Enzyme-like hydrogen peroxide sensor based on layered phosphorus acid compound and method for preparing the same

Abstract

This invention provides an enzyme-like hydrogen peroxide sensor based on layered phosphate compounds and its preparation method. A printed electrode with a metal layer on its surface is prepared and used as the working electrode. This electrode, along with a reference electrode and a counter electrode, is immersed in a phosphate compound solution to form a connected three-electrode system. A voltage is applied, and the system operates at a specific temperature for a certain time to obtain a printed electrode with layered phosphate compounds on its surface. After cleaning and drying, the enzyme-like hydrogen peroxide sensor based on layered phosphate compounds is obtained. This invention uses phosphate compounds instead of enzymes to prepare the hydrogen peroxide sensor under enzyme-free conditions, avoiding the problems of difficult enzyme immobilization and easy inactivation leading to unstable sensor properties in existing technologies. Furthermore, the metal-phosphate compound layered structure increases the specific surface area and the number of reactive sites, improving the sensor sensitivity. Compared with traditional enzyme-like sensor preparation methods, this method is rapid, simple, and low-cost, with promising market application prospects.

Description

Technical Field

[0001] This invention relates to the field of hydrogen peroxide sensor technology, and in particular to an enzyme-like hydrogen peroxide sensor based on layered phosphate compounds and its preparation method. Background Technology

[0002] Hydrogen peroxide (H2O2) can inhibit microbial growth and has disinfection and sterilization effects, thus it is widely used in the food industry. However, excessive H2O2 in food can cause many adverse effects on humans, such as cardiovascular disease, serious gastrointestinal problems, and neurological disorders. Therefore, the detection of hydrogen peroxide in food is particularly important. Existing electrochemical sensors for detecting hydrogen peroxide are divided into two categories: enzyme-loaded and enzyme-free. Enzyme-loaded electrochemical biosensors have disadvantages such as difficulty in enzyme immobilization, easy detachment, high cost, and easy inactivation.

[0003] Chinese invention patent (application number CN 202210478346.7) discloses a hydrogen peroxide electrochemical sensor based on a covalent organic framework-multi-walled carbon nanotube. First, a covalent organic framework-multi-walled carbon nanotube composite material is prepared by in-situ growth, and then coated onto an electrode to form a working electrode for constructing the hydrogen peroxide electrochemical sensor. However, the trimethylbenzene used in the preparation process is toxic, flammable, and explosive, making mass production difficult. Invention patent (application number CN202010414876.6) discloses a method for preparing an AuNWs@PB nanocomposite material and a modified electrode. This method involves in-situ growth of Prussian blue nanoparticles on the surface of gold nanowires to form an AuNWs@PB nanocomposite material, which is then modified onto a glassy carbon electrode to obtain an enzyme-like hydrogen peroxide electrochemical sensor. However, this method directly drops the AuNWs@PB solution onto the polished glassy carbon electrode surface, which is prone to detachment, resulting in unstable sensor properties. An invention patent (application number CN 201610073770.8) discloses a gold nanoarray electrode and its fabricated enzyme-free hydrogen peroxide sensor. The method involves preparing a silicon-based monolayer polymer colloidal crystal array. Using this array as a template, a gold film is deposited on the template surface using physical deposition. Thermal decomposition and annealing are then performed to remove the monolayer polymer colloidal crystal array, yielding a silicon-based gold nanoarray. This array is then directly used as a gold nanoarray electrode for hydrogen peroxide detection. However, this method suffers from drawbacks such as the small size of the nanoparticles, their tendency to aggregate, instability, and the cumbersome preparation process.

