Silver vanadate photocatalytic material, preparation method thereof and illuminating lamp

Abstract

The invention discloses a silver vanadate photocatalytic material, a preparation method thereof and an illuminating lamp. The preparation method comprises the following steps: firstly, respectively dissolving NH4VO3 and AgNO3 in deionized water, uniformly mixing by magnetic stirring, adjusting the pH value of the solution, and then carrying out hydrothermal synthesis reaction to obtain the Ag3VO4 photocatalytic material. The Ag3VO4 photocatalytic material with controllable morphology, uniform particle size and good dispersity is prepared by adopting a synthesis strategy of a one-step hydrothermal method, the performance of the photocatalyst is optimized by regulating and controlling the pH value, the raw materials and the process are simple, the conditions are easy to control, the cost is low, the photocatalytic degradation rate of the catalyst to organic pollutants is high, and the method is suitable for industrial production. The stability of a crystal structure and catalytic activity can be kept under long-term illumination, and the functional application of a photocatalytic air purification technology can be realized by integrating with an illumination lamp.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor photocatalyst material preparation technology, and more specifically, relates to a silver vanadate photocatalyst material, its preparation, and lighting fixtures. Background Technology

[0002] In recent years, semiconductor photocatalysts have made significant progress in fields such as pollutant degradation. Silver vanadate (Ag3VO4), as a silver-based photocatalyst, possesses a unique band structure, a narrow band gap, and good visible light response, thus exhibiting excellent photocatalytic activity. However, the preparation method is a key factor affecting the performance of photocatalytic materials. Different preparation methods can lead to changes in the structure and properties of the material, resulting in differences in its photocatalytic performance. Currently reported traditional preparation methods for photocatalyst materials mainly include solid-phase methods and liquid-phase precipitation methods. Solid-phase methods involve incomplete high-temperature calcination, which easily produces impurities. These methods are energy-intensive, complex, and require intermediate grinding. The resulting products are prone to severe particle agglomeration, uncontrollable morphology, and few photocatalytic active sites, resulting in poor photocatalytic performance that fails to meet the requirements of high-efficiency photocatalysis. Liquid-phase precipitation methods tend to generate mixtures, making it difficult to control product purity. The precipitation process is rapid, resulting in irregular crystal growth, wide particle size distribution, and irregular blocky or large particle morphologies. Silver vanadate synthesized using this method has low photocatalytic activity and poor stability.

[0003] The hydrothermal method places the precursor in a high-pressure reactor and reacts it under a specific temperature environment. This allows for precise control of crystal nucleation and growth, resulting in products with high purity and crystallinity, multiple reactive sites, and easily controllable process conditions. Patent CN 106140159 B discloses an AgVO3 nanocatalyst prepared using a precipitation-assisted microwave hydrothermal method. Using V2O5 as the alum source, glucose as the surfactant, and AgNO3 as the silver source, the reaction is carried out in a microwave reactor after pH adjustment to obtain silver metavanadate AgVO3 photocatalyst. Under visible light irradiation, this catalyst achieves a 65% degradation rate of Rhodamine B within 200 minutes. However, this method requires the addition of the surfactant glucose to promote the dissolution of V2O5 in water, which is not conducive to recovery and reuse. The use of specialized microwave reactor equipment also significantly increases costs. Furthermore, the resulting silver metavanadate has poor absorption of visible light and a low photocatalytic degradation rate.

[0004] Patent CN 106191903 B provides a DC electrolytic synthesis method, the specific steps of which are as follows: (1) Using a silver sheet as the anode, an inert electrode as the cathode, an aqueous solution of sodium metavanadate and sodium nitrate as the anolyte, and a hydrochloric acid solution or sodium chloride solution as the cathode, silver vanadate with different structures and particle sizes is prepared in a double-chamber electrolytic cell with a cation membrane as the diaphragm by constant current electrolysis and by controlling the current density, electrolyte concentration and temperature; (2) After electrolysis, the product obtained on the anode is collected, washed, filtered and dried to obtain a silver vanadate photocatalyst; the obtained silver vanadate is spherical, rhomboid particles or dendritic structure. By precisely controlling multiple process parameters, the morphology and particle size of silver vanadate can be controlled. The silver vanadate material obtained by this method can achieve a degradation rate of nearly 100% for phenol within 160 min. However, the above method has a complex process operation, requires a lot of raw materials, and the electrolysis process has strict requirements on current density, electrolyte concentration and temperature conditions. Improper control will lead to uneven morphology of the obtained product.

