Preparation method and application of monodisperse copper sulfide quantum dots and nanocomposites thereof
Monodisperse copper sulfide quantum dots were prepared by heating a copper-organosulfur complex, which solved the problems of dispersion and agglomeration of ultra-small copper sulfide particles, achieved good catalytic activity and convenient recovery, and is suitable for peroxidase-like catalysts.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ZHOUKOU NORMAL UNIV
- Filing Date
- 2025-01-13
- Publication Date
- 2026-07-31
AI Technical Summary
Existing technologies struggle to prepare monodisperse, uniformly sized, ultra-small copper sulfide quantum dots, and suffer from poor dispersibility and agglomeration, affecting their enzyme-like catalytic activity and making recovery difficult.
Using a copper-organosulfur complex as a precursor, monodisperse copper sulfide quantum dots were generated through a heating reaction. The particle size was then controlled by adjusting the reaction temperature and the carrier ratio to prepare copper sulfide nanocomposites.
The preparation of monodisperse, uniformly sized copper sulfide quantum dots was achieved, preventing agglomeration, improving catalytic activity, and facilitating recovery. These dots are suitable for peroxidase-like catalysts.
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Figure CN119873874B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of nanomaterials technology, and in particular to a method for preparing monodisperse copper sulfide quantum dots and their nanocomposites, and their applications. Background Technology
[0002] Copper sulfide nanoparticles exhibit good chemical stability, low toxicity, and excellent biocompatibility and photothermal properties, showing promise for applications in antibacterial and tumor treatment. Currently, researchers have prepared copper sulfide nanomaterials with different morphologies, such as nanoparticles, nanosheets, and nanorods, using various synthesis methods including solvothermal, precipitation, thermal decomposition, and template methods. However, reports on ultra-small copper sulfide quantum dots (less than 10 nm) are still relatively few.
[0003] The synthesis of copper sulfide quantum dots is mainly carried out via liquid-phase methods, typically using copper salts, surfactants, and sodium sulfide as raw materials to generate ultra-small copper sulfide nanoparticles in an aqueous phase. For example, the paper "Biodegradable Quantum Composites for Synergistic Photothermal Therapy and Copper-Enhanced Chemotherapy" uses polyvinylpyrrolidone as a surfactant and adds sodium sulfide solution to copper chloride solution to generate water-dispersible copper sulfide quantum dots. However, the CuS quantum dots prepared by this method have a wide size distribution and poor performance.
[0004] Moreover, during the preparation of copper sulfide nanoclusters, due to their small particle size and high surface energy, they are prone to agglomeration into larger nanoparticles, resulting in poor dispersibility. This leads to a decrease in specific surface area and effective active sites, especially after drying, which makes redispersible and reduces their enzyme-like catalytic activity. Highly dispersed ultra-small copper sulfide nanoparticles, on the other hand, present difficulties in separation and recovery, and require further research and improvement. Summary of the Invention
[0005] The purpose of this invention is to provide a method for preparing monodisperse copper sulfide quantum dots and their nanocomposites, and their applications, to solve the aforementioned problems in the background art. This invention uses a copper-organosulfur complex as a precursor and obtains monodisperse, uniformly sized copper sulfide quantum dots through a simple heating process. Furthermore, this invention allows for the control of the particle size of the copper sulfide nanoparticles by adjusting the reaction temperature, and the control of the copper sulfide loading by adjusting the ratio of the copper complex to the support. The prepared copper sulfide nanocomposites exhibit good peroxidase-like catalytic activity.
[0006] To achieve the above objectives, the present invention provides the following technical solution:
[0007] One of the technical solutions of this invention is to provide a method for preparing a monodisperse copper sulfide quantum dot catalyst, comprising the following steps:
[0008] Copper salt and sulfur source are mixed in water to form a precursor solution;
[0009] Ammonia was continuously added to the precursor solution until the reaction system became turbid and then clear. The reaction was carried out, and the solid phase component was collected to obtain the copper sulfide quantum dot precursor.
[0010] The copper sulfide quantum dot precursor was mixed with an organic solvent to obtain a mixture, which was then heated to react and obtain the monodisperse copper sulfide quantum dot catalyst.
[0011] During the addition of ammonia, ammonia needs to be added continuously until the reaction system becomes turbid and then completely clear, in order to avoid the introduction of copper hydroxide impurities into the copper sulfide quantum dot precursor.
[0012] Preferably, the sulfur source is thiamine and / or thiamine salts (vitamin B1); the thiamine salts include one or more of thiamine hydrochloride, thiamine nitrate, and thiamine sulfate; the copper salts include one or more of copper nitrate, copper sulfate, copper chloride, and copper acetate.
[0013] Preferably, the molar ratio of the copper salt to the sulfur source is 1:1 to 1:4, more preferably 3:4 to 1:2.