[0004] In view of this, it is necessary to design an improved enzyme-like hydrogen peroxide sensor based on layered phosphate compounds and its preparation method to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide an enzyme-like hydrogen peroxide sensor based on layered phosphate compounds and its preparation method. The method involves first introducing a metal layer onto the surface of a printed electrode, and then electropolymerizing it to coat the surface with layered phosphate compounds, thus obtaining an enzyme-like hydrogen peroxide sensor. Compared with existing enzyme-like sensor preparation methods, this method eliminates the need for organic polymers, directly producing a sensor with a surface-loaded two-dimensional layered phosphate compound. This method is simple, has a short preparation cycle, and is less expensive than existing enzyme-free sensors. Furthermore, this enzyme-like hydrogen peroxide sensor has multiple reactive sites and high sensitivity for hydrogen peroxide detection, making it highly promising for market applications.

[0006] To achieve the above-mentioned objective, this invention provides a method for preparing an enzyme-like hydrogen peroxide sensor based on layered phosphate compounds, comprising the following steps:

[0007] S1. Introduce a metal layer on the surface of a conductive material to obtain a printed electrode with a metal layer on the surface.

[0008] S2. The printed electrode with a metal layer on its surface prepared in step S1 is used as the working electrode, and together with the reference electrode and the counter electrode, it is immersed in a phosphoric acid compound solution to form a connected three-electrode system; and a voltage is applied, and after working at a specific temperature for a certain period of time, a printed electrode with a layered phosphoric acid compound on its surface is obtained.

[0009] S3. The printed electrode with layered phosphate compounds on its surface obtained in step S2 is washed three times with deionized water and dried to obtain an enzyme-like hydrogen peroxide sensor based on layered phosphate compounds.

[0010] As a further improvement of the present invention, in step S2, the specific temperature is 5 to 40°C; the voltage is 0.1V to 3.0V, preferably 0.8 to 2.0V; and the working time of the three-electrode system is 1 min to 100 min, preferably 2 min to 20 min.

[0011] As a further improvement of the present invention, in step S2, the phosphate ion concentration of the phosphoric acid compound solution is 0.001 mM to 2 M.

[0012] As a further improvement of the present invention, in step S2, the phosphoric acid compound solution includes one or more of NH4H2PO4, NaH2PO4, Na2HPO4, KH2PO4, (NH4)2HPO4, and K2HPO4.

[0013] As a further improvement of the present invention, in step S1, the metal layer is a metal element or a metal oxide, preferably a metal element.

[0014] As a further improvement of the present invention, the metallic element includes one or more of copper, zinc, calcium, magnesium, iron, nickel, and cobalt.

[0015] As a further improvement of the present invention, in step S2, the reference electrode is an Ag / AgCl electrode or a calomel electrode, and the counter electrode is a platinum electrode or a carbon electrode.

[0016] As a further improvement of the present invention, in step S1, the method of introducing a metal layer on the surface of the conductive material includes one of chemical plating, magnetron sputtering, and atomic layer deposition.

[0017] The present invention also provides an enzyme-like hydrogen peroxide sensor based on layered phosphate compounds prepared by any of the above-described preparation methods, the enzyme-like hydrogen peroxide sensor comprising a conductive material, a metal layer on the surface of the conductive material, and a two-dimensional layered phosphate compound loaded on the surface of the metal layer.

[0018] As a further improvement of the present invention, when the enzyme-like hydrogen peroxide sensor is used, it can be connected to an adapter and an external electrochemical workstation to detect hydrogen peroxide.

[0019] The beneficial effects of this invention are:

[0020] 1. This invention discloses an enzyme-like hydrogen peroxide sensor based on layered phosphate compounds and its preparation method. The method involves first preparing a printed electrode with a metal layer on its surface, then immersing it, along with a reference electrode and a counter electrode, in a phosphate compound solution to form a connected three-electrode system. A voltage is applied, and the electrode operates at a specific temperature for a certain time to obtain a printed electrode with layered phosphate compounds on its surface. Finally, the electrode is washed three times with deionized water and dried to obtain the enzyme-like hydrogen peroxide sensor based on layered phosphate compounds. This invention introduces a metal layer onto the surface of the printed electrode and then electropolymerizes it to coat the surface with layered phosphate compounds, thus obtaining an enzyme-like hydrogen peroxide detection sensor. Compared with traditional enzyme-like sensor preparation methods, this method eliminates the need for organic polymers, directly producing a sensor with a two-dimensional layered phosphate compound structure on its surface. The method is simple, has a short preparation cycle, and is less expensive than existing enzyme-free sensors. Furthermore, this enzyme-like hydrogen peroxide sensor has multiple reactive sites, resulting in high sensitivity for hydrogen peroxide detection and significant market application potential.