[0005] Therefore, as a novel visible light-responsive catalyst, silver vanadate is of great practical significance to study its simple preparation process and achieve efficient photodegradation of organic pollutants. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a silver vanadate photocatalyst and its preparation method, which is low in cost, simple in process, easy to control under conditions, and produces Ag3VO4 photocatalytic material with excellent photocatalytic performance.

[0007] The technical problem to be solved by the present invention is to provide a lighting fixture that integrates a silver vanadate photocatalyst to achieve efficient photodegradation of organic pollutants.

[0008] To solve the above problems, the present invention is achieved through the following technical solution: A method for preparing a silver vanadate photocatalytic material includes the following specific steps: Weigh out NH4VO3 and AgNO3 and dissolve them separately in deionized water. Mix them after magnetic stirring and stir until homogeneous to obtain mixed solution A. An alkaline reagent is added to the mixed solution A, and the pH value is adjusted to a preset value to obtain mixed solution B; The mixed solution B was subjected to a hydrothermal synthesis reaction at a temperature of 180-200°C. After the reaction was completed, the solution was cooled to room temperature to obtain the initial product. The initial product was washed with anhydrous ethanol and deionized water and then dried under vacuum to obtain Ag3VO4 photocatalytic material.

[0009] Preferably, the weight ratio of NH4VO3 to AgNO3 is 1:1 to 1:4.

[0010] Preferably, the weight parts of NH4VO3 added are 0.1g~0.4g, the weight parts of AgNO3 added are 0.1g~1.6g, and the volume of deionized water is 20ml~40ml.

[0011] Preferably, the alkaline reagent is either sodium hydroxide or ammonia water, and the preset pH value is 5-8.

[0012] Preferably, the hydrothermal synthesis reaction temperature is 160℃~200℃, and the reaction time is 10h~24h.

[0013] Preferably, the silver vanadate photocatalyst material is rod-shaped with a diameter of 0.005 μm to 0.5 μm and a length of 1 μm to 100 μm.

[0014] Preferably, the silver vanadate photocatalyst material is rod-shaped with a diameter of 0.01 μm to 0.2 μm and a length of 1 μm to 10 μm.

[0015] Accordingly, the present invention also provides a silver vanadate photocatalytic material and a lighting fixture, the lighting fixture including a light-emitting unit coated with the silver vanadate photocatalytic material.

[0016] Typically, high-efficiency photocatalysis requires photocatalysts to possess unique band structures, narrow band gaps, and good visible light response. Silver vanadate has a narrow band gap of approximately 2.0–2.3 eV, corresponding to a light absorption range of 550–620 nm. It can effectively utilize most of the visible light from sunlight and even some near-infrared light, resulting in a solar energy utilization rate far exceeding that of traditional catalysts. Under visible light, it exhibits superior degradation efficiency for various organic pollutants compared to traditional visible light photocatalysts. However, silver ions are easily reduced to elemental silver by their own photogenerated electrons under illumination, leading to catalyst deactivation, blackening, and structural collapse. Although silver vanadate has a very strong absorption capacity for visible light, its recombination rate of photogenerated electrons and holes is very fast, and the low separation efficiency directly results in low quantum yield. Therefore, how to prepare silver vanadate materials with uniform morphology and specific crystal structures on a large scale using simple methods remains a challenge in photocatalyst material preparation. As is well known, the preparation method is a key factor affecting the performance of photocatalytic materials. Different preparation methods can directly affect the crystal structure and morphology of the product, thereby affecting the performance and stability of the photocatalyst.

[0017] This invention provides a silver vanadate photocatalyst material, its preparation, and its application in lighting fixtures. Using NH4VO3 and AgNO3 as raw materials, the pH of the solution is adjusted to 5-8 using sodium hydroxide or ammonia. The Ag3VO4 photocatalyst material is obtained through a one-step hydrothermal reaction in a polytetrafluoroethylene (PTFE) liner. This preparation method does not require additional additives, uses simple and easily recyclable raw materials, has a simple and controllable process, and is low in cost. The resulting product has controllable morphology, uniform particle size, and good dispersibility, exhibiting excellent photocatalytic performance against organic pollutants. When coated onto the light-emitting unit of a lighting fixture, the Ag3VO4 photocatalyst material maintains stable crystal structure and catalytic activity under long-term illumination, enabling the functional application of photocatalytic air purification technology in lighting fixtures.

