Preparation and application of polyacid-derived dissimilar metal sulfide enzyme material
Through one-step hydrothermal synthesis method of cobalt-molybdenum-based polymetallic acid oxylate precursor and cadmium sulfide and thiourea, polyacid-derived isometallic sulfide enzyme materials were prepared, solving the problems of poor stability and low activity of traditional isometallic sulfide materials, and achieving efficient hydroquinone detection.
Patent Information
- Application Number
- CN202510273466.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-09
- Publication Date
- 2025-06-06
AI Technical Summary
Traditional isometal sulfide materials have poor stability and low activity of single metal sulfide enzymes, making it difficult to meet the needs of efficient detection of hydroquinone.
By one-step hydrothermal synthesis of cobalt-molybdenum-based polymetallic acid acid precursor and cadmium sulfide and thiourea, polyacid-derived isometallic sulfide enzyme materials were prepared, with the chemical composition of MoS2-Co9S8-CdS and the black powdery appearance.
The material exhibits high catalytic activity and good cycle stability, and can effectively catalyze the fading reaction of oxTMB and hydroquinone, with excellent colorimetric detection performance and low detection limit.
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Figure CN120094611A_ABST
Abstract
Description
Technical Field
[0001] The invention discloses a polyacid-derived heterometallic sulfide enzyme material. Background Art
[0002] Compared with natural enzymes, artificial nanozymes have the advantages of low cost, easy processing, high stability and catalytic efficiency, making them a good substitute for natural enzymes. Studies have found that materials such as precious metals, carbon materials, transition metal oxides, and transition metal sulfides have been confirmed to have peroxidase activity. As an important organic chemical raw material, hydroquinone has stable chemical properties and is widely used in many fields such as pharmaceuticals, dyes, cosmetics, and food. However, due to its low degradation rate and high toxicity, it is considered an environmental pollutant during the production process and has a certain impact on human health. Therefore, it is of great significance to establish a convenient and sensitive method for detecting HQ. Among the many existing methods for detecting phenolic compounds, colorimetric sensing is a very promising method. In H 2 O 2 With the assistance of a catalyst, hydroquinone can reduce the oxidized oxTMB (oxTMB) to 3,3',5,5'-tetramethylbenzidine (TMB), thereby fading the blue color of the solution.
[0003] Polyoxometalates (POMs) (also known as polyacids) are nano-oxide clusters with reversible oxidative activity. They have the characteristics of modifiable structure and adjustable physical and chemical properties. They can be used as basic materials for a variety of applications, and can also be used as pre-assembled platforms to provide different transition metal sources and fixed bimetallic ratios. The molecular clusters of polyoxometalates are very stable and show strong and stable interactions when combined with various crystalline materials. They have broad application prospects in the fields of colorimetric sensing and photocatalytic degradation. Moreover, polyoxometalates have been shown to have peroxidase-like activity and can be used to detect H 2 O 2 and other biologically significant micromolecules. Metal sulfides are considered promising peroxidase-like candidates because of their weak metal-sulfur (MS) bonds that promote kinetic conversion reactions. Transition metal sulfide composites with high activity and good stability can be prepared using POMs as precursors. Due to the good application prospects of polyacid-derived heterometallic sulfide materials, we studied and prepared a polyacid-derived heterometallic sulfide enzyme material that has not been reported in the literature. Summary of the invention
[0004] The purpose of the present invention is to solve the problems of poor stability of traditional heterometallic sulfide materials and low activity of single metal sulfide enzymes, and to provide a preparation method and application of a polyacid-derived heterometallic sulfide enzyme material.