[0021] 2. This invention uses phosphate compounds instead of enzymes to prepare a hydrogen peroxide sensor with similar detection performance under enzyme-free conditions, avoiding the instability of sensor properties caused by difficulties in enzyme immobilization and easy inactivation in existing technologies. Furthermore, the generated layered structure of metal-phosphate compounds increases the specific surface area and the number of reactive sites, which is beneficial to improving the sensor's sensitivity. The enzyme-like hydrogen peroxide sensor based on layered phosphate compounds exhibits high catalytic activity, good sensitivity, and strong anti-interference ability in the detection of hydrogen peroxide, achieving rapid detection of hydrogen peroxide, and the sensor is reusable.

[0022] 3. This invention enables the in-situ growth of phosphoric acid compounds on the surface of printed electrodes through an electrochemical method, which greatly shortens the preparation time of the sensor. Compared with existing enzyme-like sensors, the preparation time is reduced by tens of times. Moreover, this method does not require prior organic compounding, and the preparation method is fast and simple, which is conducive to industrial production. Attached Figure Description

[0023] Figure 1 This is a SEM image of the bare printed electrode used in Embodiment 1 of the present invention.

[0024] Figure 2 This is a SEM image of a printed electrode with a layered phosphate compound attached to its surface, as described in Embodiment 1 of the present invention.

[0025] Figure 3 This is a curve showing the fitting of the current response values ​​of the enzyme-like hydrogen peroxide sensor of Embodiment 1 of the present invention to different concentrations of hydrogen peroxide.

[0026] Figure 4 The figure shows the anti-interference test results of the enzyme-like hydrogen peroxide sensor of Example 1 of the present invention. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] It should also be noted that, in order to avoid obscuring the present invention with unnecessary details, only the structures and / or processing steps closely related to the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.

[0029] Additionally, it should be noted that the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0030] A method for preparing an enzyme-like hydrogen peroxide sensor based on layered phosphate compounds includes the following steps:

[0031] S1. Introduce a metal layer on the surface of a conductive material to obtain a printed electrode with a metal layer on the surface.

[0032] S2. The printed electrode with a metal layer on its surface prepared in step S1 is used as the working electrode, and together with the reference electrode and the counter electrode, it is immersed in a phosphoric acid compound solution to form a connected three-electrode system; and a voltage is applied, and after working at a specific temperature for a certain period of time, a printed electrode with a layered phosphoric acid compound on its surface is obtained.

[0033] S3. The printed electrode with layered phosphate compounds on its surface obtained in step S2 is washed three times with deionized water and dried to obtain an enzyme-like hydrogen peroxide sensor based on layered phosphate compounds.

[0034] This invention uses phosphate compounds to replace enzymes, and prepares a hydrogen peroxide sensor with similar detection performance under enzyme-free conditions. This avoids the problems of unstable sensor properties caused by the difficulty of enzyme immobilization and easy inactivation in the prior art. Moreover, the generated metal-phosphate compound layered structure increases the specific surface area and increases the number of reactive sites, which is beneficial to improving the sensitivity of the sensor.

[0035] Specifically, in step S2, the specific temperature is 5–40°C; the voltage is 0.1V–3.0V, preferably 0.8–2.0V; the working time of the three-electrode system is 1 min–100 min, preferably 2 min–20 min; and the phosphate ion concentration of the phosphoric acid compound solution is 0.001 mM–2 M. This invention controls the electropolymerization growth of the phosphoric acid compound in solution with a metal layer as the substrate by limiting the temperature and voltage of the electrochemical process, causing it to grow into a regularly structured, uniformly dispersed two-dimensional layered structure. Simultaneously, by limiting the working time of the three-electrode system and the concentration of phosphate ions, the enrichment degree of the phosphoric acid compound on the surface of the printed electrode is controlled, avoiding segregation.

