Preparation method and application of boron-nitrogen co-doped porous carbon nanomaterial
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHENGDU RUIJUE SENSING TECHNOLOGY CO LTD
- Filing Date
- 2026-04-07
- Publication Date
- 2026-06-12
Smart Images
Figure CN122187015A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of detection technology, and in particular to a method for preparing boron-nitrogen co-doped porous carbon nanomaterials and their applications. Background Technology
[0002] Uric acid is the final product of purine metabolism in the human body, and its abnormal concentration is closely related to gout, kidney disease, and cardiovascular diseases. Currently, the main methods for detecting uric acid include high-performance liquid chromatography (HPLC) and colorimetry, but these methods generally suffer from drawbacks such as expensive instruments, cumbersome operation, and long processing times. Electrochemical sensors have attracted much attention due to their fast response, high sensitivity, and low cost. Existing electrochemical uric acid sensors are mainly divided into two categories: enzyme-based sensors, while having good specificity, suffer from enzyme activity that is easily affected by the environment, poor stability, and high cost; the key to non-enzyme sensors lies in the development of electrode modification materials. Metal-organic framework (MOF)-derived carbon materials are widely used in electrochemical sensing due to their large specific surface area and excellent conductivity. However, existing MOF-derived carbon materials mostly retain metal components, resulting in insufficient catalytic stability and potential biosafety risks. A few boron-nitrogen co-doped metal-free carbon materials are mostly used for other detection targets, and research on their application in uric acid electrochemical sensing is still limited. Furthermore, there is still room for improvement in the sensitivity and detection limit of existing technologies. Therefore, developing a MOF-derived boron-nitrogen co-doped porous carbon material with no metal residue, high catalytic activity, and good stability, and using it to construct a high-performance uric acid electrochemical sensor, has important application value. Summary of the Invention
[0003] The purpose of this invention is to address the problems of poor stability and biosafety risks of metal-based materials in existing non-enzymatic uric acid sensors, as well as the insufficient sensitivity and high detection limit of metal-free carbon materials in uric acid detection, and to provide a method for preparing boron-nitrogen co-doped porous carbon nanomaterials and their applications.
[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:
[0005] A method for preparing boron-nitrogen co-doped porous carbon nanomaterials includes mixing a boron doping source, a nitrogen doping source, and a metal-organic framework precursor, synthesizing a boron-nitrogen co-doped MOF precursor using a solvothermal method, subjecting the boron-nitrogen co-doped MOF precursor to high-temperature pyrolysis carbonization and acid washing treatments in sequence, and drying to obtain boron-nitrogen co-doped porous carbon nanomaterials.
[0006] This invention provides a method for preparing boron-nitrogen co-doped porous carbon nanomaterials. In the synthesis stage of the boron-nitrogen co-doped MOF precursor, boron and nitrogen heteroatoms are directly introduced. After carbonization, a porous carbon material with uniform heteroatomation is obtained. After acid washing, the metal components are completely removed, avoiding the poor catalytic stability and biosafety risks caused by metal residues, and obtaining the pure phase metal-free boron-nitrogen co-doped porous carbon nanomaterial.
[0007] This invention fully utilizes the topological advantages of MOF-derived carbon to prepare boron-nitrogen co-doped porous carbon nanomaterials with high specific surface area, hierarchical pore structure and abundant defect sites. The electronic structure and surface chemical environment of the boron-nitrogen co-doped porous carbon nanomaterials significantly improve the material's electrocatalytic oxidation activity and electronic conductivity for uric acid.
[0008] As a preferred embodiment of the present invention, the boron-containing doping source is selected from at least one of boric acid, sodium borohydride, trimethyl borate, triethyl borate, boron carbide, and boron nitride; the nitrogen-containing doping source is selected from at least one of urea, melamine, ammonia, ethylenediamine, pyrrole, and aniline.
[0009] As a preferred embodiment of the present invention, the metal ion in the metal-organic framework precursor is selected from at least one of Zn²⁺, Mg²⁺, Ca²⁺ and Al³⁺; the organic ligand in the metal-organic framework precursor is selected from at least one of terephthalic acid, trimesic acid, 2-methylimidazole and benzimidazole.
