BiVO4 / tourmaline composite material with negative oxygen ion release function and preparation method and application thereof

Abstract

The application discloses a BiVO4 / tourmaline composite material with a negative oxygen ion releasing function and a preparation method and application thereof, relates to the technical field of functional materials, and solves the problems of weak negative oxygen ion releasing capacity and environmental influence of traditional tourmaline materials. The BiVO4 / tourmaline composite material preparation method is that a bismuth source and a vanadium source are added into dimethyl sulfoxide to prepare a mixed solution A; tourmaline powder and glucose are added into water to prepare a mixed solution B; the mixed solution A is added into the mixed solution B to prepare a mixed solution C; the mixed solution C is subjected to freeze drying, grinding, and a mixture D is obtained; the mixture D is calcined at high temperature under an air atmosphere, naturally cooled to room temperature, and ground, so that the composite material is obtained. The BiVO4 / tourmaline composite material prepared by the application has high negative oxygen ion generation efficiency and environmental adaptability, and can maintain a high negative ion release amount in a complex environment such as weak light and low humidity.

Description

Technical Field

[0001] This invention relates to the field of functional materials technology, and in particular to a BiVO4 / tourmaline composite material with negative oxygen ion release function, its preparation method and application. Background Technology

[0002] In contemporary society, where sub-health issues are increasingly prominent, negative oxygen ions have become a hot research area at the intersection of medicine and environmental science due to their multiple roles in physiological regulation. Medical research shows that negative oxygen ions can relieve stress and anxiety by stimulating the parasympathetic nervous system and lowering cortisol levels. Simultaneously, their negative charge can improve alveolar gas exchange efficiency and promote blood circulation, showing significant adjunctive therapeutic effects for patients with chronic respiratory diseases such as asthma and chronic bronchitis. Furthermore, negative oxygen ions can enhance the body's immunity by increasing leukocyte activity and antioxidant capacity, creating more favorable living and learning spaces for the elderly, children, and people under high pressure. Researching materials that can stably release negative oxygen ions can not only provide precise health environment support for special places such as hospitals, nursing homes, and schools, but also reduce the burden on public healthcare through large-scale application, promoting the implementation of the "preventive medicine" concept in daily life. From a public health perspective, the development of such materials has significant social value, and their promotion is expected to become a strategic measure to improve the overall health level of the population and enhance the quality of life.

[0003] In the crystal structure of tourmaline, the asymmetric arrangement of silicon-oxygen rings and metal cations results in a permanent spontaneous polarization capability along the c-axis. This polarization phenomenon originates from the shift of positive and negative charge centers within the crystal, forming a stable surface electrostatic field (with an intensity of up to 10). 4 -10 7 (V / m) can directly act on water vapor molecules in the air without the need for external energy. Under the influence of the electric field, water molecules are polarized and undergo electrolysis, decomposing into hydrogen ions (H+). + ) and hydroxide ions (OH) - The latter further combines with oxygen to generate negative oxygen ion clusters (such as O2). - ·(H2O) n This process relies not only on the built-in electric field of tourmaline but is also closely related to the piezoelectric and pyroelectric effects—when the ambient temperature changes or is subjected to mechanical vibration, the polarization intensity of tourmaline further increases, thereby significantly improving the release efficiency of negative oxygen ions. Although tourmaline is an ideal natural source of negative ions, its release efficiency is limited by factors such as air humidity, small specific surface area, easy aggregation, surface deactivation, and short ion lifetime, making it difficult to independently meet the needs of high-efficiency purification. It often needs to be combined with other technologies to enhance its performance.

[0004] Bismuth vanadate (BiVO4) is a semiconductor material with a band gap of approximately 2.4 eV, exhibiting excellent visible light photocatalytic properties. Due to its narrow band gap, this material can effectively absorb visible light and generate photogenerated carriers. With the rise of semiconductor-mineral composite strategies, combining bismuth vanadate (BiVO4) with tourmaline to construct heterostructure systems represents a highly promising synergistic enhancement pathway.