[0036] Specifically, in step S2, the phosphoric acid compound solution includes one or more of NH4H2PO4, NaH2PO4, Na2HPO4, KH2PO4, (NH4)2HPO4, and K2HPO4. The reference electrode is an Ag / AgCl electrode or a calomel electrode, and the counter electrode is a platinum electrode or a carbon electrode.

[0037] In some specific embodiments, the phosphoric acid compound solution is used together with sodium chloride solution or potassium chloride solution as an electrolyte solution to achieve in-situ growth of the phosphoric acid compound on the surface of the printed electrode.

[0038] In step S1, the metal layer is a metallic element or a metal oxide, preferably a metallic element; the metallic element includes one or more of copper, zinc, calcium, magnesium, iron, nickel, and cobalt. Methods for introducing a metal layer onto the surface of a conductive material include chemical plating, magnetron sputtering, and atomic layer deposition; for example, the specific steps for introducing a metal layer onto the surface of a conductive material using chemical plating are as follows:

[0039] SS1. Take an appropriate amount of electroplating solution and drop it into the groove on the surface of the printed electrode, allowing the electrolyte solution to completely wet the printed electrode. This electrode serves as the working electrode, connected to the reference electrode and counter electrode in the electrolyte solution, forming a three-electrode system. The electroplating solution contains Cu. S A mixed solution of O4·5H2O, acetic acid, and deionized water;

[0040] SS2. Insert the printed electrode into the adapter and connect it to an external electrochemical workstation; connect the modified electrode to the working electrode, the Ag / AgCl electrode or calomel electrode to the reference electrode, and the outer carbon electrode or platinum sheet electrode as the counter electrode. Apply voltage and allow it to operate for a period of time; wait for a uniform purplish-red metallic coating to appear on the surface of the working electrode of the printed electrode, then turn off the power to obtain a printed electrode with a copper metallic layer on its surface.

[0041] It should be noted that, taking a copper metal layer as an example to explain the layered structure formation process, a layer of copper metal is first electroplated on the surface of the printed electrode, which is then used as the working electrode. This electrode, along with the reference electrode and the counter electrode, is placed in a phosphate compound solution. A suitable voltage is applied to bring it to the redox potential of copper, causing Cu to oxidize to Cu. 2+ Copper ions coordinate with phosphoric acid compounds to form copper hydroxyphosphate Cu2(OH)PO4, which can grow into layered crystals of a certain shape as the reaction proceeds.

[0042] This invention utilizes an electrochemical method to grow phosphate compounds in situ on the surface of a printed electrode, significantly reducing sensor fabrication time by tens of times compared to existing enzyme-like sensors. Compared to traditional enzyme-like sensor fabrication methods, this method eliminates the need for organic polymers, directly producing sensors with a two-dimensional layered structure of phosphate compounds on their surface. The fabrication method is rapid and simple, and significantly cheaper than existing enzyme-free sensors, facilitating industrial production. Furthermore, this enzyme-like hydrogen peroxide sensor possesses numerous reactive sites, resulting in high sensitivity for hydrogen peroxide detection and demonstrating immense market potential.

[0043] An enzyme-like hydrogen peroxide sensor based on layered phosphate compounds prepared by the above method is disclosed. The enzyme-like hydrogen peroxide sensor includes a conductive material, a metal layer on the surface of the conductive material, and a two-dimensional layered phosphate compound loaded on the surface of the metal layer.

[0044] When using an enzyme-like hydrogen peroxide sensor based on layered phosphate compounds, it can be connected to an adapter and an external electrochemical workstation for hydrogen peroxide detection. Furthermore, this enzyme-like hydrogen peroxide sensor exhibits high catalytic activity, good sensitivity, and strong anti-interference capabilities during hydrogen peroxide detection, enabling rapid detection. The sensor is also reusable.