[0014] Preferably, the reaction time is 1 to 4 hours.
[0015] In the preparation scheme of the present invention, when the amount of copper salt added is too small, the amount of copper sulfide quantum dot precursor generated is too low; when the amount of copper salt added is too large, it will cause copper salt waste. The optimal ratio is 3:4 to 1:2.
[0016] Preferably, the heating reaction temperature is 100–180°C, more preferably 120–140°C, even more preferably 140°C, and the time is 1–6 hours, more preferably 2–4 hours; and / or
[0017] The concentration of copper sulfide quantum dot precursor in the mixture is 10–100 mg / mL, more preferably 40–60 mg / mL; and / or
[0018] The organic solvent is dimethyl sulfoxide or N,N-dimethylformamide.
[0019] When the concentration of copper sulfide quantum dot precursor is too low, the amount of copper sulfide quantum dots generated is small; when the concentration is too high, the particle size of the generated copper sulfide quantum dots will be excessively large.
[0020] The reaction temperature of this invention cannot be too low, otherwise the formation rate of copper sulfide quantum dots will be slow, requiring a longer reaction time.
[0021] More preferably, the preparation of the mixture further includes a step of adding a carrier material; the method for adding the carrier material is to mix the copper sulfide quantum dot precursor, the carrier material and an organic solvent to obtain the mixture.
[0022] More preferably, the carrier material is carbon nitride, silicon dioxide, carbon material or metal oxide; the mass ratio of the copper sulfide quantum dot precursor to the carrier material is 3:1 to 1:5.
[0023] More preferably, the metal oxide is titanium dioxide, aluminum oxide, or cerium oxide.
[0024] The second technical solution of the present invention provides a monodisperse copper sulfide quantum dot catalyst obtained according to the above preparation method.
[0025] The third technical solution of the present invention provides an application of the above-mentioned monodisperse copper sulfide quantum dot catalyst in the field of peroxidase-like catalysts.
[0026] Normally, copper ions in copper salts cannot react with thiamine and its salts (vitamin B1) to form copper complexes, and vitamin B1 is not a sulfur source in the conventional sense. However, under the reaction conditions of this invention, the added ammonia adjusts the solution to alkaline (pH ≥ 9), causing thiamine and its salts to decompose. The carbon-sulfur bond in the thiazole ring breaks, generating a carbonyl group and a sulfonium anion. The carbonyl group then reacts with the amino group on the benzene ring via a Schiff base reaction to form a naphthalene heterocycle. Subsequently, the sulfonium anion can coordinate with copper ions under heating conditions to form CuS nanoclusters (see...). Figure 14 ).
[0027] The beneficial technical effects of the present invention are as follows:
[0028] This invention uses a copper-organosulfur complex as a precursor to obtain monodisperse, uniformly sized copper sulfide quantum dots through a simple heating method. Furthermore, this invention allows for the control of the copper sulfide nanoparticle size by adjusting the reaction temperature, and the adjustment of the copper sulfide loading by regulating the ratio of the copper complex to the support. The prepared copper sulfide nanocomposite material exhibits excellent peroxidase-like catalytic activity.
[0029] This invention loads copper sulfide nanoclusters onto a support material to form a nanocomposite material, which effectively prevents the aggregation of copper sulfide nanoclusters and facilitates the recycling and reuse of the catalyst. When the catalyst is prepared into a nanocomposite product, the particle size of the copper sulfide nanoparticles in the copper sulfide nanocomposite material is 3-8 nm.
[0030] The preparation method of this invention is simple and convenient, and the prepared copper sulfide nanocomposite material can effectively prevent the aggregation of ultra-small copper sulfide nanoparticles, which has great application value. Attached Figure Description
[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0032] Figure 1 The energy spectrum of the copper sulfide quantum dot precursor prepared in Example 1 is shown.
[0033] Figure 2 TEM images of the copper sulfide quantum dots prepared in Example 1 at different magnifications.
[0034] Figure 3 XPS images of copper sulfide quantum dots prepared in Example 1. (a) shows the 2p orbitals of copper, and (b) shows the 2p orbitals of sulfur.
[0035] Figure 4 TEM images of the copper sulfide quantum dots prepared in Example 2 at different magnifications.
[0036] Figure 5 TEM images of the copper sulfide quantum dots prepared in Example 3 at different magnifications.
[0037] Figure 6 TEM images of the copper sulfide nanocomposite material prepared in Example 4 at different magnifications.
[0038] Figure 7 XPS images of the copper sulfide nanocomposite material prepared in Example 4 are shown. In the images, (a) represents the 2p orbitals of copper and (b) represents the 2p orbitals of sulfur.
[0039] Figure 8 The image shows the peroxidase-like properties of the copper sulfide nanocomposite material prepared in Example 4.
[0040] Figure 9 TEM images of the copper sulfide nanocomposite material prepared in Example 5 at different magnifications.