[0005] Therefore, how to combine bismuth vanadate (BiVO4) with tourmaline to prepare a composite material that has a stronger negative oxygen ion release function than tourmaline alone and is less susceptible to environmental impact is a problem that needs to be solved. Summary of the Invention

[0006] To address the above shortcomings, this invention provides a BiVO4 / tourmaline composite material with negative oxygen ion release function, its preparation method, and its application, solving the problems of weak negative oxygen ion release capacity and susceptibility to environmental influences in traditional tourmaline materials. The specific technical solution is as follows: A method for preparing a BiVO4 / tourmaline composite material with negative oxygen ion release function includes the following steps: (1) Add bismuth source and vanadium source to dimethyl sulfoxide and sonicate for 30-60 min to obtain mixture A; add tourmaline powder and glucose to water and stir for 30-60 min, and add 0.5 mol / L dilute nitric acid solution dropwise to adjust the pH to 1-2 to obtain mixture B; slowly add mixture A dropwise to mixture B and stir for 10-25 min to obtain mixture C; (2) Freeze-dry the mixture C to obtain a precursor, and grind the precursor in a grinding container for 30-180 min to obtain mixture D; (3) The mixture D is transferred to a high-temperature resistant ceramic boat, placed in a muffle furnace, and calcined at 500-800℃ for 1-4 h in an air atmosphere to obtain product E; (4) The product E is naturally cooled to room temperature in the furnace, taken out, and ground for 15-60 min to obtain product F. Product F is the BiVO4 / tourmaline composite material with negative oxygen ion release function.

[0007] Preferably, in step (1), the bismuth source is bismuth nitrate pentahydrate (Bi(NO3)3·5H2O); the vanadium source is vanadium acetylacetonate; and the molar ratio of bismuth to vanadium is (0.5-2):1.

[0008] Preferably, in step (1), the mass-to-volume ratio of the mixture of bismuth source and vanadium source to dimethyl sulfoxide is 1:(2-5 mL).

[0009] Preferably, in step (1), the tourmaline powder is black tourmaline powder; the amount of black tourmaline powder added is 1-4 times the mass of the bismuth source.

[0010] Preferably, in step (1), the amount of glucose added is 2%-8% of the total mass of bismuth source, vanadium source and tourmaline powder.

[0011] Preferably, in step (1), the mass-to-volume ratio of the mixture of tourmaline powder and glucose to water is 1:(20-50 mL).

[0012] Preferably, in step (2), the freeze-drying temperature is -40℃ and the time is 12-18 h; the precursor grinding time is 30-180 min.

[0013] The present invention also provides a BiVO4 / tourmaline composite material prepared by the preparation method described above.

[0014] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention creates a composite material by combining tourmaline and bismuth vanadate (BiVO4). In this material, the photogenerated electrons generated by BiVO4 under light can form a synergistic effect with the spontaneous polarization electric field of tourmaline, significantly enhancing the interfacial electric field strength, promoting the directional polarization and ionization of water molecules, and greatly improving the generation rate and steady-state concentration of negative oxygen ions in the composite material. This breaks through the technical bottleneck of weak release capacity and strong environmental dependence of single tourmaline materials.

[0015] 2. This invention incorporates glucose during the preparation process, achieving multiple functional regulation through a one-step high-temperature treatment: Glucose partially carbonizes at high temperatures to form a carbonaceous interlayer or mesoporous structure, enhancing the material's adsorption capacity for water molecules and improving water molecule utilization in low-humidity environments. The gas released during its decomposition helps form a porous structure, further increasing the specific surface area and enhancing interfacial reactivity. Simultaneously, the residual carbon layer acts as an electron transport medium, promoting the migration of photogenerated electrons from BiVO4 to the tourmaline interface, improving charge separation efficiency and thus increasing the generation efficiency of negative oxygen ions. This synergistic mechanism not only significantly improves the negative ion release stability of the composite material under complex environments such as weak light and low humidity, but also endows it with good structural stability and long service life, breaking through the technical bottleneck of traditional tourmaline materials in terms of environmental adaptability.

[0016] 3. The introduction of bismuth vanadate in this invention can effectively improve the dispersibility of tourmaline powder and inhibit its agglomeration. At the same time, its layered structure and high specific surface area provide abundant active sites for the reaction, extend the service life of the material, and endow the composite system with the function of self-cleaning and synergistic degradation of pollutants under light conditions.