[0010] The metal ion in the metal-organic framework precursor is selected from at least one of Zn²⁺, Mg²⁺, Ca²⁺, and Al³⁺, preferably Zn²⁺; the organic ligand is selected from at least one of terephthalic acid, trimesoic acid, 2-methylimidazole, and benzimidazole, preferably 2-methylimidazole; the boron-containing dopant source is selected from at least one of boric acid, sodium borohydride, trimethyl borate, triethyl borate, boron carbide, and boron nitride, preferably boric acid; the nitrogen-containing dopant source is selected from at least one of urea, melamine, ammonia, ethylenediamine, pyrrole, and aniline, preferably melamine or urea.
[0011] The molar ratio of the metal-organic framework precursor to the organic ligand is 1:1-1:10, preferably 1:2-1:6; the amount of the boron-containing dopant source added is 1%-20% of the mass of the metal-organic framework precursor, preferably 5%-15%; the amount of the nitrogen-containing dopant source added is 1%-30% of the mass of the metal-organic framework precursor, preferably 10%-25%; the organic solvent is selected from at least one of N,N-dimethylformamide, methanol, ethanol, and deionized water; the solvothermal reaction temperature is 80-200℃, preferably 100-180℃; the reaction time is 6-48 hours, preferably 12-24 hours.
[0012] As a preferred embodiment of the present invention, the high-temperature pyrolysis carbonization treatment is carried out at a temperature of 600-1100℃, a heating rate of 1-10℃ / min, and a holding time of 1-6 hours; the inert atmosphere is at least one of nitrogen, argon, or helium.
[0013] The inert atmosphere is at least one of nitrogen, argon, or helium, preferably nitrogen; the high-temperature pyrolysis carbonization temperature is 600-1100℃, preferably 800-1000℃; the heating rate is 1-10℃ / min, preferably 2-5℃ / min; and the holding time is 1-6 hours, preferably 2-4 hours.
[0014] As a preferred embodiment of the present invention, the acid solution used in the pickling treatment is at least one of hydrochloric acid, sulfuric acid, and nitric acid, the pickling concentration is 0.1-3 mol / L, the pickling temperature is 25-80℃, and the pickling time is 2-24 hours.
[0015] The acid solution used in the pickling treatment is at least one of hydrochloric acid, sulfuric acid, and nitric acid, preferably hydrochloric acid; the acid concentration is 0.1-3 mol / L, preferably 0.5-2 mol / L; the acid temperature is 25-80℃, preferably 40-60℃; the acid time is 2-24 hours, preferably 6-12 hours; after acid washing, the material is centrifuged, washed with water until neutral, washed with alcohol, and dried to obtain the boron-nitrogen co-doped porous carbon nanomaterial.
[0016] An electrochemical uric acid sensor based on boron-nitrogen co-doped porous carbon nanomaterials includes a working electrode, a reference electrode, a counter electrode, a modification layer, and an insulating layer. The working electrode, the reference electrode, and the counter electrode form a three-electrode system for current conduction. The modification layer is electrically connected to the working electrode. The modification layer is prepared using a boron-nitrogen co-doped porous carbon nanomaterial prepared by the method described above. The modification layer is used to detect the concentration of uric acid molecules in a sample solution and generate a current signal. The insulating layer is disposed in the non-working area of the three-electrode system away from the modification layer. The insulating layer protects the three-electrode system and isolates the sample solution from the electrode system, keeping it away from the sensing element.
[0017] This invention provides an electrochemical uric acid sensor based on boron-nitrogen co-doped porous carbon nanomaterials, which exhibits excellent analytical performance for uric acid detection: high sensitivity, good selectivity, wide linear range, detection limit down to the nanomolar level, fast response speed, and strong stability. The sensor is simple to fabricate, low in cost, and has good repeatability, enabling rapid and accurate detection of uric acid in real biological samples such as serum and urine.
[0018] As a preferred embodiment of the present invention, the substrate electrode is at least one of a glassy carbon electrode, a gold electrode, a platinum electrode, or a screen-printed electrode.