[0005] In order to solve the above technical problems, the present invention is achieved through the following technical solutions:
[0006] 1. Preparation of cobalt-molybdenum-based polyoxometalate precursor: Add ammonium molybdate to distilled water and heat to boiling, then add a mixed solution of cobalt sulfate and hydrogen peroxide to the molybdate solution and stir to react for 1 hour, then filter the reaction solution, and cool the filtrate naturally to room temperature and let it stand, thereby obtaining a dark green powder with the molecular formula (NH) 6 Mo 7 O 24 ·4H 2 O;
[0007] 2. Preparation of cadmium sulfide: dissolving cadmium nitrate in ethylenediamine and stirring evenly, then adding thiourea to the above solution and stirring evenly, then transferring the reaction solution to a polytetrafluoroethylene reactor, and then reacting at a temperature of 160°C for 24 hours. After the reaction solution temperature drops to room temperature, washing is performed to obtain a yellow powder;
[0008] 3. Preparation of a polyacid-derived heterometallic sulfide enzyme material: Add the cobalt-molybdenum-based polyacid precursor and thiourea prepared in step 1 to distilled water and stir evenly, then add the dopant in step 2 to the above solution and stir evenly, then transfer the reaction solution to a polytetrafluoroethylene reactor, and then react at a temperature of 200°C for 24 hours. After the reaction solution temperature drops to room temperature, it is washed to obtain a black powder, i.e., a polyacid-derived heterometallic sulfide enzyme material. The chemical composition of the nanosphere is MoS 2 -Co 9 S 8 -CdS, black powder in appearance;
[0009] 4. A polyacid-derived heterometallic sulfide enzyme material has peroxidase-like activity and higher catalytic activity than other complexes. As a colorimetric detection catalyst, it can catalyze the fading reaction of oxTMB and hydroquinone and has excellent catalytic performance.
[0010] Compared with the prior art, the present invention has the following characteristics:
[0011] 1. The present invention successfully prepared a polyacid-derived heterometallic sulfide enzyme material by using cobalt-molybdenum-based polyoxometalate as a precursor, cadmium sulfide and thiourea through a one-step hydrothermal synthesis method; a certain content of 1T-MoS 2 The defective structure makes it have high catalytic activity, and the abundant active sites make the polyacid-derived heterometallic sulfide material of the present invention have higher peroxidase-like catalytic activity.
[0012] 2. In H 2 O 2The colorimetric detection performance was tested by UV spectroscopy in aqueous solutions of TMB and hydroquinone. In the range of 0-80 μM, the absorbance value of hydroquinone at 625 nm decreased linearly with the increase of concentration. According to the three-fold signal-to-noise ratio rule, the detection limit of hydroquinone was only 0.33 μM. Compared with other methods for detecting HQ, MoS 2 -Co 9 S 8 -CdS has a relatively low detection limit for hydroquinone. This shows that the polyacid-derived heterometallic sulfide enzyme material of the present invention has excellent colorimetric detection performance. The cyclic stability of the polyacid-derived heterometallic sulfide mimetic enzyme was evaluated by colorimetric detection of hydroquinone. After three cycle experiments, MoS 2 -Co 9 S 8 The catalytic activity of -CdS can be maintained above 90% without obvious structural changes, indicating that the polyacid-derived heterometallic sulfide enzyme material has good cyclic stability. 2 -Co 9 S 8 -CdS mimetic enzyme has excellent peroxidase-like activity and a stable curve platform in the catalytic reaction. Its catalytic performance is mainly due to its special structure, forming a nanoflower structure formed by the crisscrossing of unique nanosheets, and having abundant space, which is conducive to the contact surface between ions and reactants, providing more active sites for the reaction and improving the activity of the catalytic reaction. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 This is an example - a basic structural unit diagram of a polyacid-derived heterometallic sulfide enzyme material.
[0014] Figure 2 Example - Schematic diagram of the formation process of a polyacid-derived heterometallic sulfide enzyme material
[0015] Figure 3 This is an example - a powder X-ray diffraction pattern of a polyacid-derived heterometallic sulfide enzyme material.
[0016] Figure 4 This is an X-ray photoelectron image of an embodiment - a polyacid-derived heterometallic sulfide enzyme material.
[0017] Figure 5 This is a scanning electron micrograph of an embodiment - a polyacid-derived heterometallic sulfide enzyme material.
[0018] Figure 6 Example - A polyacid-derived heterometallic sulfide enzyme material in H 2 O 2 , UV spectra of TMB and hydroquinone solutions. DETAILED DESCRIPTION
[0019] The process parameters and process routes of the present invention are not limited to the specific implementation schemes listed below. The specific implementation schemes listed below only illustrate the present invention and are not limited to the process parameters and process routes described in the embodiments of the present invention. Researchers in this field should understand that the present invention can be modified or equivalently replaced in practical applications to achieve the same technical effects. As long as the application requirements are met, they are within the scope of protection of the present invention.