[0017] 4. This invention uses a solid-state method to prepare BiVO4 / tourmaline composite materials. It only requires mixing the required raw materials and then sintering them through a simple solid-state method. The entire preparation process is simple, the conditions are easy to control, the production cost is low, and it is easy to industrialize. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 X-ray diffraction analysis pattern of the BiVO4 / tourmaline composite material prepared in Example 2; Figure 2 This is a scanning electron microscope image of the BiVO4 / tourmaline composite material prepared in Example 2 at 5 μm. Figure 3 Infrared spectrum of the BiVO4 / tourmaline composite material prepared in Example 2; Figure 4 The graph shows a comparison of the negative ion release performance of the BiVO4 / tourmaline composite material prepared in Example 2, the BiVO4 / tourmaline composite material prepared in Comparative Example 1, the BiVO4 material alone, and the tourmaline material alone. Detailed Implementation

[0020] The specific embodiments of the present invention are described in detail below, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments. Unless otherwise defined, all technical terms used below have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing specific embodiments only and are not intended to limit the scope of protection of the present invention. Unless otherwise specifically stated, all raw materials, reagents, instruments, and equipment used in the present invention are commercially available or can be prepared by existing methods.

[0021] Example 1 This embodiment describes a method for preparing a BiVO4 / tourmaline composite material with negative oxygen ion release function, comprising the following steps: (1) According to the molar ratio of bismuth (Bi) and vanadium (V) (n(Bi): n(V) = 0.5:1), the amount of black tourmaline added is 1 times the mass of the added bismuth nitrate pentahydrate, and the amount of glucose added is 2% of the total mass of bismuth source, vanadium source and tourmaline powder. Weigh 1 g of bismuth nitrate pentahydrate (Bi(NO3)3·5H2O) and vanadium acetylacetonate and add them to 2 mL of dimethyl sulfoxide and sonicate for 30 min to obtain mixture A; weigh the corresponding mass of black tourmaline powder and glucose and add them to 20 mL of water and stir for 30 min. Add 0.5 mol / L dilute nitric acid solution to adjust the pH to 1. The amount added is about 2 mL to obtain mixture B; slowly add solution A to mixture B and stir for 10 min to obtain mixture C. (2) The mixture C obtained in step (1) is freeze-dried at -40 ℃ for 12 h to obtain the precursor. The precursor is placed in a grinding container and ground for 30 min until a fine powder and uniformly mixed precursor mixture D is formed. (3) The precursor mixture D obtained in step (2) is transferred to a high-temperature resistant ceramic boat, placed in a muffle furnace, and calcined at 500 °C for 1 h in an air atmosphere to obtain calcined product E; (4) After calcination, product E is naturally cooled to room temperature in the furnace, taken out and ground thoroughly for 15 min to obtain the final target product bismuth vanadate / tourmaline composite powder F.

[0022] The negative ion release of the composite material prepared in this embodiment was tested to be 520 ions / cm³.

[0023] Example 2 This embodiment describes a method for preparing a BiVO4 / tourmaline composite material with negative oxygen ion release function, comprising the following steps: (1) According to the molar ratio of bismuth (Bi) and vanadium (V) (n(Bi): n(V) = 1:1), the amount of black tourmaline added is twice the mass of the added bismuth nitrate pentahydrate, and the amount of glucose added is 4% of the total mass of bismuth source, vanadium source and tourmaline powder. Weigh 1 g of bismuth nitrate pentahydrate (Bi(NO3)3·5H2O) and vanadium acetylacetonate and add them to 3 ml of dimethyl sulfoxide and sonicate for 40 min to obtain mixture A; weigh the corresponding mass of black tourmaline powder and glucose and add them to 30 ml of water and stir for 40 min. Add 0.5 mol / L dilute nitric acid solution to adjust the pH to 1. The amount added is about 3 mL to obtain mixture B; slowly add solution A to mixture B and stir for 15 min to obtain mixture C. (2) The mixture C obtained in step (1) is freeze-dried at -40 ℃ for 14 h to obtain the precursor. The precursor is placed in a grinding container and ground for 60 min until a fine powder and uniformly mixed precursor mixture D is formed. (3) The precursor mixture D obtained in step (2) is transferred to a high-temperature resistant ceramic boat, placed in a muffle furnace, and calcined at 600 °C for 2 h in an air atmosphere to obtain calcined product E; (4) After calcination, product E is naturally cooled to room temperature in the furnace, taken out and ground thoroughly for 30 min to obtain the final target product bismuth vanadate / tourmaline composite powder F.

[0024] The X-ray diffraction pattern of the BiVO4 / tourmaline composite material prepared in this embodiment is shown in the figure below. Figure 1 As shown in the figure, the horizontal axis represents the 2θ angle and the vertical axis represents the diffraction peak intensity. The figure shows that the composite material exhibits characteristic diffraction peaks of both BiVO4 and tourmaline, with no impurity phase peaks, indicating that the two were successfully composited.