[0019] A method for fabricating an electrochemical uric acid sensor based on boron-nitrogen co-doped porous carbon nanomaterials includes the following steps:
[0020] S1. Disperse boron-nitrogen co-doped porous carbon nanomaterials in a solvent, add a film-forming aid, and disperse evenly by ultrasonication to obtain a modified solution;
[0021] S2. Polish the base electrode to a mirror finish with alumina polishing powder, then ultrasonically clean it in anhydrous ethanol and deionized water for 2-5 minutes in sequence, and dry it with nitrogen for later use.
[0022] S3. The modification solution is coated on the surface of the substrate electrode and dried by infrared lamp or natural drying at room temperature to obtain the working electrode;
[0023] S4. The working electrode, reference electrode, and counter electrode are assembled into a three-electrode system to obtain an electrochemical uric acid sensor.
[0024] This invention provides a method for preparing an electrochemical uric acid sensor based on boron-nitrogen co-doped porous carbon nanomaterials. The method is simple to operate, has mild conditions, and a controllable structure. It also provides a complete industrialization implementation plan, is suitable for large-scale production, and has good industrialization prospects and application promotion value.
[0025] As a preferred embodiment of the present invention, the solvent in step S1 is at least one of water, ethanol, N,N-dimethylformamide, and N-methylpyrrolidone; the film-forming aid is at least one of Nafion, chitosan, and polyvinyl alcohol; and the concentration of boron-nitrogen co-doped porous carbon nanomaterials in the modification solution is 0.1-5 mg / mL.
[0026] As a preferred embodiment of the present invention, step S3 further includes an electrochemical activation step: performing cyclic voltammetric scanning on the working electrode in a phosphate buffer solution.
[0027] The working electrode was subjected to cyclic voltammetry scanning in phosphate buffer solution at a scan potential of -0.2 to 0.8 V, a scan rate of 50 mV / s, and 10 to 20 scan cycles to further improve the electrode response performance.
[0028] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:
[0029] 1. A method for preparing boron-nitrogen co-doped porous carbon nanomaterials, wherein boron and nitrogen heteroatoms are directly introduced during the synthesis stage of the boron-nitrogen co-doped MOF precursor, and a porous carbon material with uniform heteroatom doping is obtained after carbonization. The metal components are completely removed by acid washing, avoiding the poor catalytic stability and biosafety risks caused by metal residues, and a pure phase metal-free boron-nitrogen co-doped porous carbon nanomaterial is obtained. This invention fully utilizes the topological advantages of MOF-derived carbon, and the boron-nitrogen co-doped porous carbon nanomaterials prepared have high specific surface area, multi-level pore structure and abundant defect sites. The electronic structure and surface chemical environment of the boron-nitrogen co-doped porous carbon nanomaterials significantly improve the electrocatalytic oxidation activity and electronic conductivity of the material for uric acid.
[0030] 2. An electrochemical uric acid sensor based on boron-nitrogen co-doped porous carbon nanomaterials exhibits excellent analytical performance for uric acid detection: high sensitivity, good selectivity, wide linear range, detection limit down to the nanomolar level, fast response speed, and strong stability; the sensor has a simple fabrication process, low cost, and good repeatability, and can achieve rapid and accurate detection of uric acid in real biological samples such as serum and urine.
[0031] 3. A method for preparing an electrochemical uric acid sensor based on boron-nitrogen co-doped porous carbon nanomaterials. The method is simple to operate, has mild conditions, and a controllable structure. It also provides a complete industrialization implementation plan, is suitable for large-scale production, and has good industrialization prospects and application promotion value. Attached Figure Description
[0032] Figure 1 This is an electron microscope image of boron-nitrogen co-doped porous carbon nanomaterials, which is a method for preparing boron-nitrogen co-doped porous carbon nanomaterials.
[0033] Figure 2 This is an X-ray diffraction pattern of boron-nitrogen co-doped porous carbon nanomaterials, which is a method for preparing boron-nitrogen co-doped porous carbon nanomaterials.
[0034] Figure 3 This is an X-ray photoelectron spectrum of boron-nitrogen co-doped porous carbon nanomaterials prepared by a boron-nitrogen co-doped porous carbon nanomaterial preparation method;
[0035] Figure 4 This is a detection performance diagram of an electrochemical uric acid sensor based on boron-nitrogen co-doped porous carbon nanomaterials. Detailed Implementation
[0036] The present invention will now be described in detail with reference to the accompanying drawings.
