed, such as Figure 1As shown; S-Bi2O 3-x The material presents a thorny ball-like hierarchical structure assembled by nanowires. The diameter of the nanowires is about 300 nanometers. The formation of the thorny ball-like structure is conducive to the diffusion and adsorption of substances, thereby improving the functional properties of the material. Figure 2 S-Bi2O prepared in Example 1 3-x XPS spectrum of the material; S-Bi2O 3-x The presence of a small amount of S element in the material proves the doping of S element. Figure 3 S-Bi2O prepared in Example 1 3-x EPR spectrum of the material; an obvious signal appears at g=2.004, indicating that S-Bi2O 3-x There are abundant O vacancy defects in the material. Combined with the characterization structure, it is finally proved that the thorny spherical S doped O vacancy S-Bi2O 3-x Successful preparation of materials.
[0058] Example 2: S-Bi2O prepared using Example 1 3-x Material preparation S-Bi2O 3-x The sensor is completed in the following steps:
[0059] 20 mg of a spherical S-doped O-vacancy bismuth oxide material was added to 20 ml of anhydrous ethanol and ultrasonically dispersed for 10 min to obtain a gas-sensitive material solution. The gas-sensitive material solution was coated on an interdigital electrode and vacuum-dried at 80 ° C for 3 h to form a 5 μm thick sensitive film. A NO2 sensor based on the spherical S-doped O-vacancy bismuth oxide material (S-Bi2O 3-x sensor).
[0060] (2) The dynamic response performance test of the NO2 sensor prepared in Example 2 was carried out. Figure 4 As shown, from Figure 4 It can be seen that the NO2 sensor based on the spherical S-doped O vacancy bismuth oxide material can achieve (0.05~5)×10 -6 Volume fraction concentration NO2 room temperature test, for 1.0×10 -6 The sensitivity of NO2 volume fraction reaches 4.4, and the minimum detection concentration is 0.05×10 -6 Volume fraction of NO2. The test results show that S-Bi2O 3-x The sensor has the characteristics of high sensitivity, low detection limit and low power consumption, and has good application prospects.
Claims
1. A method for preparing a spherical S-doped O-vacancy bismuth oxide material, characterized in that The preparation method is specifically completed according to the following steps:
1. Prepare the reaction solution: adding bismuth nitrate and thiourea into deionized water and stirring magnetically to obtain a reaction solution; 2. Hydrothermal reaction: The reaction solution is transferred to a reactor, and then subjected to hydrothermal reaction at 140°C to 160°C for a period of time to obtain a reaction product; 3. Centrifugal cleaning: The reaction product is centrifuged and washed, and the obtained precipitate is vacuum dried to obtain Bi2S3 material; 4. High temperature sintering: The Bi2S3 material is transferred to a high-temperature furnace, then heated from room temperature to 440°C~460°C in an air atmosphere, kept warm for a period of time, and finally naturally cooled to room temperature to obtain a thorny spherical S-doped O-vacancy bismuth oxide material.
2. The method for preparing a spherical S-doped O-vacancy bismuth oxide material according to claim 1, characterized in that The volume ratio of the mass of bismuth nitrate described in step 1 to deionized water is (1.0g~1.4g):(150mL~170mL).
3. The method for preparing a spherical S-doped O-vacancy bismuth oxide material according to claim 1, characterized in that The volume ratio of the mass of thiourea described in step 1 to deionized water is (1.0g~1.4g):(150mL~170mL).
4. The method for preparing a spherical S-doped O-vacancy bismuth oxide material according to claim 1, characterized in that The magnetic stirring time in step 1 is 1 h to 2 h.
5. The method for preparing a spherical S-doped O-vacancy bismuth oxide material according to claim 1, characterized in that The hydrothermal reaction time in step 2 is 8h~12h.
6. The method for preparing a spherical S-doped O-vacancy bismuth oxide material according to claim 1, characterized in that In step three, anhydrous ethanol and deionized water are used as cleaning agents, and the reaction product is centrifuged and cleaned 2 to 4 times respectively, at a centrifugal cleaning rate of 7000 r / min to 9000 r / min; the vacuum drying temperature in step three is 70°C to 80°C, and the vacuum drying time is 12h to 16h.
7. The method for preparing a spherical S-doped O-vacancy bismuth oxide material according to claim 1, characterized in that The heating rate in step 4 is 5°C / min to 10°C / min; the insulation time in step 4 is 1h to 3h.
8. Use of a spherical S-doped O-vacancy bismuth oxide material prepared by the preparation method according to claim 1, characterized in that A thorny ball-shaped S-doped O-vacancy bismuth oxide material is used as a gas-sensing material.
9. The use of a spherical S-doped O-vacancy bismuth oxide material according to claim 8, characterized in that A spherical sulfur-doped oxygen vacancy bismuth oxide material is used as a gas-sensitive material to prepare a NO2 sensor, which is specifically completed by the following steps: A spiky-ball-shaped S-doped O-vacancy bismuth oxide material was added to anhydrous ethanol and ultrasonically dispersed to obtain a gas-sensitive material solution; the gas-sensitive material solution was coated on an interdigital electrode and vacuum-dried to form a sensitive film, thereby obtaining a NO2 sensor based on the spiky-ball-shaped S-doped O-vacancy bismuth oxide material.
10. The use of a spherical S-doped O-vacancy bismuth oxide material according to claim 9, characterized in that The ultrasonic dispersion time is 10 min to 20 min; the concentration of the gas-sensitive material solution is 1 mg / mL to 2 mg / mL; the vacuum drying temperature is 80° C., and the vacuum drying time is 2 h to 5 h; and the thickness of the sensitive film is 4.5 μm to 5 μm.