[0025] The scanning electron microscope (SEM) image of the BiVO4 / tourmaline composite material prepared in this embodiment at 5 μm is shown below. Figure 2 As shown in the figure, BiVO4 appears as irregular granular or flaky morphology with a particle size of about 0.5–2 μm, and is relatively uniformly dispersed and attached to the surface and surrounding of tourmaline particles.

[0026] The infrared spectrum of the BiVO4 / tourmaline composite material prepared in this embodiment is as follows: Figure 3 As shown in the figure, the infrared spectrum of this composite material is as follows: 700-900 cm⁻¹ -1 and 400-600 cm -1 The peaks correspond to the VOV and Bi-O vibrations of bismuth vanadate, respectively, in the range of 900-1200 cm⁻¹. -1 The peak corresponds to the Si-O-Si vibration in tourmaline. If it is in the 1000-1100 cm⁻¹ range... -1 The appearance of new peaks indicates the formation of interfacial bonds such as VO-Si, which enhances the interaction between the two phases. (3000-3600 cm⁻¹) -1 The presence of OH peaks indicates that the material surface is rich in hydroxyl groups. These structures collectively enhance the material's spontaneous polarization and photocatalytic charge separation efficiency, thereby synergistically strengthening its negative ion release performance.

[0027] Example 3 This embodiment describes a method for preparing a BiVO4 / tourmaline composite material with negative oxygen ion release function, comprising the following steps: (1) According to the molar ratio of bismuth (Bi) and vanadium (V) (n(Bi): n(V) = 1.5:1), the amount of black tourmaline added is 3 times the mass of the added bismuth pentahydrate nitrate, and the amount of glucose added is 6% of the total mass of bismuth source, vanadium source and tourmaline powder. Weigh 1 g of bismuth pentahydrate nitrate (Bi(NO3)3·5H2O) and acetylacetone vanadium oxide and add them to 4 ml of dimethyl sulfoxide and sonicate for 50 min to obtain mixture A; weigh the corresponding mass of black tourmaline powder and glucose and add them to 40 ml of water and stir for 50 min. Add 0.5 mol / L dilute nitric acid solution to adjust the pH to 2. The amount added is about 0.8 mL to obtain mixture B; slowly add solution A to mixture B and stir for 20 min to obtain mixture C. (2) The mixture C obtained in step (1) was freeze-dried at -40 °C for 16 h to obtain the precursor. The precursor was placed in a grinding container and ground for 120 min until a fine powder and uniformly mixed precursor mixture D was formed. (3) The precursor mixture D obtained in step (2) is transferred to a high-temperature resistant ceramic boat, placed in a muffle furnace, and calcined at 700 °C for 3 h in an air atmosphere to obtain calcined product E; (4) After calcination, product E is cooled to room temperature naturally with the furnace, then taken out and ground thoroughly for 45 min to obtain the final target product bismuth vanadate / tourmaline composite powder F.

[0028] The negative ion release of the composite material prepared in this embodiment was tested to be 530 ions / cm³.

[0029] Example 4 This embodiment describes a method for preparing a BiVO4 / tourmaline composite material with negative oxygen ion release function, comprising the following steps: (1) According to the molar ratio of bismuth (Bi) and vanadium (V) (n(Bi): n(V) = 2:1), the amount of black tourmaline added is 4 times the mass of the added bismuth nitrate pentahydrate, and the amount of glucose added is 8% of the total mass of bismuth source, vanadium source and tourmaline powder. Weigh 1 g of bismuth nitrate pentahydrate (Bi(NO3)3·5H2O) and vanadium acetylacetonate and add them to 5 ml of dimethyl sulfoxide and sonicate for 60 min to obtain mixture A; weigh the corresponding mass of black tourmaline powder and glucose and add them to 50 ml of water and stir for 60 min. Add 0.5 mol / L dilute nitric acid solution dropwise to adjust the pH to 2. The amount added is about 1.0 mL to obtain mixture B; slowly add solution A to mixture B and stir for 25 min to obtain mixture C. (2) The mixture C obtained in step (1) is freeze-dried at -40 ℃ for 18 h to obtain the precursor. The precursor is placed in a grinding container and ground for 180 min until a fine powder and uniformly mixed precursor mixture D is formed. (3) The precursor mixture D obtained in step (2) is transferred to a high-temperature resistant ceramic boat, placed in a muffle furnace, and calcined at 800°C for 4 h in an air atmosphere to obtain calcined product E. (4) After calcination, product E is naturally cooled to room temperature in the furnace, taken out and ground thoroughly for 60 min to obtain the final target product bismuth vanadate / tourmaline composite powder F.