[0045] In the application of enzyme-like hydrogen peroxide sensors based on layered phosphate compounds, this paper takes an enzyme-like hydrogen peroxide sensor prepared with copper as the metal layer as an example to explain the detection principle. The Cu in copper hydroxyphosphate... 2+ -OH combines with H2O2 to form a five-membered ring, producing a hydroxyl radical intermediate. Finally, hydrogen peroxide is catalytically reduced to water and oxygen. This process involves electron transfer, which generates an electric current. The higher the concentration of hydrogen peroxide, the greater the current generated.

[0046] Example 1

[0047] This embodiment provides an enzyme-like hydrogen peroxide sensor based on layered phosphoric acid compounds and its preparation method. The preparation method includes the following steps:

[0048] S1. Introduce a metal layer on the surface of a conductive material to obtain a printed electrode with a metal layer on the surface.

[0049] S11. Take 60 μL of electroplating solution and drop it onto the groove on the surface of the printed electrode, allowing the electrolyte solution to completely wet the printed electrode. This electrode serves as the working electrode, connected to the reference electrode and counter electrode in the electrolyte solution, forming a three-electrode system. The electroplating solution contains 0.5 g of Cu. S A mixed solution of O4·5H2O, 4 mL of acetic acid, and 45 mL of deionized water;

[0050] SS2. Insert the printed electrode into the adapter and connect it to an external electrochemical workstation; connect the modified electrode to the working electrode, the Ag / AgCl electrode or calomel electrode to the reference electrode, and the outer carbon electrode or platinum sheet electrode as the counter electrode. Apply a voltage of 0.3V and allow it to work for 4 minutes. When a uniform purplish-red metallic coating appears on the surface of the working electrode of the printed electrode, turn off the power to obtain a printed electrode with a copper metallic layer on the surface.

[0051] S2. The printed electrode with a copper metal layer on its surface, prepared in step S1, is used as the working electrode. It is immersed together with the reference electrode and the counter electrode in a phosphoric acid compound solution to form a connected three-electrode system. A voltage of 1.8V is applied, and the electrode is operated at 25°C for 10 minutes to obtain a printed electrode with a layered phosphoric acid compound on its surface. The phosphoric acid compound solution is a mixed solution including 2 g / L NH4H2PO4, 4.0 g / L NaCl, 0.6 g / L KCl, 1 g / L Na2HPO4, 1 g / L (NH4)2HPO4, and 0.2 g / L KH2PO4.

[0052] S3. The printed electrode with layered phosphate compounds on its surface obtained in step S2 is washed three times with deionized water and dried to obtain an enzyme-like hydrogen peroxide sensor based on layered phosphate compounds.

[0053] Please see Figures 1-2 As shown, Figure 1 This is a SEM image of the bare printed electrode used in Example 1. Figure 2 SEM image of the printed electrode with a layered phosphate compound coated on its surface, as shown in Example 1. Figure 1 and Figure 2 As can be seen from the comparison, after the method of this embodiment, a phosphoric acid compound is generated on the surface of the printed electrode. The phosphoric acid compound is layered, has a relatively regular structure, and is evenly distributed. The layered structure of the metal-phosphate compound on the surface of the printed electrode increases the specific surface area and increases the number of reactive sites, which is beneficial to improving the sensitivity of the enzyme-like hydrogen peroxide sensor.

[0054] Please see Figure 3 The figure shows the fitting curves obtained by testing the current response values ​​of the enzyme-like hydrogen peroxide sensor based on layered phosphate compounds prepared in Example 1 at different concentrations of hydrogen peroxide. As can be seen from the figure, the oxidation peak current (I) and the hydrogen peroxide concentration (C) exhibit a good linear relationship over a wide concentration range of 0.01 mM to 50 mM, with a linear correlation coefficient R0. 2 =0.998, indicating that the enzyme-like hydrogen peroxide sensor prepared in this embodiment has a good detection effect on hydrogen peroxide.

