Preparation method and application of a MoS2 / h-BN composite piezoelectric catalyst

Abstract

The present invention discloses a preparation method and application of a MoS2 / h-BN composite piezoelectric catalyst. The preparation of the composite piezoelectric catalyst uses thiourea, sodium molybdate dihydrate, urea, and boric acid as raw materials, and MoS2 NFs (nano-flowers) and h-BN are obtained by hydrothermal synthesis method and high-temperature calcination method respectively. The MoS2 / h-BN composite piezoelectric catalyst is obtained by adding water and stirring, wherein the stirring time is 8 to 12 h. The MoS2 / h-BN composite piezoelectric catalyst prepared by the present invention has a simple preparation process and a large yield, and has the characteristics of high catalytic activity and many reaction sites. This material can activate persulfate under ultrasonic conditions and efficiently catalytically degrade bisphenol F in water.

Description

Technical Field

[0001] The present invention belongs to the field of preparation of electrocatalysts, and particularly relates to a preparation method and application of a MoS2 / h-BN composite piezoelectric catalyst. Background Art

[0002] Bisphenol A (BPA), as a representative of endocrine disrupting chemicals (EDCs), is widely used in the production of various chemical materials such as polycarbonate plastics and epoxy resins. Due to the potential adverse effects of BPA on human health, there is increasing concern about it, and many countries have prohibited the use of BPA in certain products, such as Canada, China, and the European Union. Therefore, manufacturers must use BPA substitutes to comply with the new regulations.

[0003] Bisphenol-f (4,4'-dihydroxydiphenylmethane, BPF) is widely used in various industrial applications due to its excellent thermal stability and light stability, and is considered a "safer" substitute for BPA. Despite this stability, BPF has been frequently detected in environmental matrices in the past years of research. The potential adverse effects of BPF on humans have been discovered by many researchers, including cytotoxicity, neurotoxicity, reproductive toxicity, genotoxicity, and carcinogenicity, which directly pose a threat to human health. Therefore, the research on BPF removal methods has important practical significance.

[0004] Molybdenum disulfide (MoS2) is a typical two-dimensional piezoelectric material with a large specific surface area, multiple active sites, strong adsorption performance, and high piezoelectric response. In recent years, MoS2 materials have received extensive attention as piezoelectric catalysts for removing organic pollutants. Hexagonal boron nitride (h-BN), as a graphite-like two-dimensional material with a piezoelectric nanostructure, exhibits high organic pollutant adsorption characteristics and photocatalytic properties due to the polarity of its B-N bond and wide bandgap, so it has also been widely used in the research of environmental functional materials.

[0005] Currently, there are many studies on the respective composites of MoS2 and BN, but the heterostructure composite piezoelectric material of MoS2 and BN has not been reported so far, and its piezoelectric catalytic mechanism is still unclear. Summary of the Invention

[0006] The purpose of this part is to outline some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this part, as well as in the abstract and title of the present application, to avoid obscuring the purpose of this part, the abstract, and the title, but such simplifications or omissions cannot be used to limit the scope of the present invention.

[0007] In view of the above and / or problems existing in the prior art, the present invention is proposed.

[0008] Therefore, the object of the present invention is to overcome the deficiencies in the prior art and provide a preparation method of MoS2 / h-BN composite piezoelectric catalyst.

[0009] To solve the above technical problems, the present invention provides the following technical solutions: A preparation method of MoS2 / h-BN composite piezoelectric catalyst, comprising,

[0010] Dissolve thiourea and sodium molybdate dihydrate in water, add hydrochloric acid to adjust the pH, and heat to obtain a hydrothermal product;

[0011] Filter and wash the hydrothermal product to neutrality, and dry to obtain MoS2NFs powder;

[0012] Dissolve urea and boric acid in ultrapure water, heat to produce a white solid, calcine at high temperature, and grind to obtain h-BN powder;

[0013] Add MoS2NFs and h-BN to ultrapure water and mix, centrifuge, wash and dry to obtain the product MoS2 / h-BN composite piezoelectric catalyst.

[0014] As a preferred embodiment of the preparation method of the present invention, wherein: the mass ratio of the thiourea to the sodium molybdate dihydrate is 3:4 to 10.