[0030] The negative ion release of the composite material prepared in this embodiment was tested to be 560 ions / cm³.

[0031] Comparative Example 1: In this comparative example, no glucose was added during the preparation of the BiVO4 / tourmaline composite material, and the other preparation steps were the same as in Example 2.

[0032] The negative ion release rates of the composite material from Example 2, the composite material from Comparative Example 1, the BiVO4 material alone, and the tourmaline material alone were measured separately, with the negative ion release rate in the environment used as a reference. The results are as follows: Figure 4 As shown in the figure, the negative ion release of the composite material in Example 2 is 620 ions / cm³; the negative ion release of the composite material in Comparative Example 1 is 490 ions / cm³; the negative ion release of BiVO4 material alone is 220 ions / cm³; and the negative ion release of tourmaline material alone is 380 ions / cm³. It is evident that the negative ion release performance of tourmaline composited with bismuth vanadate in this invention is significantly improved compared to pure tourmaline, and the addition of glucose further enhances the negative ion release performance.

[0033] To illustrate the effectiveness of the material in low-humidity environments, the applicant tested the negative oxygen ion release of each material under normal humidity conditions (50% relative humidity) and low humidity conditions (30% relative humidity), respectively. The results showed: Under normal humidity conditions of 50% relative humidity, the negative oxygen ion release of pure tourmaline is 310–380 ions / cm³, while the BiVO4 / tourmaline-glucose composite material prepared by the present invention (Examples 1-3) can reach 580–630 ions / cm³. When the relative humidity drops to a low humidity environment of 30%, the release of pure tourmaline drops sharply to 150–180 ions / cm³, with a retention rate of only about 45%–50%, showing significant attenuation. However, the composite material of the present invention (Examples 1-3) can still maintain 400–450 ions / cm³, with a retention rate of 60%–65%, which is far superior to pure tourmaline.

[0034] The foregoing description of specific exemplary embodiments of the invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. The scope of the invention is intended to be defined by the claims and their equivalents.

Claims

1. A method for preparing a BiVO4 / tourmaline composite material with negative oxygen ion release function, characterized in that, Includes the following steps: (1) Add bismuth source and vanadium source to dimethyl sulfoxide and sonicate to obtain mixture A; add tourmaline powder and glucose to water and stir, and add dilute nitric acid to adjust pH to 1–2 to obtain mixture B; The mixture A is slowly added dropwise to the mixture B, and the mixture is stirred to obtain mixture C; (2) Freeze-dry the mixture C to obtain a precursor, and grind the precursor to obtain a mixture D; (3) The mixture D is calcined in air at 500-800 °C for 1-4 h to obtain product E; (4) The product E is naturally cooled to room temperature in the furnace, taken out, and ground for 15-60 min to obtain product F. Product F is the BiVO4 / tourmaline composite material with negative oxygen ion release function.

2. The preparation method of the BiVO4 / tourmaline composite material with negative oxygen ion release function according to claim 1, characterized in that, In step (1), the bismuth source is bismuth nitrate pentahydrate; the vanadium source is vanadium acetylacetonate; and the molar ratio of bismuth to vanadium is (0.5-2):

1.

3. The method for preparing a BiVO4 / tourmaline composite material with negative oxygen ion release function according to claim 1, characterized in that, In step (1), the mass-to-volume ratio of the mixture of bismuth source and vanadium source to dimethyl sulfoxide is 1:(2-5 mL).

4. The preparation method of the BiVO4 / tourmaline composite material with negative oxygen ion release function according to claim 1, characterized in that, In step (1), the tourmaline powder is black tourmaline powder; the amount of black tourmaline powder added is 1-4 times the mass of the bismuth source.

5. The preparation method of a BiVO4 / tourmaline composite material with negative oxygen ion release function according to claim 1, characterized in that, In step (1), the amount of glucose added is 2%-8% of the total mass of bismuth source, vanadium source and tourmaline powder.

6. The preparation method of the BiVO4 / tourmaline composite material with negative oxygen ion release function according to claim 1, characterized in that, In step (1), the mass-to-volume ratio of the mixture of tourmaline powder and glucose to water is 1:(20-50 mL).

7. The preparation method of a BiVO4 / tourmaline composite material with negative oxygen ion release function according to claim 1, characterized in that, In step (2), the freeze-drying temperature is -40 ℃ and the time is 12-18 h; the precursor grinding time is 30-180 min.

8. A BiVO4 / tourmaline composite material prepared by the preparation method according to any one of claims 1-7.

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