[0055] Please see Figure 4 The figure shows the anti-interference test results of the enzyme-like hydrogen peroxide sensor prepared in Example 1 based on layered phosphate compounds. As can be seen from the figure, inorganic compounds and organic substances, such as KCl, NaCl, uric acid, and glucose, do not significantly interfere with the enzyme-like hydrogen peroxide sensor.

[0056] Examples 2-7

[0057] Examples 2-7 provide enzyme-like hydrogen peroxide sensors based on layered phosphate compounds and their preparation methods. The difference between these and Example 1 is that the parameters in step S2 are different, as shown in the table below; the rest are roughly the same as in Example 1 and will not be repeated here.

[0058] Comparative Examples 1-3

[0059] Comparative Examples 1-3 provide enzyme-like hydrogen peroxide sensors based on layered phosphate compounds and their preparation methods. The difference between them and Example 1 is that the parameters in step S2 are different, as shown in the table below; the rest are roughly the same as in Example 1, and will not be repeated here.

[0060] Table 1. Parameter settings for Examples 2-7 and Comparative Examples 1-3

[0061] Example 2 0.1 25 10 Example 3 3.0 25 10 Example 4 1.8 5 10 Example 5 1.8 40 10 Example 6 1.8 25 1 Example 7 1.8 25 100 Comparative Example 1 4.0 25 10 Comparative Example 2 1.8 50 10 Comparative Example 3 1.8 25 150

[0062] The detection limit, detection range, and sensitivity of the enzyme-like hydrogen peroxide sensors prepared in Examples 1-7 and Comparative Examples 1-3 were tested, and the results are shown in the table below.

[0063] Table 2 Performance test results of Examples 1-7 and Comparative Examples 1-3

[0064] Example 1 1.7 0.01～50 177 Example 2 2.3 0.01～100 189 Example 3 3.4 0.001～50 174 Example 4 1.7 0.001～80 176 Example 5 2.4 0.01～80 168 Example 6 4.7 0.01～200 175 Example 7 3.4 0.001～200 186 Comparative Example 1 10 0.1～10 100 Comparative Example 2 8 0.01～1 80 Comparative Example 3 15 0.01～10 120

[0065] As shown in Table 2, the layered phosphate compound-based enzyme-like hydrogen peroxide electrochemical sensor prepared by this method of the present invention has a low detection limit, a wider detection range, and high sensitivity, and is expected to be used in the field of hydrogen peroxide electrochemical sensing. The detection data from Examples 1-7 and Comparative Examples 1-3 show that the voltage, temperature, and operating time during the electrochemical process of preparing the layered phosphate compound-based enzyme-like hydrogen peroxide sensor all affect the final two-dimensional layered structure, thereby affecting the detection performance of the enzyme-like hydrogen peroxide sensor for hydrogen peroxide.

[0066] Example 4

[0067] This embodiment provides an enzyme-like hydrogen peroxide sensor and its preparation method. Compared with Embodiment 1, the difference is that no metal layer is introduced into the printed electrode in step S1, and the process proceeds directly to step S2. The rest is roughly the same as Embodiment 1, and will not be described again here.

[0068] The printed electrode obtained in Example 4 was observed under an electron microscope, and almost no phosphate compounds were found on its surface. Hydrogen peroxide detection also revealed that the sensor did not have the ability to detect hydrogen peroxide. This indicates that without a metal layer, phosphate compounds are difficult to grow on the surface of the printed electrode, making it impossible to fabricate an enzyme-like hydrogen peroxide sensor based on layered phosphate compounds.

