A piezoelectric composite material for enhancing nano-enzyme activity, a preparation method thereof, and an antibacterial application thereof

Abstract

The application belongs to the technical field of biomedical materials, and relates to a piezoelectric enhanced nanometer enzyme activity composite material and a preparation method and antibacterial application thereof, wherein cobalt doped molybdenum disulfide is grown in situ on the surface of bismuth titanate nanosheet to obtain a BTO@Co-MoS2 composite material. The composite material produces a piezoelectric effect under pressure stimulation, and under the action of a built-in electric field of BTO@Co-MoS2 interfaces, electrons promote the self-circulation of a molybdenum disulfide redox pair, and thus the catalytic activity of a halogen-like peroxidase is improved; meanwhile, the generation of piezoelectric catalytic hydrogen peroxide improves the problem of insufficient endogenous hydrogen peroxide. The piezoelectric enhanced nanometer enzyme activity composite material prepared by the application can achieve a sterilization rate of 98.39% and 99.95% on staphylococcus aureus and escherichia coli in antibacterial application.

Description

Technical Field

[0001] This invention belongs to the field of biomedical materials technology, and relates to a piezoelectrically enhanced nanoenzyme composite material, its preparation method and antibacterial application. Background Technology

[0002] The rising morbidity and mortality rates caused by bacterial infections pose a significant global health threat, with over 13 million people dying from infectious diseases worldwide each year. On the one hand, the widespread use of antibiotics has screened out multidrug-resistant microorganisms carrying heritable resistance genes; on the other hand, biofilm formation allows even susceptible strains to acquire phenotypic high levels of resistance, which can be 10-1000 times higher than in the planktonic state. Both factors combined make the treatment of clinical infections extremely difficult.

[0003] In natural environments, some marine algae (such as coral algae and yellow caustic solanacearum) secrete natural halogen peroxidases (HPOs) containing iron or vanadium, which can effectively catalyze the oxidation of halogenated compounds by hydrogen peroxide (H2O2) into hypohalous acids with antibacterial activity. Inspired by this, artificial enzyme mimics with stable chemical structures have been proposed as potential alternatives to natural enzymes. Among them, nanozymes, as a class of enzyme-like catalytic nanomaterials that follow enzyme kinetics under physiologically relevant conditions and possess enzyme catalytic activity, have been widely used in recent years for biomimetic chemical research that mimics proteases, etc., due to their high efficiency, tunable activity, ease of scalability, and recyclability.

[0004] MoS2 nanozymes exhibit halogen-like peroxidase activity, which occurs through the reaction of H2O2 with Br. - Hypobromic acid is formed, and its highly active coordinated unsaturated Mo atoms and sulfur vacancies can effectively kill bacteria. Further research shows that Co doping can replace some Mo sites, increasing sulfur vacancies and yielding Co-MoS2 with high enzyme activity. However, traditional nanozymes are limited by insufficient endogenous hydrogen peroxide, resulting in low activity. The piezoelectric effect can promote the valence state transformation of metal elements in nanozymes, thereby improving nanozyme activity. Simultaneously, the piezoelectric effect can promote hydrogen peroxide generation, increasing the substrate for enzyme reactions, thus enhancing nanozyme activity.

[0005] Piezoelectric materials generate piezoelectric potentials under mechanical force, which can promote electron-hole separation and have been used to enhance catalytic reactions. However, there are currently no reports of combining the piezoelectric effect with nanozyme systems to address the problem of insufficient endogenous hydrogen peroxide.

[0006] Therefore, developing a nanoenzyme composite material that can overcome the deficiency of endogenous hydrogen peroxide by utilizing the piezoelectric effect and achieve highly efficient antibacterial properties has significant scientific value and application prospects. Summary of the Invention

[0007] Bismuth titanate (Bi4Ti3O)12 Bismuth titanate (BTO) is a bioactive inorganic piezoelectric material with excellent piezoelectric properties due to its asymmetric crystal structure. Bismuth titanate and molybdenum disulfide have matched energy level structures; the piezoelectric effect promotes electron transfer to molybdenum disulfide, enhancing its enzyme activity, while piezoelectric holes promote hydrogen peroxide generation. By combining bismuth titanate with cobalt-doped molybdenum disulfide, a piezoelectrically enhanced nanoenzyme system can be constructed, which can be used for highly efficient antibacterial applications.