[0015] As a preferred embodiment of the preparation method of the present invention, wherein: adding hydrochloric acid to adjust the pH and heating to obtain a hydrothermal product, wherein the pH value is 1, the heating temperature is 180 to 200 °C, and the reaction time is 20 to 24 h.

[0016] As a preferred embodiment of the preparation method of the present invention, wherein: the pore size of the filter membrane used during filtration is 0.22 to 0.45 μm, drying to obtain MoS2NFs powder, the drying temperature is 50 to 70 °C, and the drying type is vacuum drying.

[0017] As a preferred embodiment of the preparation method of the present invention, wherein: the molar ratio of the urea to the boric acid is 1:40 to 50.

[0018] As a preferred embodiment of the preparation method of the present invention, wherein: heating to produce a white solid and calcining at high temperature, wherein the heating temperature is 60 to 70 °C, the high-temperature calcination is carried out in a nitrogen atmosphere, the temperature is 800 to 1000 °C, and the calcination time is 4 to 6 h.

[0019] As a preferred embodiment of the preparation method of the present invention, wherein: adding MoS2NFs and h-BN to ultrapure water and mixing, wherein the mass ratio of MoS2 to h-BN is 1:1 to 98:2, and the mixing time is 8 to 12 h.

[0020] As a preferred embodiment of the preparation method of the present invention, the centrifugation speed is 8000-9000 r / min, and the centrifugation time is 4-6 min.

[0021] Another object of the present invention is to overcome the deficiencies in the prior art and provide a MoS2 / h-BN composite piezoelectric catalyst product.

[0022] Another object of the present invention is to overcome the deficiencies in the prior art and provide an application of a composite piezoelectric catalyst in the degradation of bisphenol F in water, including

[0023] adding MoS2 / h-BN composite piezoelectric catalyst to the bisphenol F solution;

[0024] adding persulfate to carry out a piezoelectric catalytic reaction;

[0025] wherein, the mass ratio of the piezoelectric catalyst to bisphenol F is 20-100:1, and the mass ratio of the piezoelectric catalyst to persulfate is 25:10-60.78.

[0026] Advantages of the present invention:

[0027] (1) The preparation method of the present invention obtains MoS2NFs through organic synthesis and obtains a MoS2 / h-BN composite piezoelectric catalyst through mixing. It has low cost, simple process, and large output.

[0028] (2) The catalyst prepared by the preparation method of the present invention can be applied to the degradation of bisphenol F in water. This catalyst can efficiently catalyze the degradation of bisphenol F in water, and the highest removal rate of bisphenol F can reach 84.2% in 30 min.

[0029] (3) The piezoelectric catalyst of the present invention can activate persulfate under ultrasound. Compared with the traditional ultraviolet light activation of persulfate, it has low energy consumption and low cost. Description of the Drawings

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings. Among them:

[0031] Figure 1 is the scanning electron microscope image of MoS2NFs in the embodiment of the present invention;

[0032] Figure 2 is the scanning electron microscope image of h-BN in the embodiment of the present invention;

[0033] Figure 3 Transmission electron microscopy image of h-BN in the embodiment of the present invention;

[0034] Figure 4 Scanning electron microscopy image of MoS2 / 0.20BN composite piezoelectric catalyst in Example 1 of the present invention;

[0035] Figure 5 Comparison chart of the effects of different materials prepared by the present invention on activating PMS to degrade 10 mg / L bisphenol F under ultrasound;

[0036] Figure 6 Comparison chart of the reaction kinetic constants of different materials prepared by the present invention on activating PMS to degrade 10 mg / L bisphenol F under ultrasound. Detailed implementation manners

[0037] To make the above objects, features and advantages of the present invention more obvious and understandable, the following detailed description of the specific implementation manners of the present invention is made in conjunction with the embodiments of the specification.

[0038] In the following description, many specific details are set forth to fully understand the present invention. However, the present invention can also be implemented in other ways different from those described herein. Those skilled in the art can make similar generalizations without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0039] Secondly, the so-called "one embodiment" or "embodiment" herein refers to a specific feature, structure or characteristic that can be included in at least one implementation manner of the present invention. The "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a separate or selectively exclusive embodiment from other embodiments.