[0018] Compared with the prior art, the present invention has the following beneficial effects: 1. Process and structural advantages: Overcoming the defects of particle agglomeration and uncontrollable morphology caused by high-temperature calcination of solid-state method, Ag3VO4 photocatalytic material with controllable morphology, uniform particle size and good dispersion is obtained through one-step hydrothermal reaction, without the need for subsequent heat treatment.

[0019] 2. Performance advantages: The Ag3VO4 photocatalytic material prepared by adjusting the pH value has a better photocatalytic degradation rate of organic pollutants such as rotanidine B (RhB) and methylene blue (MB) than the control sample prepared by the traditional method.

[0020] 3. Photocatalytic stability advantage: Ag3VO4 photocatalytic materials can maintain the stability of crystal structure and catalytic activity under long-term light exposure. When integrated with lighting fixtures, they can continuously and efficiently degrade air pollutants and achieve long-lasting air purification function.

[0021] Therefore, this invention solves the problems of particle agglomeration and uncontrollable morphology in silver vanadate photocatalysts prepared by traditional methods. The preparation method of this invention uses simple and easily recyclable raw materials, has a simple and easily controllable process, and is low in cost. The resulting Ag3VO4 photocatalyst can also achieve highly efficient photocatalytic degradation of organic pollutants. Its stable crystal structure and catalytic activity, when integrated with lamps, enable functional applications of photocatalytic air purification technology. Under irradiation with a 300W xenon lamp, the Ag3VO4 photocatalyst shows a degradation rate of 20-25% for commercial P25, a degradation rate of 96-98% for methylene blue (MB), and a degradation rate of 91-93% for rotaminide B (RhB). Attached Figure Description

[0022] Figure 1 This is a TEM image of the Ag3VO4 photocatalytic material.

[0023] Figure 2 The image shows the UV-Vis diffuse reflectance spectrum of the Ag3VO4 photocatalyst material.

[0024] Figure 3 The graph shows the photocatalytic degradation curve of Ag3VO4 material.

[0025] Figure 4 The graph shows the photocatalytic degradation kinetics of Ag3VO4 material. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings.

[0027] A method for preparing a silver vanadate photocatalytic material includes the following specific steps: (1) Weigh NH4VO3 and AgNO3 and dissolve them separately in deionized water. Mix them after magnetic stirring and stir until homogeneous to obtain mixed solution A. Preferably, in step (1), the weight ratio of NH4VO3 to AgNO3 is 1:1 to 1:4.

[0028] Preferably, in step (1), the weight of NH4VO3 added is 0.1g~0.4g, the weight of AgNO3 added is 0.1g~1.6g, and the volume of deionized water is 20ml~40ml.

[0029] This invention uses NH4VO3 and AgNO3 as raw materials, which are simple to select and low in cost. No additional additives are required, there are few variables, the chemical composition is pure, and the reproducibility is high. This is very beneficial for the recycling and utilization of raw materials and also for industrial scale-up.

[0030] (2) Add an alkaline reagent to the mixed solution A and adjust the pH value to a preset value to obtain mixed solution B; Preferably, in step (2), the alkaline reagent is either sodium hydroxide or ammonia water, and the preset pH value is 5 to 8.

[0031] This invention optimizes the photocatalytic performance of silver vanadate by controlling the pH value. pH has a decisive influence on the preparation of silver vanadate, directly controlling the phase composition, crystal structure, morphology, and photocatalytic performance of the product. Low pH values ​​tend to generate silver metavanadate (AgVO3), while medium pH values ​​are the ideal range for preparing silver orthovanadate (Ag3VO4). High pH values, however, easily generate impurities and lead to instability of silver vanadate. The initially formed precipitate may be amorphous, but the subsequent pH environment affects its transformation to a crystalline state and the final crystal form during the hydrothermal reaction. pH also affects the existence form and concentration of precursor ions, thereby altering the kinetics of the precipitation reaction. Under different pH conditions, the rates of crystal nucleation and growth vary, leading to significant changes in the particle size and morphology of the product. Therefore, controlling the pH environment of the solution before the hydrothermal reaction is crucial.

[0032] In addition, by precisely controlling the pH, this invention can selectively synthesize phases with specific band structures, thereby optimizing their absorption range of sunlight and the separation efficiency of photogenerated electron-hole pairs, and ultimately achieving their photocatalytic activity. Preferably, this invention controls the pH value in the range of 5 to 8, and the product obtained is an Ag3VO4 photocatalyst material with good visible light response.