[0008] In view of this, the present invention provides a composite material with piezoelectric enhancement of nanozyme activity, its preparation method and antibacterial application. By growing cobalt-doped molybdenum disulfide in situ on the surface of bismuth titanate nanosheets, a composite material containing heterojunction is formed, which achieves highly efficient antibacterial activity against Staphylococcus aureus and Escherichia coli.

[0009] To achieve the above objectives, the present invention provides the following technical solution: The first aspect of the present invention provides a composite material for piezoelectrically enhanced nanozyme activity, wherein the composite material is a composite material containing a heterojunction formed by in-situ growth of cobalt-doped molybdenum disulfide on bismuth titanate nanosheets, denoted as BTO@Co-MoS2.

[0010] Preferably, the composite material generates a microcurrent under pressure stimulation, promoting the transfer of electrons from bismuth titanate to cobalt-doped molybdenum disulfide, while holes catalyze the generation of hydrogen peroxide from water.

[0011] A second aspect of the present invention provides a method for preparing the above-mentioned piezoelectrically enhanced nanozyme activity composite material, comprising the following steps: (1) Preparation of bismuth titanate nanosheets; (2) Thiourea, ammonium molybdate, cobalt acetate hexahydrate and bismuth titanate nanosheets were dispersed in water and reacted to grow cobalt-doped molybdenum disulfide in situ on the surface of bismuth titanate nanosheets to obtain BTO@Co-MoS2 composite material.

[0012] Preferably, the method for preparing the bismuth titanate nanosheets is as follows: sodium chloride, potassium chloride, titanium dioxide and bismuth trioxide are thoroughly ground and mixed in a molar ratio of 60-65:60-65:5-10:3-8. The resulting mixed powder is calcined in a muffle furnace at 500-800℃ for 1-2 hours with a programmed temperature rise. The product is washed with anhydrous ethanol and ultrapure water and dried at 50-80℃ for 10-14 hours to obtain bismuth titanate nanosheets.

[0013] Preferably, the mass ratio of thiourea, ammonium molybdate, cobalt acetate hexahydrate, and bismuth titanate is 100-300:100-300:1-30:10-50.

[0014] Preferably, the reaction in step (2) is carried out at 150-200 °C for 8-12 hours.

[0015] Preferably, after the reaction in step (2) is completed, the product is cooled naturally, washed with anhydrous ethanol and ultrapure water respectively, and dried at 50-80°C for 10-14 hours.

[0016] A third aspect of the present invention provides the application of the above-mentioned BTO@Co-MoS2 composite material in the preparation of antibacterial materials.

[0017] Preferably, the application method is as follows: BTO@Co-MoS2, hydrogen peroxide, sodium bromide, and bacteria are co-incubated in a shaker for 1-4 hours. The number of surviving bacteria is calculated using the plate coating method, and the sterilization rate is calculated as follows: Sterilization rate = (number of colonies in the blank control group - number of surviving colonies) / number of colonies in the blank control group. 100%.

[0018] Preferably, the shaker is set to a rotation speed of 150 rpm for a total incubation time of 2 hours.

[0019] Preferably, the antibacterial material is used to kill Staphylococcus aureus and / or Escherichia coli.

[0020] A fourth aspect of the present invention provides an antibacterial composition comprising the aforementioned BTO@Co-MoS2 composite material, hydrogen peroxide, and sodium bromide.

[0021] Preferably, the concentration of BTO@Co-MoS2 composite material in the antibacterial composition is 0.1-0.5 mg / mL, the concentration of hydrogen peroxide is 0.5-1 mM, and the concentration of sodium bromide is 10-50 mM.

[0022] The advantages and beneficial effects of this invention are: (1) This invention successfully constructed Co-MoS2 with more exposed active sites through Co doping engineering. By doping with metal ions, more defects are created, more edge active sites are exposed, and the catalytic activity of nanozymes is improved.

[0023] (2) This invention obtains a heterojunction structure (BTO@Co-MoS2) by in-situ growing Co-MoS2 composite material on the surface of bismuth titanate (BTO) nanosheets. Under external stimulation (pressure), the heterojunction structure causes electrons and holes to separate. Holes can directly catalyze the formation of hydrogen peroxide from water, increasing the concentration of substrate for nanozyme catalysis. At the same time, electrons can promote the self-circulation of redox pairs in nanozymes, enhancing the catalytic efficiency of nanozymes. Through the synergistic effect of piezoelectricity and enzyme catalytic activity, the overall performance of the composite material is significantly improved.