[0037] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.
[0038] Example 1
[0039] The present invention discloses a method for preparing boron-nitrogen co-doped porous carbon nanomaterials, which includes mixing a boron doping source, a nitrogen doping source and a metal-organic framework precursor, synthesizing a boron-nitrogen co-doped MOF precursor by a solvothermal method, subjecting the boron-nitrogen co-doped MOF precursor to high-temperature pyrolysis carbonization treatment and acid washing treatment in sequence, and obtaining boron-nitrogen co-doped porous carbon nanomaterials after drying.
[0040] Furthermore, the boron-containing dopant source is selected from at least one of boric acid, sodium borohydride, trimethyl borate, triethyl borate, boron carbide, and boron nitride; the nitrogen-containing dopant source is selected from at least one of urea, melamine, ammonia, ethylenediamine, pyrrole, and aniline.
[0041] Furthermore, the metal ion in the metal-organic framework precursor is selected from at least one of Zn²⁺, Mg²⁺, Ca²⁺, and Al³⁺; the organic ligand in the metal-organic framework precursor is selected from at least one of terephthalic acid, trimesic acid, 2-methylimidazole, and benzimidazole.
[0042] Furthermore, the high-temperature pyrolysis carbonization treatment is carried out at a temperature of 600-1100℃, a heating rate of 1-10℃ / min, and a holding time of 1-6 hours; the inert atmosphere is at least one of nitrogen, argon, or helium.
[0043] Furthermore, the acid solution used in the pickling treatment is at least one of hydrochloric acid, sulfuric acid, and nitric acid, the pickling concentration is 0.1-3 mol / L, the pickling temperature is 25-80℃, and the pickling time is 2-24 hours.
[0044] In the synthesis stage of the boron-nitrogen co-doped MOF precursor, boron and nitrogen heteroatoms are directly introduced. After carbonization, a porous carbon material with uniform heteroatom doping is obtained. After acid washing, the metal components are completely removed, avoiding the poor catalytic stability and biosafety risks caused by metal residues, resulting in a pure-phase metal-free boron-nitrogen co-doped porous carbon nanomaterial. This invention fully utilizes the topological advantages of MOF-derived carbon. The boron-nitrogen co-doped porous carbon nanomaterial prepared has a high specific surface area, a multi-level pore structure, and abundant defect sites. The electronic structure and surface chemical environment of the boron-nitrogen co-doped porous carbon nanomaterial significantly improve the electrocatalytic oxidation activity and electronic conductivity of the material for uric acid.
[0045] In this embodiment, the specific preparation steps of the boron-nitrogen co-doped porous carbon nanomaterial are as follows:
[0046] (1) Weigh 1.487 g of zinc nitrate hexahydrate and dissolve it in 40 mL of methanol to obtain solution A; weigh 1.648 g of 2-methylimidazole, 0.223 g of boric acid, and 0.297 g of melamine and dissolve them in 40 mL of methanol to obtain solution B. Quickly pour solution A into solution B, stir at room temperature for 2 hours, transfer to a 100 mL reaction vessel, and solvothermal react at 120 °C for 12 hours. The reaction product is centrifuged, washed three times with methanol, and vacuum dried at 60 °C for 12 hours to obtain the boron-nitrogen co-doped MOF precursor.
[0047] (2) The boron-nitrogen co-doped MOF precursor was placed in a tube furnace and heated to 900°C at 5°C / min under a nitrogen atmosphere. The temperature was held for 2 hours and then naturally cooled to room temperature to obtain the carbonized product.
[0048] (3) Disperse the carbonization product in 1 mol / L hydrochloric acid solution, stir at 60°C for 12 hours, centrifuge, wash with deionized water until the filtrate is neutral, wash once with ethanol, and vacuum dry at 60°C for 12 hours to obtain the boron-nitrogen co-doped porous carbon nanomaterial, denoted as BNC-900.