[0033] (3) The mixed solution B is subjected to a hydrothermal synthesis reaction at a temperature of 180~200℃. After the reaction is completed, the solution is cooled to room temperature to obtain the initial product. Preferably, in step (3), the hydrothermal synthesis reaction temperature is 160℃~200℃ and the reaction time is 10h~24h.

[0034] The hydrothermal reaction of this invention is carried out in a polytetrafluoroethylene (PTFE) liner. Only one hydrothermal reaction step is required to obtain the reaction product. The process is simple, the conditions are easily controlled, and a well-crystallized product with controllable morphology can be directly obtained without subsequent high-temperature calcination. Figure 1 As shown, the Ag3VO4 photocatalytic material obtained by adjusting the pH value of the solution before the reaction and then undergoing a hydrothermal reaction is slender and rod-shaped with controllable morphology, uniform particle size and good dispersibility. This phase composition and crystal structure determine its excellent photocatalytic performance.

[0035] (4) The initial product was washed with anhydrous ethanol and deionized water and then dried under vacuum to obtain Ag3VO4 photocatalytic material.

[0036] Preferably, in step (4), the silver vanadate photocatalyst material is rod-shaped with a diameter of 0.005 μm to 0.5 μm and a length of 1 μm to 100 μm. More preferably, the silver vanadate photocatalyst material is rod-shaped with a diameter of 0.01 μm to 0.2 μm and a length of 1 μm to 10 μm.

[0037] This invention controls the solution pH within the range of 5-8, and the product obtained through a one-step hydrothermal reaction is silver vanadate (Ag3VO4) photocatalytic material. Due to its narrow band gap and efficient visible light response, it is generally superior to silver metavanadate (AgVO3) in photocatalytic degradation. Figure 2 As shown, Ag3VO4 photocatalysts exhibit strong absorption of visible light, high separation efficiency of photogenerated electron-hole pairs, relatively low photocorrosion, good stability, and strong hole oxidation capacity, making them suitable for degrading organic pollutants. In contrast, AgVO3 photocatalysts show stronger response to ultraviolet light, lower utilization of visible light, potential structural transformation under illumination, poor stability, weaker oxidation capacity, and generally lower catalytic activity than Ag3VO4.

[0038] Therefore, the Ag3VO4 photocatalytic material described in this invention exhibits highly efficient photocatalytic performance for any of the organic pollutants, including commercially available P25, methylene blue (MB), and rhodamine B (RhB). Under irradiation with a 300W xenon lamp, after 25 minutes of degradation, the Ag3VO4 photocatalytic material achieves a degradation rate of 20%–25% for commercially available P25, a degradation rate of 96%–98% for methylene blue (MB), and a degradation rate of 91%–93% for rhodamine B (RhB). In contrast, the existing silver metavanadate AgVO3 photocatalyst, under visible light irradiation, only achieves a degradation rate of 65% for rhodamine B within 200 minutes. This demonstrates that the Ag3VO4 photocatalytic material has a significantly higher photocatalytic degradation effect on organic pollutants than silver metavanadate AgVO3. Furthermore, the Ag3VO4 photocatalytic material exhibits photocatalytic degradation activity for a variety of organic pollutants.

[0039] It should be further noted that the Ag3VO4 photocatalytic material described in this invention exhibits long-term stability when applied in lighting fixtures, such as... Figure 4As shown, both sample lamps remained stable under long-term illumination, indicating that the material can maintain its crystal structure and photocatalytic degradation performance for a long time under visible light irradiation without significant deactivation or decomposition, thus sustainably and efficiently degrading air pollutants. This invention overcomes the inherent defects of silver-based photocatalysts. Silver-based materials are easily reduced to elemental silver by their own photogenerated electrons under light, leading to catalyst structural collapse, which is currently a major obstacle to commercialization. The Ag3VO4 photocatalytic material prepared by the method of this invention exhibits long-term stability under long-term illumination, proving that this silver vanadate material, through its specific crystal structure, greatly inhibits the photoinduced reduction of silver ions, fundamentally solving the stability problem. Furthermore, the superior stability indicates that the valence band and conduction band positions of this material make it less prone to self-decomposition reactions, exhibiting excellent resistance to photocorrosion. Long-term stability means that the active sites on the surface of the Ag3VO4 photocatalytic material are not poisoned, covered, or destroyed during the reaction process, enabling the continuous and efficient generation of free radicals and electron-hole pairs.