[0024] (3) The piezoelectrically enhanced nanozyme activity composite material prepared by the present invention can be applied to antibacterial applications and can achieve a bactericidal rate of 98.39% and 99.95% against Staphylococcus aureus and Escherichia coli, respectively. Attached Figure Description

[0025] Figure 1 The results show the characterization of the BTO nanosheets of Example 1 using scanning electron microscopy.

[0026] Figure 2 The results are from the characterization of the BTO@Co-MoS2 composite material of Example 3 using scanning electron microscopy.

[0027] Figure 3 The current output characteristics of BTO nanosheets in Example 1, BTO@MoS2 in Comparative Example 3, and BTO@Co-MoS2 composite material in Example 3 under cyclic intermittent pressure are tested.

[0028] Figure 4 The results are the test results of the hydrogen peroxide production capacity of BTO in Example 1 of the present invention.

[0029] Figure 5 The absorbance curves for the phenol red color change test of the BTO composite material of Example 1, MoS2 of Comparative Example 1, Co-MoS2 of Comparative Example 2, BTO@MoS2 of Comparative Example 3, and BTO@Co-MoS2 composite material of Example 3 are shown.

[0030] Figure 6 The images show the phenol red color change catalyzed by the composite materials of BTO in Example 1, MoS2 in Comparative Example 1, Co-MoS2 in Comparative Example 2, BTO@MoS2 in Comparative Example 3, and BTO@Co-MoS2 in Example 3. Figure 7 This is a schematic diagram showing the in vitro antibacterial performance results of different samples and under different culture conditions according to the present invention. Detailed Implementation

[0031] The specific embodiments of the present invention will be described in further detail below with reference to the examples. These examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0032] Example 1 A method for preparing bismuth titanate nanosheets, comprising: 60 mmol of sodium chloride and 60 mmol of potassium chloride were thoroughly ground for 5 minutes, then 5 mmol of titanium dioxide and 3 mmol of bismuth trioxide were added and thoroughly ground for 60 minutes. The mixed powder was calcined in a muffle furnace at 500°C for 1 hour with a programmed temperature rise. The product was washed three times with anhydrous ethanol and ultrapure water, respectively, and dried at 50°C for 10 hours to obtain bismuth titanate (BTO) nanosheets.

[0033] Example 2 A method for preparing bismuth titanate nanosheets, comprising: 65 mmol of sodium chloride and 65 mmol of potassium chloride were thoroughly ground for 20 minutes, then 10 mmol of titanium dioxide and 8 mmol of bismuth trioxide were added and thoroughly ground for 120 minutes. The mixed powder was calcined in a muffle furnace at 800 °C for 2 hours with a programmed temperature rise. The product was washed three times with anhydrous ethanol and ultrapure water, and dried at 80 °C for 14 hours to obtain bismuth titanate (BTO) nanosheets.

[0034] Example 3 A method for preparing BTO@Co-MoS2 composite material, comprising: 100 mg of thiourea and 100 mg of ammonium molybdate were dissolved in 10 mL of ultrapure water, and then 1 mg of cobalt acetate hexahydrate was added. After dissolution, 10 mg of bismuth titanate (BTO) nanosheets from Example 1 were added. The final solution was transferred to a high-pressure reactor and reacted at 150 °C for 8 hours. After the reaction was completed, the mixture was allowed to cool naturally. The product was washed three times with anhydrous ethanol and ultrapure water, and then dried at 50 °C for 10 hours to obtain the BTO@Co-MoS2 composite material.

[0035] Example 4 A method for preparing BTO@Co-MoS2 composite material, comprising: 300 mg of thiourea and 300 mg of ammonium molybdate were dissolved in 30 mL of ultrapure water, and then 30 mg of cobalt acetate hexahydrate was added. After dissolving, 50 mg of bismuth titanate nanosheets from Example 2 were added. The final solution was transferred to a high-pressure reactor and reacted at 200 °C for 12 hours. After the reaction was completed, the mixture was allowed to cool naturally. The product was washed three times with anhydrous ethanol and ultrapure water, and then dried at 80 °C for 14 hours to obtain the BTO@Co-MoS2 composite material.

[0036] Comparative Example 1 Methods for preparing pure MoS2 include: 100 mg of thiourea and 100 mg of ammonium molybdate were dissolved in 10 mL of ultrapure water. After dissolution, the solution was transferred to a high-pressure reactor and reacted at 150 °C for 8 hours. After the reaction was completed, the solution was allowed to cool naturally. The product was washed three times with anhydrous ethanol and ultrapure water, respectively, and dried at 50 °C for 10 hours to obtain pure MoS2.