[0040] Example 1

[0041] The preparation method of the MoS2 / h-BN composite piezoelectric catalyst in this embodiment includes the following steps:

[0042] (1) Dissolve thiourea and sodium molybdate dihydrate in 90 mL of ultrapure water according to a mass ratio of 3:4 (0.9 g, 1.2 g), adjust the pH = 1 with hydrochloric acid, and place it in a polytetrafluoroethylene inner liner at a temperature of 180 °C for organic synthesis for 24 h;

[0043] (2) Filter, wash the hydrothermal product to neutrality and dry it to obtain MoS2NFs powder, wherein the pore size of the filter membrane for filtration is 0.22 μm, and the drying temperature is 60 °C;

[0044] (3) Urea and boric acid in a molar ratio of 1:40 (1 mol, 40 mol) were dissolved in 40 mL of ultrapure water, and the mixed solution was heated at 65° C. to perform organic synthesis to produce a white solid, which was then calcined at a high temperature of 4° C. / min to 900° C. for 5 h in a nitrogen atmosphere, and then ground to obtain h-BN powder;

[0045] (4) MoS2 and h-BN with a mass ratio of 4:1 (80 mg, 20 mg) were placed in 30 mL of ultrapure water and stirred for 8 h. The resulting uniform suspension was centrifuged, washed, and dried to obtain the product MoS2 / h-BN composite piezoelectric catalyst, recorded as MoS2 / 0.20BN;

[0046] The MoS2 / h-BN composite piezoelectric catalyst obtained by the preparation method can be used to degrade bisphenol F in water, and the steps are as follows:

[0047] Take 10 mg of MoS2 / h-BN composite piezoelectric catalyst, put it in 50 mL of bisphenol F solution (10 mg / L), let it stand for 30 min in dark conditions, and after reaching adsorption equilibrium, turn on the ultrasonic reactor (US=120W), add peroxymonosulfate at this time, mix well to obtain the MoS2 / h-BN composite piezoelectric catalyst activated peroxymonosulfate system under ultrasonic conditions, wherein the mass ratio of MoS2 / h-BN to bisphenol F is 20:1, and the mass ratio of MoS2 / h-BN to peroxymonosulfate is 10:46.11.

[0048] Figure 1 This is a scanning electron microscope image of MoS2NFs, showing nanoflower shape.

[0049] Figure 2 This is a scanning electron microscope image of h-BN. Figure 3 This is a transmission electron microscope image of h-BN. The morphology of h-BN is complete and round. Figure 4 This is a scanning electron microscope image of the MoS2 / 0.20BN composite piezoelectric catalyst. It can be seen that h-BN is successfully embedded in MoS2, indicating that the two are successfully composited.

[0050] Example 2

[0051] The preparation method of the MoS2 / h-BN composite piezoelectric catalyst of this embodiment comprises the following steps:

[0052] (1) Dissolve thiourea and sodium molybdate dihydrate in 90 mL of ultrapure water at a mass ratio of 3:4 (0.9 g, 1.2 g), adjust pH to 1 with hydrochloric acid, and place in a polytetrafluoroethylene liner at 180° C. for organic synthesis for 24 h;

[0053] (2) Filter, wash the hydrothermal product to neutrality and dry it to obtain MoS2NFs powder. Among them, the pore size of the filter membrane for filtration is 0.22 μm, and the drying temperature is 60 °C;

[0054] (3) Dissolve urea and boric acid at a molar ratio of 1:40 (1 mol, 40 mol) in 40 mL of ultrapure water, heat the mixed solution at 65 °C for organic synthesis to produce a white solid, and calcine it at a heating rate of 4 °C / min to 900 °C for 5 h in a nitrogen atmosphere, and grind it to obtain h-BN powder;

[0055] (4) Put MoS2 and h-BN with a mass ratio of 98:2 (98 mg, 2 mg) into 30 mL of ultrapure water and stir for 8 h. Centrifuge, wash and dry the obtained uniform suspension to obtain the product MoS2 / h-BN composite piezoelectric catalyst, denoted as MoS2 / 0.02BN;