[0040] In summary, this invention solves the problems of complex processes, easy product agglomeration, and poor photocatalytic degradation effect in existing technologies. This invention provides a method for preparing silver vanadate photocatalytic materials, which adopts a one-step hydrothermal method to prepare Ag3VO4 by controlling the pH value. The morphology is controllable, the particle size is uniform and the dispersion is good. It has the advantages of less raw materials, low cost, simple process and easy control of conditions. It has a good photocatalytic degradation effect on organic pollutants. The product of this preparation method can maintain the stability of Ag3VO4 crystal structure and catalytic activity. When integrated with lighting fixtures, it can realize the functional application of photocatalytic air purification technology, which has important practical significance.

[0041] The present invention will be further illustrated below with specific embodiments.

[0042] Example 1: 1. Preparation: 0.2282 g of NH4VO3 and 0.6645 g of AgNO3 were weighed and dissolved in 30 ml of deionized water. After stirring magnetically for 30 min, the mixture was stirred evenly. The pH of the mixed solution was adjusted to 5 with ammonia water. The solution was then transferred to a polytetrafluoroethylene liner and hydrothermally reacted at 160 °C for 12 h. After the reaction was completed, the solution was cooled to room temperature and washed several times with anhydrous ethanol and deionized water. Finally, the product was vacuum dried overnight to obtain Ag3VO4 photocatalytic material.

[0043] 2. Performance Analysis: After testing, Figure 1 The TEM image of the Ag3VO4 photocatalyst material is shown below. The testing method is as follows: The Ag3VO4 photocatalyst material obtained above was ultrasonically dispersed in ethanol. The dispersion was pipetted onto a copper grid for TEM testing. After drying, its morphology was characterized using a transmission electron microscope. Figure 1 It can be seen that the obtained Ag3VO4 photocatalytic material is slender and rod-shaped, with controllable morphology, uniform particle size and good dispersibility. Figure 2 The UV-Vis diffuse reflectance spectrum of the Ag3VO4 photocatalyst material was obtained using the following method: After thorough drying, the Ag3VO4 photocatalyst material was ground into a fine powder with uniform particle size. This powder was then filled into a dedicated diffuse reflectance sample cell, gently leveled, and lightly compacted. The sample was then tested using a UV-Vis-NIR diffuse reflectance spectrometer. Figure 2 It is known that Ag3VO4 photocatalytic material has a very strong absorption capacity for visible light and can be widely used in lighting fixtures to realize the functional application of photocatalytic air purification technology.

[0044] Figure 3 The photocatalytic degradation curve of Ag3VO4 material is shown in Table 1, which illustrates its photocatalytic performance. Table 1 presents the specific data records of the degradation effect of the Ag3VO4 photocatalytic material. The test methods are as follows: Commercially available P25, methylene blue (MB), and rotanamine B (RhB) were used as simulated pollutants to evaluate the photocatalytic performance. 50 mg of Ag3VO4 photocatalytic material and 5 mL of the target pollutant (1×10⁻⁶) were weighed. 5 The Ag3VO4 photocatalytic material was thoroughly mixed with a mol / L solution and placed in complete darkness (a light-protected environment) with magnetic stirring for 30 min to reach adsorption-desorption equilibrium. Then, a 300 W xenon lamp was used as the light source for photocatalytic degradation. Samples of 5 mL were taken periodically. Finally, the solid particles of the Ag3VO4 photocatalytic material were removed by centrifugation, and the absorbance of the supernatant was measured. Figure 3 As shown in Table 1, under irradiation by a 300W xenon lamp, after 25 minutes of degradation reaction, the Ag3VO4 photocatalyst material achieved a degradation rate of 20.06% for commercial P25, a degradation rate of up to 96.82% for methylene blue, and a degradation rate of up to 91.73% for rhodamine B. This demonstrates that the Ag3VO4 photocatalyst material has a highly efficient photocatalytic degradation effect on organic pollutants, and the degradation effect varies for different organic pollutants. More specifically: methylene blue (MB) > rhodamine B (RhB) > commercial P25.

[0045] Table 1 shows the degradation effects of different materials in Example 1.

[0046] Example 2: 1. Preparation: 0.1521 g of NH4VO3 and 0.2215 g of AgNO3 were weighed and dissolved in 30 ml of deionized water, respectively. After stirring magnetically for 30 min, the mixture was stirred until homogeneous. The pH of the mixed solution was adjusted to 7 with ammonia. The solution was transferred to a polytetrafluoroethylene liner and reacted at 180 °C for 12 h. After cooling to room temperature, the mixture was washed several times with anhydrous ethanol and deionized water, and finally dried under vacuum overnight to obtain the Ag3VO4 photocatalytic material.