[0037] Comparative Example 2 The preparation method of Co-MoS2 (BTO-free) includes: 100 mg of thiourea and 100 mg of ammonium molybdate were dissolved in 10 mL of ultrapure water, and then 1 mg of cobalt acetate hexahydrate was added. After dissolution, the solution was transferred to a high-pressure reactor and reacted at 150 °C for 8 hours. After the reaction was completed, the solution was allowed to cool naturally. The product was washed three times with anhydrous ethanol and ultrapure water, and then dried at 50 °C for 10 hours to obtain Co-MoS2 (BTO-free).

[0038] Comparative Example 3 Methods for preparing BTO@MoS2 (without Co doping) include: 300 mg of thiourea and 300 mg of ammonium molybdate were dissolved in 30 mL of ultrapure water. After dissolution, 50 mg of bismuth titanate nanosheets from Example 1 were added. The final solution was transferred to a high-pressure reactor and reacted at 200 °C for 12 hours. After the reaction was completed, the mixture was allowed to cool naturally. The product was washed three times with anhydrous ethanol and ultrapure water, respectively, and dried at 80 °C for 14 hours to obtain BTO@MoS2 (without Co doping).

[0039] The piezoelectrically enhanced nanozyme composite material BTO@Co-MoS2 prepared in Examples 3 and 4 of this invention can be used in antibacterial applications. Successful Co doping resulted in Co-MoS2 with more exposed active sites. Doping with metal ions created more defects and exposed more edge active sites, thereby improving the catalytic activity of the nanozyme.

[0040] This invention forms a heterojunction structure (BTO@Co-MoS2) composite material by in-situ growth of Co-MoS2 on the surface of bismuth titanate (BTO) nanosheets. Under external stimulation, the heterojunction structure allows electrons and holes to separate. Holes can directly catalyze the formation of hydrogen peroxide from water, increasing the concentration of substrate for nanozyme catalysis. At the same time, electrons can promote the self-circulation of redox pairs in nanozymes, enhancing the catalytic efficiency of nanozymes.

[0041] The BTO nanosheets of Example 1 and the BTO@Co-MoS2 composite material of Example 3 were characterized using scanning electron microscopy. The results are as follows: Figure 1 and Figure 2 As shown, the BTO nanosheets in Example 1 are square sheet structures with uniform shape, a side length of about 500 nm, and a thickness of about 20 nm. The nanosheets of the BTO@Co-MoS2 composite material in Example 3 have a large number of rough wrinkles on their surface, indicating that Co-MoS2 was grown in situ on the surface of the BTO nanosheets.

[0042] To detect the electrical output of the composite material under mechanical stimulation, a saturated silver chloride electrode was used as the reference electrode, a platinum wire electrode as the counter electrode, and a 2 mg / mL aqueous solution of BTO@Co-MoS2 was added dropwise onto a glassy carbon electrode as the working electrode, forming a three-electrode system. The test was conducted in 10.0 mL of carbonate buffer solution. The output short-circuit current was then recorded using an electrochemical workstation (660e, Chenhua, China) under intermittent pressure cycling at 200 rpm (cycle: 30 seconds of stirring to provide mechanical pressure, 30 seconds of turning off mechanical pressure). The test results are as follows: Figure 3 As shown. The piezoelectric response properties of the BTO nanosheets of Example 1, the BTO@MoS2 composite material of Comparative Example 3, and the BTO@Co-MoS2 composite material of Example 3 were evaluated by the short-circuit current output under cyclic intermittent pressure. It can be seen that when the BTO nanosheets are subjected to compressive stress caused by the collapse of cavitation bubbles, the lattice of the piezoelectric phase deforms, the internal dipole direction deflects, electrons and holes separate, and free electrons will flow through the external circuit to generate current; when the external force is removed, the current disappears. From Figure 3 As can be seen from the data, the BTO@Co-MoS2 composite material in Example 3 has a large output current, indicating that it has a good piezoelectric effect.