[0056] The MoS2 / h-BN composite piezoelectric catalyst obtained by the preparation method can be applied to the degradation of bisphenol F in water, and the steps are as follows:

[0057] Take 10 mg of MoS2 / h-BN composite piezoelectric catalyst and place it in 50 mL of bisphenol F solution (10 mg / L). First, let it stand still for 30 min under dark conditions. After reaching the adsorption equilibrium, turn on the ultrasonic reactor (US = 120 W). At this time, add persulfate, and mix evenly to obtain the system of MoS2 / h-BN composite piezoelectric catalyst activating persulfate under ultrasonic conditions. Among them, the mass ratio of MoS2 / h-BN to bisphenol F is 20:1, and the mass ratio of MoS2 / h-BN to persulfate is 10:46.11.

[0058] Example 3

[0059] The preparation method of the MoS2 / h-BN composite piezoelectric catalyst in this example includes the following steps:

[0060] (1) Dissolve thiourea and sodium molybdate dihydrate at a mass ratio of 3:4 (0.9 g, 1.2 g) in 90 mL of ultrapure water, adjust the pH = 1 with hydrochloric acid, and place it in a polytetrafluoroethylene inner liner at a temperature of 160 °C for organic synthesis for 24 h;

[0061] (2) Filter, wash the hydrothermal product to neutrality and dry it to obtain MoS2NFs powder. Among them, the pore size of the filter membrane for filtration is 0.22 μm, and the drying temperature is 60 °C;

[0062] (3) Dissolve urea and boric acid in a molar ratio of 1:40 (1 mol, 40 mol) in 40 mL of ultrapure water, heat the mixed solution at 65 °C for organic synthesis to produce a white solid, and perform high-temperature calcination in a nitrogen atmosphere. Heat it to 900 °C at a rate of 4 °C / min and calcine for 5 h, then grind to obtain h-BN powder;

[0063] (4) Put MoS2 and h-BN with a mass ratio of 95:5 (95 mg, 5 mg) into 30 mL of ultrapure water and stir for 8 h. Centrifuge, wash, and dry the obtained homogeneous suspension to obtain the product MoS2 / h-BN composite piezoelectric catalyst, denoted as MoS2 / 0.05BN;

[0064] The MoS2 / h-BN composite piezoelectric catalyst obtained by the preparation method can be applied to the degradation of bisphenol F in water, and the steps are as follows:

[0065] Take 10 mg of the MoS2 / h-BN composite piezoelectric catalyst and place it in 50 mL of bisphenol F solution (10 mg / L). First, let it stand for 30 min under dark conditions. After reaching the adsorption equilibrium, turn on the ultrasonic reactor (US = 120 W). At this time, add persulfate, and after mixing evenly, obtain the MoS2 / h-BN composite piezoelectric catalyst-activated persulfate system under ultrasonic conditions. Among them, the mass ratio of MoS2 / h-BN to bisphenol F is 20:1, and the mass ratio of MoS2 / h-BN to persulfate is 10:46.11.

[0066] Example 4

[0067] The preparation method of the MoS2 / h-BN composite piezoelectric catalyst in this example includes the following steps:

[0068] (1) Dissolve thiourea and sodium molybdate dihydrate in a mass ratio of 3:4 (0.9 g, 1.2 g) in 90 mL of ultrapure water, adjust the pH = 1 with hydrochloric acid, and place it in a polytetrafluoroethylene inner liner at a temperature of 160 °C for organic synthesis for 24 h;

[0069] (2) Filter, wash the hydrothermal product to neutrality and dry it to obtain MoS2NFs powder. Among them, the pore size of the filter membrane for filtration is 0.22 μm, and the drying temperature is 60 °C;

[0070] (3) Dissolve urea and boric acid in a molar ratio of 1:40 (1 mol, 40 mol) in 40 mL of ultrapure water, heat the mixed solution at 65 °C for organic synthesis to produce a white solid, and perform high-temperature calcination in a nitrogen atmosphere. Heat it to 900 °C at a rate of 4 °C / min and calcine for 5 h, then grind to obtain h-BN powder;