[0047] 2. Performance Analysis: Table 2 shows the specific data record of the degradation effect of Ag3VO4 photocatalytic material in Example 2. The test method is as follows: Commercial P25, methylene blue (MB), and rotanamine B (RhB) were used as simulated pollutants to evaluate the photocatalytic performance. 50 mg of Ag3VO4 photocatalytic material and 5 mL of target pollutant (1×10⁻⁶) were weighed. 5 The Ag3VO4 photocatalyst solution was thoroughly mixed and placed in a completely dark environment with magnetic stirring for 30 min to reach adsorption-desorption equilibrium. Then, a 300 W xenon lamp was used as the light source for photocatalytic degradation. Samples were taken at regular intervals, 5 mL each time. Finally, the solid particles of the Ag3VO4 photocatalyst were removed by centrifugation, and the absorbance of the supernatant was measured. Table 2 shows that under 300 W xenon lamp irradiation, after 25 min of degradation, the Ag3VO4 photocatalyst achieved a degradation rate of 21.25% for commercial P25, a degradation rate of 96.95% for methylene blue, and a degradation rate of 93.00% for Rhodamine B. This demonstrates that the Ag3VO4 photocatalyst exhibits highly efficient photocatalytic degradation of organic pollutants, with varying degradation effects on different pollutants. Specifically: Methylene blue (MB) > Rhodamine B (RhB) > Commercial P25.

[0048] Table 2 shows the degradation effects of different materials in Example 2.

[0049] Example 3: 1. Preparation: 0.3195 g of NH4VO3 and 0.9968 g of AgNO3 were weighed and dissolved in 30 ml of deionized water respectively. After stirring magnetically for 30 min, the mixture was stirred until homogeneous. The pH of the mixed solution was adjusted to 8 with NaOH. The solution was transferred to a polytetrafluoroethylene liner and reacted at 200 °C for 12 h. After cooling to room temperature, the solution was washed several times with anhydrous ethanol and deionized water, and finally dried under vacuum overnight to obtain Ag3VO4 photocatalytic material.

[0050] 2. Performance Analysis: Table 3 shows the specific data record of the degradation effect of Ag3VO4 photocatalytic material in Example 3. The test method is as follows: Commercial P25, methylene blue (MB), and rotanamine B (RhB) were used as simulated pollutants to evaluate the photocatalytic performance. 50 mg of Ag3VO4 photocatalytic material and 5 mL of target pollutant (1×10⁻⁶) were weighed. 5 The Ag3VO4 photocatalyst solution was mixed thoroughly and placed in a dark environment (completely protected from light) with magnetic stirring for 30 min to reach adsorption-desorption equilibrium. Then, a 300 W xenon lamp was used as the light source for photocatalytic degradation. Samples were taken at regular intervals, 5 mL each time. Finally, the solid particles of the Ag3VO4 photocatalyst were removed by centrifugation, and the absorbance of the supernatant was measured. Table 3 shows that under 300 W xenon lamp irradiation, after 25 min of degradation, the Ag3VO4 photocatalyst achieved a degradation rate of 25.00% for commercial P25, a degradation rate of up to 96.05% for methylene blue, and a degradation rate of up to 91.86% for Rhodamine B. This demonstrates that the Ag3VO4 photocatalyst exhibits highly efficient photocatalytic degradation of organic pollutants, with varying degradation effects on different pollutants. Specifically: Methylene blue (MB) > Rhodamine B (RhB) > Commercial P25.

[0051] Table 3 shows the degradation effects of different materials in Example 3.

[0052] Example 4: 1. Preparation 0.2282 g of NH4VO3 and 0.9128 g of AgNO3 were weighed and dissolved in 30 ml of deionized water respectively. After stirring magnetically for 30 min, the mixture was stirred until homogeneous. The pH of the mixed solution was adjusted to 6 with NaOH. The solution was transferred to a polytetrafluoroethylene liner and reacted at 180 °C for 24 h. After cooling to room temperature, the solution was washed several times with anhydrous ethanol and deionized water, and finally dried under vacuum overnight to obtain Ag3VO4 photocatalytic material.