[0049] In practical applications, the preparation method in step (2) is replaced by placing the boron-nitrogen co-doped MOF precursor in a tube furnace for pre-carbonization for 2 hours; then, the temperature is increased to 900℃ at 5℃ / min and held for 2 hours. The resulting boron-nitrogen co-doped porous carbon nanomaterial exhibits higher structural stability.
[0050] like Figure 1 As shown, the boron-nitrogen co-doped porous carbon nanomaterial BNC-900 exhibits a typical nanosheet structure with uniform distribution and a thickness of approximately 10-20 nm. Its rough, porous surface is beneficial for exposing active sites and facilitating electron transport. Figure 2 As shown, the boron-nitrogen co-doped porous carbon nanomaterial BNC-900 exhibits only two broadened diffraction peaks near 24° and 44°, corresponding to the (002) and (101) crystal planes of carbon, respectively. There are no characteristic diffraction peaks of metals or metal compounds, indicating that the acid washing treatment has completely removed the metal components, and the material has an amorphous carbon structure. Figure 3 As shown, the boron-nitrogen co-doped porous carbon nanomaterial BNC-900 exhibits characteristic peaks for four elements: C, N, B, and O, but lacks a Zn element signal. This indicates that boron and nitrogen heteroatoms have been successfully doped into the carbon framework.
[0051] In practical applications, the boron-nitrogen co-doped porous carbon nanomaterial can also be prepared as follows: 0.734 g of zinc nitrate hexahydrate is dissolved in 30 mL of N,N-dimethylformamide, denoted as solution A; 0.415 g of terephthalic acid, 0.110 g of trimethyl borate, and 0.150 g of urea are dissolved in 30 mL of N,N-dimethylformamide, denoted as solution B. Solution A and solution B are mixed, ultrasonically dispersed for 10 minutes, transferred to a 100 mL reactor, and solvothermically reacted at 130 °C for 24 hours. The reaction product is centrifuged, washed three times with N,N-dimethylformamide, and vacuum dried at 60 °C for 12 hours to obtain the boron-nitrogen co-doped MOF precursor. The boron-nitrogen co-doped MOF precursor is placed in a tube furnace, heated to 1000 °C at 3 °C / min under an argon atmosphere, held at that temperature for 1 hour, and naturally cooled to room temperature to obtain the carbonized product. The carbonization product was dispersed in a 0.5 mol / L sulfuric acid solution, stirred at 50°C for 8 hours, centrifuged, washed with deionized water until neutral, and vacuum dried at 60°C for 12 hours to obtain the boron-nitrogen co-doped porous carbon nanomaterial, denoted as BNC-1000.
[0052] Example 2
[0053] The present invention discloses an electrochemical uric acid sensor based on boron-nitrogen co-doped porous carbon nanomaterials, comprising a working electrode, a reference electrode, a counter electrode, a modification layer, and an insulating layer. The working electrode, the reference electrode, and the counter electrode form a three-electrode system for current conduction. The modification layer is electrically connected to the working electrode. The modification layer is prepared using a boron-nitrogen co-doped porous carbon nanomaterial prepared by the method described in Example 1. The modification layer is used to detect the concentration of uric acid molecules in the sample solution and generate a current signal. The insulating layer is disposed in the non-working area of the three-electrode system away from the modification layer, and is used to protect the three-electrode system and isolate the sample solution from the electrode system at the sensing element end.
[0054] Furthermore, the substrate electrode is at least one of a glassy carbon electrode, a gold electrode, a platinum electrode, or a screen-printed electrode.
[0055] It exhibits excellent analytical performance for uric acid detection: high sensitivity, good selectivity, wide linear range, detection limit down to the nanomolar level, fast response speed, and strong stability; the sensor is simple to manufacture, low in cost, and has good repeatability, enabling rapid and accurate detection of uric acid in real biological samples such as serum and urine.
[0056] In this embodiment, the substrate electrode is pretreated as follows: the substrate electrode is selected from at least one of glassy carbon electrode, gold electrode, platinum electrode or screen-printed electrode, preferably glassy carbon electrode; the substrate electrode is polished to a mirror finish with 0.3μm and 0.05μm alumina polishing powder in sequence, ultrasonically cleaned in anhydrous ethanol and deionized water for 2-5 minutes in sequence, and dried with nitrogen gas for later use.