[0071] (4) Mix MoS₂ and h-BN with a mass ratio of 9:1 (90 mg, 10 mg) in 30 mL of ultrapure water and stir for 8 h. Centrifuge, wash, and dry the resulting homogeneous suspension to obtain the product MoS₂ / h-BN composite piezoelectric catalyst, denoted as MoS₂ / 0.10BN;

[0072] The MoS₂ / h-BN composite piezoelectric catalyst obtained by the above preparation method can be applied to degrade bisphenol F in water, and the steps are as follows:

[0073] Take 10 mg of MoS₂ / h-BN composite piezoelectric catalyst and place it in 50 mL of bisphenol F solution (10 mg / L). First, let it stand for 30 min under dark conditions. After reaching the adsorption equilibrium, turn on the ultrasonic reactor (US = 120 W). At this time, add persulfate. After mixing evenly, obtain the MoS₂ / h-BN composite piezoelectric catalyst-activated persulfate system under ultrasonic conditions. Among them, the mass ratio of MoS₂ / h-BN to bisphenol F is 20:1, and the mass ratio of MoS₂ / h-BN to persulfate is 10:46.11.

[0074] Example 5

[0075] The preparation method of the MoS₂ / h-BN composite piezoelectric catalyst in this example includes the following steps:

[0076] (1) Dissolve thiourea and sodium molybdate dihydrate in 90 mL of ultrapure water according to a mass ratio of 3:4 (0.9 g, 1.2 g). Adjust the pH = 1 with hydrochloric acid, and place it in a polytetrafluoroethylene inner liner at a temperature of 180 °C for organic synthesis for 24 h;

[0077] (2) Filter, wash the hydrothermal product to neutrality, and dry it to obtain MoS₂NFs powder. Among them, the pore size of the filter membrane for filtration is 0.22 μm, and the drying temperature is 60 °C;

[0078] (3) Dissolve urea and boric acid in 40 mL of ultrapure water according to a molar ratio of 1:40 (1 mol, 40 mol). Heat the mixed solution at 65 °C for organic synthesis to produce a white solid. Calcinate it in a nitrogen atmosphere by heating to 900 °C at a rate of 4 °C / min for 5 h, and grind it to obtain h-BN powder;

[0079] (4) Mix MoS₂ and h-BN with a mass ratio of 1:1 (50 mg, 50 mg) in 30 mL of ultrapure water and stir for 8 h. Centrifuge, wash, and dry the resulting homogeneous suspension to obtain the product MoS₂ / h-BN composite piezoelectric catalyst, denoted as MoS₂ / 0.50BN;

[0080] The MoS₂ / h-BN composite piezoelectric catalyst obtained by the above preparation method can be applied to degrade bisphenol F in water, and the steps are as follows:

[0081] Take the MoS2 / h-BN composite piezoelectric catalyst and place it in 50 mL of bisphenol F solution (10 mg / L). First, let it stand still for 30 min under dark conditions. After reaching the adsorption equilibrium, turn on the ultrasonic reactor (US = 120 W). At this time, add peroxymonosulfate. After mixing evenly, obtain the ultrasonic condition MoS2 / h-BN composite piezoelectric catalyst-activated peroxymonosulfate system. Among them, the mass ratio of MoS2 / h-BN to bisphenol F is 20:1, and the mass ratio of MoS2 / h-BN to peroxymonosulfate is 10:46.11.

[0082] Comparative Example 1

[0083] In this comparative example, MoS2NFs was used as the piezoelectric catalyst, and other raw materials, ratios, preparation methods, and detection methods were the same as those in Example 1. The removal rate of bisphenol F reached 59.2% in 30 min.