[0043] To test the hydrogen peroxide production capacity of BTO materials, an iodine colorimetric reaction was used. The BTO nanosheets of Example 1, the BTO@MoS2 composite material of Comparative Example 3, and the BTO@Co-MoS2 composite material of Example 3 were ultrasonicated for 1 hour at a power of 200 W and a frequency of 40 kHz. After centrifugation, 500 μL of the supernatant was taken, and 50 μL of 0.1 M ammonium molybdate and 2 mL of 0.1 M potassium iodide were added. The reaction was allowed to proceed for 10 minutes, and the absorbance change at 352 nm was measured. Using the absorbance change of water as a standard curve, the hydrogen peroxide production was calculated. Figure 4 As shown, the hydrogen peroxide production capacity of BTO nanosheets is 200 μmol / g. -1 ·h -1 The difference is much greater than that of Comparative Example 3 and Example 3, indicating that it has a good hydrogen peroxide production capacity. This shows that BTO is the main contributor to hydrogen peroxide production. The hydrogen peroxide production capacity decreases after loading with MoS2 or Co-MoS2, and the hydrogen peroxide is rapidly decomposed by MoS2 or Co-MoS2 with halogen-like peroxidase activity.

[0044] The enzyme catalytic performance of the piezoelectrically enhanced nanozyme composite material, specifically the ability of the BTO@Co-MoS2 composite material to catalyze the production of hypobromic acid from hydrogen peroxide, was verified using a phenol red color change experiment. 0.25 mg / mL of BTO from Example 1, MoS2 from Comparative Example 1, Co-MoS2 from Comparative Example 2, BTO@MoS2 from Comparative Example 3, and BTO@Co-MoS2 from Example 3 were mixed with 1 mM hydrogen peroxide, 10 mM sodium bromide, and 50 μM phenol red, respectively. The mixture was stirred continuously at room temperature, and the absorbance of the phenol red solution was recorded every two hours. Figure 5 and Figure 6 As shown, within the same reaction time, BTO and MoS2 exhibited high absorbance at 430 nm and almost no absorbance at 590 nm, displaying the original yellow color of the phenol red solution. The absorbance of the Co-MoS2, BTO@MoS2, and BTO@Co-MoS2 composites decreased at 430 nm and increased at 590 nm, causing the phenol red solution to turn blue-violet. BTO@Co-MoS2 showed the highest absorbance at 590 nm, completely turning the phenol red solution blue-violet. This phenomenon indicates that the BTO@Co-MoS2 composite produced the most hypobromic acid within the same reaction time, demonstrating its strongest halogen-like peroxidase activity.

[0045] Antibacterial performance testing of composite materials with piezoelectrically enhanced nanozyme activity: Gram-negative bacteria *Escherichia coli* (E. coli) and Gram-positive bacteria *Staphylococcus aureus* (S. aureus) were selected for testing, respectively. The viable bacterial concentration in the bacterial suspension was 10-1. 6 CFU / mL.

[0046] The experiment consisted of four groups: 1. Blank control group: 0.1 mL bacterial suspension + 0.9 mL sterile water; 2. Hydrogen peroxide and sodium bromide group: 0.1 mL bacterial culture + 0.1 mL 1 mM hydrogen peroxide + 0.1 mL 100 mM sodium bromide + 0.7 mL sterile water; 3. BTO@Co-MoS2 composite material group: 0.1 mL bacterial solution + 0.1 mL of 2.5 mg / mL BTO@Co-MoS2 composite material aqueous solution prepared in Example 3 + 0.8 mL sterile water; 4. BTO@Co-MoS2 composite material, hydrogen peroxide and sodium bromide group: 0.1 mL bacterial solution + 0.1 mL 2.5 mg / mL aqueous solution of BTO@Co-MoS2 composite material prepared in Example 3 + 0.1 mL 1 mM hydrogen peroxide + 0.1 mL 100 mM sodium bromide + 0.6 mL sterile water.

[0047] All groups were incubated in a shaker (150 rpm) for 2 hours. The number of surviving bacteria was calculated using the plate spread method, and the sterilization rate was calculated as follows: Sterilization rate = (number of colonies in the blank control group - number of surviving colonies) / number of colonies in the blank control group. 100%. The sterilization rate test data are shown in Table 1.

[0048] like Figure 7 As shown, the blank control group was teeming with bacteria, while the hydrogen peroxide and sodium bromide groups exhibited very weak bactericidal effects. The BTO@Co-MoS2 composite material itself showed almost no bactericidal effect. However, under the conditions of 1 mM hydrogen peroxide and 10 mM sodium bromide, the BTO@Co-MoS2 composite material could decompose hydrogen peroxide to produce hypobromoic acid, which had a good bactericidal effect; as shown in the figure, only a few bacteria survived. The bactericidal rate against Staphylococcus aureus reached 98.39%, and the bactericidal rate against Escherichia coli was as high as 99.95%. This indicates that the piezoelectrically enhanced nanoenzyme activity nanocomposite material BTO@Co-MoS2 prepared in this invention has good antibacterial application potential.