[0053] 2. Performance Analysis: Table 4 shows the specific data record of the degradation effect of Ag3VO4 photocatalytic material in Example 4. The test method is as follows: Commercial P25, methylene blue (MB), and rotanamine B (RhB) were used as simulated pollutants to evaluate the photocatalytic performance. 50 mg of Ag3VO4 photocatalytic material and 5 mL of target pollutant (1×10⁻⁶) were weighed. 5The Ag3VO4 photocatalyst solution was thoroughly mixed and placed in a completely dark environment with magnetic stirring for 30 min to reach adsorption-desorption equilibrium. Then, a 300 W xenon lamp was used as the light source for photocatalytic degradation. Samples were taken at regular intervals, 5 mL each time. Finally, the solid particles of the Ag3VO4 photocatalyst were removed by centrifugation, and the absorbance of the supernatant was measured. Table 4 shows that under 300 W xenon lamp irradiation, after 25 min of degradation, the Ag3VO4 photocatalyst achieved a degradation rate of 20.02% for commercial P25, a degradation rate of 97.99% for methylene blue, and a degradation rate of 91.00% for Rhodamine B. This demonstrates that the Ag3VO4 photocatalyst exhibits highly efficient photocatalytic degradation of organic pollutants, with varying degradation effects on different pollutants. Specifically: Methylene blue (MB) > Rhodamine B (RhB) > Commercial P25.

[0054] Table 4 shows the degradation effects of different materials in Example 4.

[0055] Example 5: 1. Preparation 0.1006 g of NH4VO3 and 0.1015 g of AgNO3 were weighed and dissolved in 20 ml of deionized water, respectively. After stirring magnetically for 30 min, the mixture was stirred until homogeneous. The pH of the mixed solution was adjusted to 7 with NaOH. The solution was transferred to a polytetrafluoroethylene liner and reacted at 170 °C for 16 h. After cooling to room temperature, the solution was washed several times with anhydrous ethanol and deionized water, and finally dried under vacuum overnight to obtain the Ag3VO4 photocatalytic material.

[0056] 2. Performance Analysis: Table 5 shows the specific data record of the degradation effect of Ag3VO4 photocatalytic material in Example 5. The test method is as follows: Commercial P25, methylene blue (MB), and rotanamine B (RhB) were used as simulated pollutants to evaluate the photocatalytic performance. 50 mg of Ag3VO4 photocatalytic material and 5 mL of target pollutant (1×10⁻⁶) were weighed. 5The Ag3VO4 photocatalyst solution was mixed thoroughly and placed in a dark environment (completely protected from light) with magnetic stirring for 30 min to reach adsorption-desorption equilibrium. Then, a 300 W xenon lamp was used as the light source for photocatalytic degradation. Samples were taken at regular intervals, 5 mL each time. Finally, the solid particles of the Ag3VO4 photocatalyst were removed by centrifugation, and the absorbance of the supernatant was measured. Table 5 shows that under 300 W xenon lamp irradiation, after 25 min of degradation, the Ag3VO4 photocatalyst achieved a degradation rate of 23.21% for commercial P25, a degradation rate of 96.90% for methylene blue, and a degradation rate of 92.29% for Rhodamine B. This demonstrates that the Ag3VO4 photocatalyst exhibits highly efficient photocatalytic degradation of organic pollutants, with varying degradation effects on different pollutants. Specifically: Methylene blue (MB) > Rhodamine B (RhB) > Commercial P25.

[0057] Table 5 shows the degradation effects of different materials in Example 5.

[0058] Example 6: 1. Preparation 0.3998 g of NH4VO3 and 1.5992 g of AgNO3 were weighed and dissolved in 40 ml of deionized water, respectively. After stirring magnetically for 30 min, the mixture was stirred until homogeneous. The pH of the mixed solution was adjusted to 5 with NaOH. The solution was transferred to a polytetrafluoroethylene liner and reacted at 200 °C for 10 h. After cooling to room temperature, the solution was washed several times with anhydrous ethanol and deionized water, and finally dried under vacuum overnight to obtain the Ag3VO4 photocatalytic material.