[0041] Figure 10 TEM images of the copper sulfide nanocomposite material prepared in Example 6 at different magnifications.
[0042] Figure 11TEM images of the copper sulfide nanocomposite material prepared in Example 7 at different magnifications.
[0043] Figure 12 TEM images of the copper sulfide nanocomposite material prepared in Example 8 at different magnifications.
[0044] Figure 13 The image shows the peroxidase-like properties of the copper sulfide nanocomposite material prepared in Example 8.
[0045] Figure 14 The reaction formula for preparing copper sulfide quantum dots in this invention is shown below.
[0046] Figure 15 TEM images of the copper sulfide nanocomposite material prepared in Example 9 at different magnifications.
[0047] Figure 16 TEM images of the copper sulfide nanocomposite material prepared in Example 10 at different magnifications.
[0048] Figure 17 TEM images of the copper sulfide nanocomposite material prepared in Example 11 at different magnifications. Detailed Implementation
[0049] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention. It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the present invention.
[0050] Furthermore, regarding the numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, are also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.
[0051] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar to or equivalent to those described herein may be used in the implementation or testing of this invention.
[0052] The terms “comprising,” “including,” “having,” “containing,” etc., used in this invention are all open-ended terms, meaning that they include but are not limited to.
[0053] Figure 14The reaction formula for preparing copper sulfide quantum dots in this invention (taking vitamin B1 as the sulfur source as an example).
[0054] Unless otherwise specified, "room temperature" in this invention refers to 10-30°C.
[0055] The concentration of ammonia water used in the following embodiments of the present invention is between 25 and 28 wt%.
[0056] All raw materials used in the following embodiments of the present invention are commercially available products.
[0057] Example 1
[0058] A method for preparing monodisperse copper sulfide quantum dots, comprising the following steps:
[0059] 6.7 g of thiamine hydrochloride and 1.7 g of copper chloride dihydrate were weighed and dissolved in 200 mL of pure water and stirred until homogeneous to form a precursor solution. Ammonia water was added dropwise to form a light blue precipitate, and then ammonia water was added dropwise until the precipitate was completely dissolved to form a blue copper ammonia solution (during the addition of ammonia water, Cu(OH)2 precipitate was formed first, and with the addition of ammonia water, the precipitate dissolved to form a copper ammonia solution, which was alkaline). The mixture was then stirred for 2 h to allow the reaction system to fully form a yellow copper complex precipitate. The mixture was filtered, washed with pure water, and vacuum dried to obtain a yellow powdery copper sulfide quantum dot precursor.
[0060] Weigh 2.0g of copper sulfide quantum dot precursor and add it to 50mL of dimethyl sulfoxide. After stirring and dissolving, heat the mixture in an oil bath at 140℃ for 4h. Then allow it to cool naturally to room temperature, centrifuge, wash with pure water, and ultrasonically disperse in water to obtain a dispersion of monodisperse copper sulfide quantum dots.
[0061] The copper sulfide quantum dot precursor synthesized in Example 1 was characterized by energy dispersive spectroscopy (EDS) as follows: the copper sulfide quantum dot precursor was deposited on a single-crystal silicon wafer, platinum was deposited using an ion sputtering apparatus, and then EDS was performed using a field emission scanning electron microscope. The results are as follows: Figure 1 As shown.
[0062] Figure 1 The energy spectrum of the copper sulfide quantum dot precursor prepared in Example 1 is shown.
[0063] Depend on Figure 1 It is known that it contains both copper and sulfur.
[0064] The copper sulfide quantum dots prepared in Example 1 were characterized by transmission electron microscopy, such as... Figure 2 As shown.
[0065] Figure 2 TEM images of the copper sulfide quantum dots prepared in Example 1 at different magnifications.
[0066] Depend on Figure 2 It can be seen that the copper sulfide quantum dots prepared in Example 1 have good monodispersity and narrow particle size distribution, with an average particle size of about 3.5 nm.
[0067] The copper sulfide quantum dots prepared in Example 1 were characterized by X-ray photoelectron spectroscopy (XPS), as follows: Figure 3 As shown.
[0068] Figure 3 XPS images of copper sulfide quantum dots prepared in Example 1. (a) shows the 2p orbitals of copper, and (b) shows the 2p orbitals of sulfur.
[0069] Depend on Figure 3 It can be seen that the binding energy peaks of copper at 932.4 eV and 953.2 eV correspond to the 2p phase of divalent copper, respectively. 3 / 2 and 2p 1 / 2 The electron binding energy of sulfur; sulfur exhibits Sg at binding energies of 161.5 eV and 162.7 eV. 2- 2p 3 / 2 and 2p 1 / 2 The electron binding energy peak confirmed that the prepared ultrasmall nanoparticles were copper sulfide quantum dots.