[0049] Table 1

[0050] The antibacterial properties of the materials prepared in Examples 1-2, 4, and Comparative Examples 1-3 were tested. Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) were selected to prepare 10... 6 A CFU / mL bacterial suspension was prepared by adding 0.1 mL of the bacterial suspension, 0.1 mL of a 2.5 mg / mL composite material aqueous solution, 0.1 mL of 1 mM hydrogen peroxide, and 0.1 mL of 100 mM sodium bromide. The mixture was incubated in a shaker (150 rpm) for 2 hours. The number of surviving bacteria was calculated using the plate plating method to determine the sterilization rate. Sterilization rate = (Number of colonies in the blank control group - Number of surviving colonies) / Number of colonies in the blank control group. 100%. The results are shown in Table 2.

[0051] Table 2

[0052] As shown in Table 2, the BTO@Co-MoS2 composite materials prepared in Examples 3 and 4 achieved a bactericidal rate of over 98% against Escherichia coli and Staphylococcus aureus, which is much higher than that of Comparative Examples 1-3. This indicates that cobalt doping and BTO composite have a synergistic promoting effect on enhancing the antibacterial activity of nanozymes.

[0053] The above are merely preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be considered as limitations on the present invention, and the scope of protection of the present invention should be determined by the scope defined in the claims. For those skilled in the art, several improvements and modifications can be made without departing from the spirit and scope of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A piezoelectrically enhanced nanoenzyme activity composite material, characterized in that, The composite material is a composite material containing heterojunction formed by in-situ growth of cobalt-doped molybdenum disulfide on the surface of bismuth titanate nanosheets. Its preparation method includes the following steps: (1) Sodium chloride, potassium chloride, titanium dioxide and bismuth trioxide are ground and mixed. The resulting mixed powder is calcined in a muffle furnace at 500-800℃ for 1-2 hours, and then washed and dried to obtain bismuth titanate nanosheets. (2) Thiourea, ammonium molybdate, cobalt acetate hexahydrate and bismuth titanate nanosheets are dispersed in water and reacted to grow cobalt-doped molybdenum disulfide in situ on the surface of bismuth titanate nanosheets to obtain BTO@Co-MoS2 composite material. The mass ratio of thiourea, ammonium molybdate, cobalt acetate hexahydrate and bismuth titanate nanosheets is 100-300:100-300:1-30:10-50.

2. The composite material according to claim 1, characterized in that, The reaction described in step (2) is carried out at 150-200 °C for 8-12 hours.

3. The composite material according to claim 1, characterized in that, After the reaction in step (2) is completed, the product is cooled naturally, washed with anhydrous ethanol and ultrapure water respectively, and dried at 50-80℃ for 10-14 hours.

4. A method for preparing a piezoelectrically enhanced nanozyme activity composite material as described in any one of claims 1-3, characterized in that, Includes the following steps: (1) Sodium chloride, potassium chloride, titanium dioxide and bismuth trioxide are ground and mixed. The resulting mixed powder is calcined in a muffle furnace at 500-800℃ for 1-2 hours, and then washed and dried to obtain bismuth titanate nanosheets. (2) Thiourea, ammonium molybdate, cobalt acetate hexahydrate and bismuth titanate nanosheets are dispersed in water and reacted to grow cobalt-doped molybdenum disulfide in situ on the surface of bismuth titanate nanosheets to obtain BTO@Co-MoS2 composite material. The mass ratio of thiourea, ammonium molybdate, cobalt acetate hexahydrate and bismuth titanate nanosheets is 100-300:100-300:1-30:10-50.

5. The preparation method according to claim 4, characterized in that, The reaction described in step (2) is carried out at 150-200 °C for 8-12 hours.

6. The preparation method according to claim 4, characterized in that, After the reaction in step (2) is completed, the product is cooled naturally, washed with anhydrous ethanol and ultrapure water respectively, and dried at 50-80℃ for 10-14 hours.

7. The application of a piezoelectrically enhanced nanozyme activity composite material as described in claim 1 in the preparation of antibacterial materials, characterized in that, The antibacterial material is used to kill Staphylococcus aureus or Escherichia coli.

8. An antibacterial composition, characterized in that, It includes the composite material as described in any one of claims 1-3, as well as hydrogen peroxide and sodium bromide.

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