[0020] Specific implementation method 1: A preparation method of a polyacid-derived isometallic sulfide enzyme material in this implementation method is completed by the following steps:
[0021] 1. Preparation of cobalt-molybdenum-based polyoxometalate precursor: 30.9 g of ammonium molybdate was added to 20 mL of distilled water and heated to boiling, and then a mixed solution of 4.2 g of cobalt sulfate and 2.0 g of hydrogen peroxide was added to the molybdate solution and stirred for reaction for 1 h, and then the reaction solution was filtered and the filtrate was naturally cooled to room temperature and allowed to stand, thereby obtaining a dark green powder;
[0022] 2. Preparation of cadmium sulfide: 0.39 g of cadmium nitrate was dissolved in 10 mL of ethylenediamine and stirred evenly, then 0.39 g of thiourea was added to the above solution and stirred evenly, and then the reaction solution was transferred to a polytetrafluoroethylene reactor, and then reacted at a temperature of 160°C for 24 hours. After the reaction solution temperature was cooled to room temperature, it was washed to obtain a yellow powder;
[0023] 3. Preparation of a polyacid-derived heterometallic sulfide enzyme material: Add the cobalt-molybdenum-based polyacid precursor and thiourea prepared in step 1 into distilled water and stir evenly, then add the dopant in step 2 into the above solution and stir evenly, then transfer the reaction solution to a polytetrafluoroethylene reactor, and then react at a temperature of 200°C for 24 hours. After the reaction solution temperature is lowered to room temperature, it is washed to obtain a black powder, i.e., a polyacid-derived heterometallic sulfide enzyme material;
[0024] 4. Colorimetric detection performance of a polyacid-derived heterometallic sulfide enzyme material: TMB, hydroquinone, and H 2 O 2 and polyacid-derived heterometallic sulfides MoS 2 -Co 9 S 8 -CdS. The volume of the mixed solution was set to 2 mL, and the volume of the reaction solution was supplemented with an acetate buffer solution of pH = 4.0. After reacting at room temperature for 10 min, the absorbance of the reaction solution at 652 nm was recorded using a UV-visible spectrophotometer.
[0025] Specific implementation method 2: Specific implementation method 1: In the cobalt-molybdenum-based polyoxometalate precursor described in step 1, the molar ratio of ammonium molybdate, cobalt sulfate, and hydrogen peroxide is 1: (0.5-0.7): (2.25-2.45);
[0026] Specific embodiment 3: This embodiment differs from specific embodiment 1 in that the metal cobalt salt in step 1 is cobalt acetate, cobalt nitrate or cobalt chloride. The rest is the same as specific embodiments 1 to 2.
[0027] Specific implementation method 4: In the method for preparing a polyacid-derived heterometallic sulfide enzyme material as described in step 3 of specific implementation method 1, the volume ratio of the molar number of the polyoxometalate precursor to distilled water is 0.04mmol:15mL.
[0028] Specific embodiment 5: The difference between this embodiment and specific embodiment 1 is that the reaction temperature in step 3 is 160-220° C. and the reaction time is 18 h to 30 h. The other steps are the same as those in specific embodiments 1 to 4.
[0029] The following examples are used to verify the beneficial effects of the present invention:
[0030] Embodiment 1: A method for preparing a polyacid-derived isometallic sulfide enzyme material is implemented by the following steps:
[0031] 1. Preparation of cobalt-molybdenum-based polyoxometalate precursor: 25.0 mmol of ammonium molybdate was added to 20 mL of distilled water and heated to boiling, and then a mixed solution of 15.0 mmol of cobalt sulfate and 58.8 mmol of hydrogen peroxide was added to the molybdate solution and stirred for reaction for 1 hour, and then the reaction solution was filtered and the filtrate was naturally cooled to room temperature and allowed to stand, thereby obtaining a dark green powder;
[0032] 2. Preparation of cadmium sulfide: 1.2 mmol of cadmium nitrate was dissolved in 10 mL of ethylenediamine and stirred evenly, then 3.7 mmol of thiourea was added to the above solution and stirred evenly, and then the reaction solution was transferred to a 25 mL polytetrafluoroethylene reactor, and then reacted at a temperature of 160°C for 24 hours. After the reaction solution temperature was cooled to room temperature, it was washed to obtain a yellow powder;
[0033] 3. Prepare a polyacid-derived heterometallic sulfide enzyme material: add 0.06g of the cobalt-molybdenum-based polyacid precursor prepared in step one and 0.18g of thiourea to 10mL of distilled water and stir evenly, then add 0.02g of the cadmium sulfide dopant in step two to the above solution and stir evenly, then transfer the reaction solution to a 25mL polytetrafluoroethylene reactor, and then react at 200°C for 24h. After the reaction solution temperature drops to room temperature, wash to obtain a polyacid-derived heterometallic sulfide enzyme material.