[0069] In summary, this invention provides an enzyme-like hydrogen peroxide sensor based on layered phosphate compounds and its preparation method. The method involves first introducing a metal layer onto the surface of a printed electrode, then electropolymerizing it to coat the surface with layered phosphate compounds, thus obtaining an enzyme-like hydrogen peroxide detection sensor. This invention uses phosphate compounds instead of enzymes, preparing a hydrogen peroxide sensor with similar detection performance under enzyme-free conditions, avoiding the instability problems caused by difficult enzyme immobilization and easy inactivation in existing technologies. Furthermore, the generated metal-phosphate compound layered structure increases the specific surface area, resulting in more reactive sites and improving sensor sensitivity. This sensor exhibits high catalytic activity, good sensitivity, and strong anti-interference properties during hydrogen peroxide detection, achieving rapid detection of hydrogen peroxide, and the sensor is reusable. This invention uses an electrochemical method to grow phosphate compounds in situ on the surface of the printed electrode, significantly shortening the sensor preparation time by tens of times compared to existing enzyme-like sensors. Compared with existing enzyme-like sensor preparation methods, this method does not require the participation of organic polymers and directly produces sensors with two-dimensional layered phosphoric acid compounds loaded on the surface. The preparation method is rapid and simple, and the cost is lower than that of existing enzyme-free sensors, which is conducive to industrial production and has great market application prospects.

[0070] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for preparing an enzyme-like hydrogen peroxide sensor based on layered phosphate compounds, characterized in that, Includes the following steps: S1. Introduce a metal layer on the surface of a conductive material to obtain a printed electrode with a metal layer on the surface. S2. The printed electrode with a metal layer on its surface prepared in step S1 is used as the working electrode, and together with the reference electrode and the counter electrode, it is immersed in a phosphoric acid compound solution to form a connected three-electrode system; and a voltage is applied, and after working at a specific temperature for a certain period of time, a printed electrode with a layered phosphoric acid compound on its surface is obtained. S3. The printed electrode with layered phosphate compound on its surface obtained in step S2 is washed three times with deionized water and dried to obtain an enzyme-like hydrogen peroxide sensor based on layered phosphate compound. In step S2, the specific temperature is 5–40°C, the voltage is 0.8–2.0V, and the working time of the three-electrode system is 2–20 minutes. In step S2, the phosphate ion concentration of the phosphoric acid compound solution is 0.001 mM to 2 M; the phosphoric acid compound solution includes one or more of NH4H2PO4, NaH2PO4, Na2HPO4, KH2PO4, (NH4)2HPO4, and K2HPO4.

2. The method for preparing an enzyme-like hydrogen peroxide sensor based on layered phosphoric acid compounds according to claim 1, characterized by, In step S1, the metal layer is an elemental metal or a metal oxide.

3. The method for preparing an enzyme-like hydrogen peroxide sensor based on layered phosphoric acid compounds according to claim 2, characterized by, The metallic element includes one or more of copper, zinc, calcium, magnesium, iron, nickel, and cobalt.

4. The method for preparing an enzyme-like hydrogen peroxide sensor based on layered phosphate compounds according to claim 1, characterized in that, In step S2, the reference electrode is an Ag / AgCl electrode or a calomel electrode, and the counter electrode is a platinum electrode or a carbon electrode.

5. The method for preparing an enzyme-like hydrogen peroxide sensor based on layered phosphate compounds according to claim 1, characterized in that, In step S1, the method for introducing a metal layer on the surface of the conductive material includes one of chemical plating, magnetron sputtering, and atomic layer deposition.

6. An enzyme-like hydrogen peroxide sensor based on layered phosphate compounds prepared by the preparation method according to any one of claims 1 to 5, characterized in that, The enzyme-like hydrogen peroxide sensor includes a conductive material, a metal layer on the surface of the conductive material, and a two-dimensional layered phosphoric acid compound loaded on the surface of the metal layer.

7. The layered phosphoric acid compound-based enzyme-like hydrogen peroxide sensor according to claim 6, characterized by When in use, the enzyme-like hydrogen peroxide sensor is connected to an adapter and then to an external electrochemical workstation to detect hydrogen peroxide.

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