[0057] This embodiment also provides a method for preparing an electrochemical uric acid sensor based on boron-nitrogen co-doped porous carbon nanomaterials, comprising the following steps:
[0058] S1. Disperse boron-nitrogen co-doped porous carbon nanomaterials in a solvent, add a film-forming aid, and disperse evenly by ultrasonication to obtain a modified solution;
[0059] S2. Polish the base electrode to a mirror finish with alumina polishing powder, then ultrasonically clean it in anhydrous ethanol and deionized water for 2-5 minutes in sequence, and dry it with nitrogen for later use.
[0060] S3. The modification solution is coated on the surface of the substrate electrode and dried by infrared lamp or natural drying at room temperature to obtain the working electrode;
[0061] S4. The working electrode, reference electrode, and counter electrode are assembled into a three-electrode system to obtain an electrochemical uric acid sensor.
[0062] Furthermore, the solvent in step S1 is at least one of water, ethanol, N,N-dimethylformamide, and N-methylpyrrolidone; the film-forming aid is at least one of Nafion, chitosan, and polyvinyl alcohol; and the concentration of boron-nitrogen co-doped porous carbon nanomaterials in the modification solution is 0.1-5 mg / mL.
[0063] Furthermore, step S3 also includes an electrochemical activation step: performing cyclic voltammetric scans on the working electrode in a phosphate buffer solution.
[0064] The preparation method provided in this embodiment is simple to operate, has mild conditions, and a controllable structure. It also provides a complete industrialization implementation plan, is suitable for large-scale production, and has good industrialization prospects and application promotion value.
[0065] In this embodiment, the modification solution was prepared as follows: 2 mg of BNC-900 material prepared in Example 1 was weighed and dispersed in 1 mL of ethanol / water mixed solvent (volume ratio 4:1). 10 μL of 0.5 wt% Nafion solution was added, and the mixture was ultrasonically dispersed for 30 minutes to obtain a uniform 2 mg / mL modification solution.
[0066] The substrate electrode pretreatment is as follows: the glassy carbon electrode (3 mm in diameter) is polished to a mirror finish with 0.3 μm and 0.05 μm alumina polishing powders, then ultrasonically cleaned in anhydrous ethanol and deionized water for 3 minutes each, and dried with nitrogen gas for later use.
[0067] Preparation of working electrode: Take 8 μL of the above modification solution with a microsyringe and drop it onto the surface of the pretreated glassy carbon electrode. Let it dry naturally at room temperature to obtain the BNC-900 modified working electrode.
[0068] Sensor assembly: Assemble the working electrode, the reference electrode, and the counter electrode into a three-electrode system, and connect it to an electrochemical workstation to obtain the electrochemical uric acid sensor.
[0069] like Figure 4 As shown, 0.1 mol / L phosphate buffer (pH 7.0) was prepared, and uric acid standard solution was added to achieve final concentrations of 50 μM, 100 μM, 200 μM, 500 μM, 800 μM, 1000 μM, and 1250 μM. The electrochemical uric acid sensor was used for detection using differential pulse voltammetry, and the peak current values of uric acid oxidation at each concentration were recorded. A standard curve was plotted with uric acid concentration on the x-axis and peak current values on the y-axis. The results showed a good linear relationship between uric acid concentration and peak current values in the range of 50-1250 μM, with a linear regression equation of I(μA) = 18.58C(μM) + 0.54 and a correlation coefficient R0. 2 =0.994.
[0070] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A method for preparing boron-nitrogen co-doped porous carbon nanomaterials, characterized in that, The method involves mixing a boron-doped source, a nitrogen-doped source, and a metal-organic framework precursor, and synthesizing a boron-nitrogen co-doped MOF precursor using a solvothermal method. The boron-nitrogen co-doped MOF precursor is then subjected to high-temperature pyrolysis carbonization and acid washing treatments, and finally dried to obtain boron-nitrogen co-doped porous carbon nanomaterials.