[0034] (I) Structural determination of a polyacid-derived heterometallic sulfide enzyme material prepared in Example 1: X-ray powder diffraction pattern as shown in FIG. Figure 3 As shown, the peaks at 2θ angles of 14.11°, 32.83°, and 58.41° correspond to MoS 2 The diffraction peaks at 15.46°, 29.85° and 52.10° are attributed to Co 9 S 8 The peaks at 24.81°, 26.52°, 28.16°, 36.63°, 43.70° and 47.86° correspond to the (100), (002), (101), (102), (110) and (103) planes of CdS. The XRD results verified the successful preparation of the material.
[0035] Figure 1 This is an example - a basic structural unit diagram of a polyacid-derived heterometallic sulfide enzyme material.
[0036] Figure 2 Example - Schematic diagram of the formation process of a polyacid-derived heterometallic sulfide enzyme material
[0037] Figure 3 This is an example - a powder X-ray diffraction pattern of a polyacid-derived heterometallic sulfide enzyme material.
[0038] (ii) X-ray photoelectron measurement of a polyacid-derived heterometallic sulfide enzyme material prepared in Example 1 to obtain an X-ray photoelectron spectrum as follows Figure 4 The spectrum shows that the full measured spectrum of the polyacid-derived heterometallic sulfide enzyme material contains C, O, Cd, Co, Mo and S elements. The high-resolution Mo-3d spectrum shows that the peaks at 228.8 eV and 232.0 eV belong to 1T-MoS 2 Mo in 4+ , the peaks at 229.4 eV and 232.6 eV belong to 2H-MoS 2 Mo in 4+ The peaks at 230.8eV and 233.5eV belong to MoS 2 and oxygen doping defect characteristics. Since oxygen atoms may be due to MoS 2 The oxidative properties are introduced into MoS 2 Therefore, the peak at 235.8eV belongs to the MoO 3 The peak at 226.7 eV was attributed to the S2s peak.
[0039] Figure 4This is an X-ray photoelectron image of an embodiment - a polyacid-derived heterometallic sulfide enzyme material.
[0040] (III) The morphology of the polyacid-derived heterometallic sulfide enzyme material prepared in Example 1 was measured using a scanning electron microscope, and a SEM image of the polyacid-derived heterometallic sulfide enzyme material was obtained as shown in FIG. Figure 5 As shown in the SEM images, the microstructure of polyacid-derived heterometallic sulfides is a flower-like structure formed by the self-assembly of many curved thin sheets with an average diameter of about 2 μm. These nanoflower balls are composed of many vertically crossed nanosheets, and such an arrangement fully exposes the active sites.
[0041] Figure 5 This is a scanning electron micrograph of an embodiment - a polyacid-derived heterometallic sulfide enzyme material.
[0042] (IV) The colorimetric detection performance of a polyacid-derived heterometallic sulfide enzyme material prepared in Example 1 was tested. 2 O 2 The colorimetric detection performance of a polyacid-derived heterometallic sulfide enzyme material was studied by catalyzing the color development reaction of TMB and hydroquinone. 2 -Co 9 S 8 -CdS, hydroquinone (0-80 μM) and H 2 O 2 The volume of the mixed solution was set to 2 mL, and after reacting at room temperature for 10 min, the absorbance of the reaction solution at 652 nm was recorded using a UV-visible spectrophotometer.