[0084] Figure 5 This is the comparative diagram of the effects of different materials prepared by the present invention on activating PMS to degrade 10 mg / L bisphenol F under ultrasonic conditions. Among them, MoS2 / 0.02BN, MoS2 / 0.05BN, MoS2 / 0.10BN, MoS2 / 0.20BN, and MoS2 / 0.50BN respectively represent the mass ratio of MoS2 to h-BN as 98:2, 95:5, 9:1, 4:1, and 1:1;

[0085] As can be seen from the figure, the removal rates of bisphenol F by piezoelectric degradation for 30 min of MoS2, MoS2 / 0.02BN, MoS2 / 0.05BN, MoS2 / 0.10BN, MoS2 / 0.20BN, and MoS2 / 0.50BN are 59.2%, 68.7%, 63.6%, 68.0%, 84.2%, and 56.8% respectively.

[0086] It can be seen that the degradation effect of MoS2 / 0.20BN is the best.

[0087] Figure 6 This is the comparative diagram of the reaction kinetic constants of different materials prepared by the present invention on activating PMS to degrade 10 mg / L bisphenol F under ultrasonic conditions. As can be seen from the figure, the reaction kinetic constants of the removal rates of bisphenol F by piezoelectric degradation for 30 min of MoS2, MoS2 / 0.02BN, MoS2 / 0.05BN, MoS2 / 0.10BN, MoS2 / 0.20BN, and MoS2 / 0.50BN are 0.027, 0.039, 0.032, 0.038, 0.055, and 0.028 respectively.

[0088] It can be seen that the degradation rate of MoS2 / 0.20BN is the fastest.

[0089] By comparing Comparative Example 1 with Example 1, the removal rate of bisphenol F degraded by MoS2 under ultrasound is lower than the scope of the present invention.

[0090] In summary, the present invention provides a preparation method of MoS2 / h-BN composite piezoelectric catalyst, which can efficiently catalytically degrade bisphenol F in water, can efficiently degrade bisphenol F, a new and difficult-to-degrade pollutant, and has a high degradation efficiency. The piezoelectric catalyst of the present invention can activate persulfate under ultrasound, and compared with the traditional ultraviolet light activation of persulfate, it has low energy consumption and low cost.

[0091] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the present invention.

Claims

1. A preparation method of a MoS2 / h-BN composite piezoelectric catalyst, characterized in that: include, Mixing and dissolving thiourea and sodium molybdate dihydrate in water, adding hydrochloric acid to adjust the pH, and heating to obtain a hydrothermal product, wherein the mass ratio of thiourea to sodium molybdate dihydrate is 3:4-10, the pH value is 1, the heating temperature is 180-200° C., and the reaction time is 20-24 hours; The hydrothermal product is filtered, washed to neutrality, and dried to obtain MoS2NFs powder, wherein the pore size of the filter membrane used in the filtration is 0.22-0.45 μm, the drying temperature is 50-70° C., the drying type is vacuum drying, and the MoS2NFs powder presents a nanoflower shape; Dissolving urea and boric acid in ultrapure water, heating to produce a white solid, calcining at high temperature, and grinding to obtain h-BN powder, wherein the molar ratio of urea to boric acid is 1:40-50; MoS2 NFs and h-BN were added to ultrapure water and mixed, and the mixture was centrifuged, washed and dried to obtain the product MoS2 / h-BN composite piezoelectric catalyst, wherein the mass ratio of MoS2 to h-BN was 4:1, and the mixing time was 8-12 h.

2. The preparation method according to claim 1, characterized in that: The heating produces a white solid, which is calcined at a high temperature, wherein the heating temperature is 60-70° C. The high-temperature calcination is carried out in a nitrogen atmosphere at a temperature of 800-1000° C. and the calcination time is 4-6 hours.

3. The preparation method according to claim 1, characterized in that: The centrifugal speed is 8000~9000 r / min, and the centrifugal time is 4~6min.

4. The MoS2 / h-BN composite piezoelectric catalyst prepared by the preparation method described in any one of claims 1 to 3.

5. Use of the composite piezoelectric catalyst according to claim 4 for degrading bisphenol F in water, characterized in that: include, Adding MoS2 / h-BN composite piezoelectric catalyst into bisphenol F solution; Add peroxymonosulfate to carry out piezoelectric catalytic reaction; Wherein, the mass ratio of the piezoelectric catalyst to bisphenol F is 20-100:1, and the mass ratio of the piezoelectric catalyst to peroxymonosulfate is 25:10-60.78.

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