[0059] 2. Performance Analysis: Table 6 shows the specific data record of the degradation effect of Ag3VO4 photocatalytic material in Example 6. The test method is as follows: Commercial P25, methylene blue (MB), and rotanamine B (RhB) were used as simulated pollutants to evaluate the photocatalytic performance. 50 mg of Ag3VO4 photocatalytic material and 5 mL of target pollutant (1×10⁻⁶) were weighed. 5The Ag3VO4 photocatalyst solution was thoroughly mixed and placed in a completely dark environment with magnetic stirring for 30 min to reach adsorption-desorption equilibrium. Then, a 300 W xenon lamp was used as the light source for photocatalytic degradation. Samples were taken at regular intervals, 5 mL each time. Finally, the solid particles of the Ag3VO4 photocatalyst were removed by centrifugation, and the absorbance of the supernatant was measured. Table 6 shows that under 300 W xenon lamp irradiation, after 25 min of degradation, the Ag3VO4 photocatalyst achieved a degradation rate of 22.09% for commercial P25, a degradation rate of 96.80% for methylene blue, and a degradation rate of 91.71% for Rhodamine B. This demonstrates that the Ag3VO4 photocatalyst exhibits highly efficient photocatalytic degradation of organic pollutants, with varying degradation effects on different pollutants. Specifically: Methylene blue (MB) > Rhodamine B (RhB) > Commercial P25.

[0060] Table 6 shows the degradation effects of different materials in Example 6.

[0061] Application example: The Ag3VO4 photocatalyst material obtained in Example 1 was applied to a panel lamp, and the panel lamp was coated with the silver vanadate photocatalyst material.

[0062] After testing, Figure 4 The photocatalytic degradation kinetics curve of Ag3VO4 material is shown below. The test method is as follows: Ag3VO4 material was coated on the surface of a 600*600mm panel light, and these were designated as sample light ① and sample light ②, respectively. The organic dye Rhodamine B (1×10⁻⁶) was applied... - 5 A mol / L solution was dropped onto the surface of the sample lamp, and the stability of the panel lamp was evaluated by irradiating it with the lamp until the Rhodamine B solution completely decolorized. Figure 4 It can be seen that both sample lamp ① and sample lamp ② exhibit excellent stability under long-term illumination. This indicates that the Ag3VO4 photocatalytic material can maintain the stability of its crystal structure and catalytic activity under long-term illumination, enabling it to continuously and efficiently degrade air pollutants and achieve a long-lasting air purification function when applied to lighting fixtures.

[0063] The above description represents a preferred embodiment of the present invention, but it should not be construed as limiting the scope of the invention. Therefore, any equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. A method for preparing a silver vanadate photocatalytic material, characterized in that, The specific steps include the following: Weigh out NH4VO3 and AgNO3 and dissolve them separately in deionized water. Mix them after magnetic stirring and stir until homogeneous to obtain mixed solution A. An alkaline reagent is added to the mixed solution A, and the pH value is adjusted to a preset value to obtain mixed solution B; The mixed solution B was subjected to a hydrothermal synthesis reaction at a temperature of 180-200°C. After the reaction was completed, the solution was cooled to room temperature to obtain the initial product. The initial product was washed with anhydrous ethanol and deionized water and then dried under vacuum to obtain Ag3VO4 photocatalytic material.

2. The method for preparing the silver vanadate photocatalyst material according to claim 1, characterized in that, The weight ratio of NH4VO3 to AgNO3 is 1:1 to 1:

4.

3. The method for preparing the silver vanadate photocatalyst material according to claim 1, characterized in that, The amount of NH4VO3 added is 0.1g~0.4g by weight, the amount of AgNO3 added is 0.1g~1.6g by weight, and the volume of deionized water is 20ml~40ml.

4. The method for preparing the silver vanadate photocatalyst material according to claim 1, characterized in that, The alkaline reagent is either sodium hydroxide or ammonia water, and the preset pH value is 5-8.

5. The method for preparing the silver vanadate photocatalyst material according to claim 1, characterized in that, The hydrothermal synthesis reaction temperature is 160℃~200℃, and the reaction time is 10h~24h.

6. The method for preparing the silver vanadate photocatalyst material according to claim 1, characterized in that, The silver vanadate photocatalyst material is rod-shaped with a diameter of 0.005 μm to 0.5 μm and a length of 1 μm to 100 μm.

7. The method for preparing the silver vanadate photocatalyst material according to claim 6, characterized in that, The silver vanadate photocatalyst material is rod-shaped with a diameter of 0.01 μm to 0.2 μm and a length of 1 μm to 10 μm.

8. A silver vanadate photocatalyst material, characterized in that, It is prepared by the method for preparing silver vanadate photocatalyst material according to any one of claims 1-7.

9. A lighting fixture, characterized in that, The lighting fixture includes a light-emitting unit, and the light-emitting unit is coated with the silver vanadate photocatalytic material as described in claim 8.

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