2. The method for preparing boron-nitrogen co-doped porous carbon nanomaterials according to claim 1, characterized in that, The boron-containing dopant source is selected from at least one of boric acid, sodium borohydride, trimethyl borate, triethyl borate, boron carbide, and boron nitride; the nitrogen-containing dopant source is selected from at least one of urea, melamine, ammonia, ethylenediamine, pyrrole, and aniline.
3. The method for preparing boron-nitrogen co-doped porous carbon nanomaterials according to claim 1, characterized in that, The metal ion in the metal-organic framework precursor is selected from at least one of Zn²⁺, Mg²⁺, Ca²⁺ and Al³⁺; the organic ligand in the metal-organic framework precursor is selected from at least one of terephthalic acid, trimesic acid, 2-methylimidazole and benzimidazole.
4. A method for preparing boron-nitrogen co-doped porous carbon nanomaterials according to any one of claims 1 to 3, characterized in that, The high-temperature pyrolysis carbonization treatment is carried out at a temperature of 600-1100℃, a heating rate of 1-10℃ / min, and a holding time of 1-6 hours; the inert atmosphere is at least one of nitrogen, argon, or helium.
5. A method for preparing boron-nitrogen co-doped porous carbon nanomaterials according to any one of claims 1 to 3, characterized in that, The acid solution used in the pickling treatment is at least one of hydrochloric acid, sulfuric acid, and nitric acid, with an acid concentration of 0.1-3 mol / L, an acid temperature of 25-80℃, and an acid time of 2-24 hours.
6. An electrochemical uric acid sensor based on boron-nitrogen co-doped porous carbon nanomaterials, characterized in that, The device comprises a working electrode, a reference electrode, a counter electrode, a modification layer, and an insulating layer. The working electrode, the reference electrode, and the counter electrode form a three-electrode system for current conduction. The modification layer is electrically connected to the working electrode. The modification layer is a boron-nitrogen co-doped porous carbon nanomaterial prepared using a method described in any one of claims 1 to 5. The modification layer is used to detect the concentration of uric acid molecules in a sample solution and generate a current signal. The insulating layer is disposed in a non-working area of the three-electrode system away from the modification layer. The insulating layer protects the three-electrode system and isolates the sample solution from the electrode system, keeping it away from the sensing element.
7. An electrochemical uric acid sensor based on boron-nitrogen co-doped porous carbon nanomaterials according to claim 6, characterized in that, The substrate electrode is at least one of glassy carbon electrode, gold electrode, platinum electrode, or screen-printed electrode.
8. A method for preparing an electrochemical uric acid sensor based on boron-nitrogen co-doped porous carbon nanomaterials, characterized in that, The steps for preparing an electrochemical uric acid sensor based on boron-nitrogen co-doped porous carbon nanomaterials as described in any one of claims 6 to 7 are as follows: S1. Disperse boron-nitrogen co-doped porous carbon nanomaterials in a solvent, add a film-forming aid, and disperse evenly by ultrasonication to obtain a modified solution; S2. Polish the base electrode to a mirror finish with alumina polishing powder, then ultrasonically clean it in anhydrous ethanol and deionized water for 2-5 minutes in sequence, and dry it with nitrogen for later use. S3. The modification liquid prepared in step S1 is coated onto the surface of the substrate electrode after pretreatment in step S2, and dried by infrared lamp or natural drying at room temperature to obtain the working electrode. S4. The working electrode, reference electrode, and counter electrode are assembled into a three-electrode system to obtain an electrochemical uric acid sensor.
9. The method for preparing an electrochemical uric acid sensor based on boron-nitrogen co-doped porous carbon nanomaterials according to claim 8, characterized in that, The solvent in step S1 is at least one of water, ethanol, N,N-dimethylformamide, and N-methylpyrrolidone; the film-forming aid is at least one of Nafion, chitosan, and polyvinyl alcohol; and the concentration of boron-nitrogen co-doped porous carbon nanomaterials in the modification solution is 0.1-5 mg / mL.
10. The method for preparing an electrochemical uric acid sensor based on boron-nitrogen co-doped porous carbon nanomaterials according to claim 9, characterized in that, Step S3 also includes an electrochemical activation step: performing cyclic voltammetric scans on the working electrode in a phosphate buffer solution.