[0043] Figure 6 Example - A polyacid-derived heterometallic sulfide enzyme material in H 2 O 2 , UV spectra of TMB and hydroquinone solutions.
[0044] In summary: a polyacid-derived heterometallic sulfide enzyme material of Example 1 was successfully prepared by a hydrothermal synthesis method and was successfully used for colorimetric sensing. The material has good stability and high peroxidase-like activity, and is an enzyme-like catalytic material with excellent performance. It also opens up a new path for the design of multifunctional polyacid-based heterometallic sulfide materials.
Claims
1. A polyacid-derived heterometallic sulfide enzyme material, which appears as a black powder and has the morphology of a nanoflower composed of criss-crossed nanosheets; the main components include 1T / 2H phase MoS2, Co9S8, and CdS.
2. A method for preparing a polyacid-derived heterometallic sulfide enzyme material is accomplished by the following steps:
1. Preparation of cobalt-molybdenum-based polyoxometalate precursor: 30.9 g of ammonium molybdate was added to 20 mL of distilled water and heated to boiling, and then a mixed solution of 4.2 g of cobalt sulfate and 2.0 g of hydrogen peroxide was added to the molybdate solution and stirred for 1 h. The reaction solution was then filtered and the filtrate was naturally cooled to room temperature and allowed to stand, thereby obtaining a dark green powder with a molecular formula of (NH)6Mo7O 24 4H2O; 2. Preparation of cadmium sulfide: 0.39 g of cadmium nitrate was dissolved in 10 mL of ethylenediamine and stirred evenly, then 0.39 g of thiourea was added to the above solution and stirred evenly, and then the reaction solution was transferred to a polytetrafluoroethylene reactor, and then reacted at a temperature of 160°C for 24 hours. After the reaction solution temperature was cooled to room temperature, it was washed to obtain a yellow powder; 3. Prepare a polyacid-derived heterometallic sulfide enzyme material: add the cobalt-molybdenum-based polyacid precursor and thiourea prepared in step one into distilled water and stir evenly, then add the dopant in step two into the above solution and stir evenly, then transfer the reaction solution to a polytetrafluoroethylene reactor, and then react at 200°C for 24 hours. After the reaction solution temperature drops to room temperature, wash to obtain a black powder, which is a polyacid-derived heterometallic sulfide enzyme material.
3. The method for preparing a polyacid-derived heterometallic sulfide enzyme material according to claim 2, characterized in that The metal cobalt salt described in step 1 is cobalt acetate, cobalt nitrate or cobalt chloride.
4. The method for preparing a polyacid-derived isometallic sulfide enzyme material according to claim 2, characterized in that The molar ratio of ammonium molybdate, cobalt sulfate and hydrogen peroxide described in step 1 is 1:(0.5-0.7):(2.25-2.45).
5. The method for synthesizing a polyacid-derived heterometallic sulfide enzyme material according to claim 2, characterized in that The volume ratio of the polyoxometalate precursor described in step 3 to distilled water is 0.04mmol:15mL.
6. The method for synthesizing a polyacid-derived heterometallic sulfide enzyme material according to claim 2, characterized in that The reaction temperature in step 3 is 160-220° C. and the reaction time is 18-30 hours.
7. The performance of a polyacid-derived heterometallic sulfide enzyme material, characterized in that The polyacid-derived heterometallic sulfide prepared with cobalt-molybdenum-based polyoxometallate as a precursor has a morphology of nanoflowers composed of crisscrossed nanosheets and an open surface, forming a nanosheet dual-active surface, so that the polyacid-derived heterometallic sulfide enzyme material has excellent catalytic performance and high enzyme-like activity. In the colorimetric detection of hydroquinone properties experiment, compared with other materials to detect hydroquinone, a polyacid-derived heterometallic sulfide enzyme material has a relatively low detection limit for detecting hydroquinone, and the detection limit of hydroquinone is as low as 0.33 μmol / L; at the same time, a polyacid-derived heterometallic sulfide enzyme material has excellent cyclic stability of simulated enzymes. After at least 3 cycles of experiments, the catalytic activity of a polyacid-derived heterometallic sulfide enzyme material can be maintained at more than 90%, and the composition and structure are almost unchanged.