[0070] Example 2
[0071] A method for preparing monodisperse copper sulfide quantum dots, comprising the following steps:
[0072] 3.6 g of thiamine nitrate and 0.6 g of copper nitrate trihydrate were weighed and dissolved in 200 mL of pure water and stirred until homogeneous to form a precursor solution. Ammonia water was added dropwise to form a light blue precipitate, and then ammonia water was added dropwise until the precipitate was completely dissolved to form a blue copper ammonia solution. The solution was then stirred for 4 h, filtered, washed with pure water, and dried under vacuum to obtain a yellow powdery copper sulfide quantum dot precursor.
[0073] Weigh 0.5g of copper sulfide quantum dot precursor and add it to 50mL of dimethyl sulfoxide. After stirring and dissolving, heat the mixture in an oil bath at 160℃ for 2h, then allow it to cool naturally to room temperature. Centrifuge, wash with pure water, and ultrasonically disperse in water to obtain a dispersion of monodisperse copper sulfide quantum dots.
[0074] Figure 4 TEM images of the copper sulfide quantum dots prepared in Example 2 at different magnifications.
[0075] like Figure 4 As shown, copper sulfide quantum dots exhibit good monodispersity, with a particle size distribution mainly between 4 and 8 nm and an average particle size of approximately 6.6 nm.
[0076] Example 3
[0077] A method for preparing monodisperse copper sulfide quantum dots, comprising the following steps:
[0078] 10g of thiamine hydrochloride and 5g of copper sulfate pentahydrate were weighed and dissolved in 250mL of pure water and stirred evenly to form a precursor solution. Ammonia water was added dropwise to form a light blue precipitate. Ammonia water was then added dropwise until the precipitate was completely dissolved to form a blue copper ammonia solution. The solution was stirred for 3 hours, filtered, washed with pure water, and dried under vacuum to obtain a yellow powdery copper sulfide quantum dot precursor.
[0079] Weigh 1g of copper sulfide quantum dot precursor and add it to 20mL of N,N-dimethylformamide. After stirring and dissolving, heat the mixture in an oil bath at 100℃ for 6h. Then, allow it to cool naturally to room temperature, centrifuge, wash with pure water, and ultrasonically disperse it in water to obtain a dispersion of monodisperse copper sulfide quantum dots.
[0080] Figure 5 TEM images of the copper sulfide quantum dots prepared in Example 3 at different magnifications.
[0081] like Figure 5 As shown, copper sulfide quantum dots exhibit good monodispersity with an average particle size of approximately 2.6 nm.
[0082] Example 4
[0083] A method for preparing a copper sulfide nanocomposite material, comprising the following steps:
[0084] 3.4 g of thiamine hydrochloride and 1.25 g of copper sulfate pentahydrate were weighed and dissolved in 50 mL of pure water and stirred evenly to form a precursor solution. Ammonia water was added dropwise to form a light blue precipitate. Ammonia water was then added dropwise until the precipitate was completely dissolved to form a blue copper ammonia solution. The solution was stirred for 2 hours, filtered, washed with pure water, and dried under vacuum to obtain a yellow powdery copper sulfide quantum dot precursor.
[0085] 0.5 g of copper sulfide quantum dot precursor was weighed and added to 10 mL of dimethyl sulfoxide to obtain a copper complex solution. 2.5 g of graphitic carbon nitride (g-C3N4) was weighed and ultrasonically dispersed in 75 mL of dimethyl sulfoxide to form a dispersion. The copper complex solution was added to the dispersion under stirring. After stirring for 30 min, the mixture was heated in an oil bath at 180 °C for 1 h, then allowed to cool naturally to room temperature. The mixture was then centrifuged, washed with pure water, and the resulting graphitic carbon nitride-supported copper sulfide nanocomposite material (CuS@g-C3N4) was obtained.
[0086] Figure 6 TEM images of the copper sulfide nanocomposite material prepared in Example 4 at different magnifications.
[0087] like Figure 6 As shown, ultra-small copper sulfide nanoparticles are uniformly distributed on the surface of g-C3N4, with an average particle size of about 8 nm.
[0088] Figure 7 XPS images of the copper sulfide nanocomposite material prepared in Example 4 are shown. In the images, (a) represents the 2p orbitals of copper and (b) represents the 2p orbitals of sulfur.
[0089] Figure 7 In this composition, copper is predominantly +2 in oxidation state, while sulfur is -2; the atomic fractions of copper and sulfur are 6.26% and 7.16%, respectively.
[0090] Example 1
[0091] Weigh 10 mg of CuS@g-C3N4 prepared in Example 4 and ultrasonically disperse it in 5 mL of water to prepare a CuS@g-C3N4 dispersion. Take 0.5 mL of acetate-sodium acetate buffer solution (0.2 mol / L, pH=4) in a test tube, then add 10 μL of 3,3',5,5'-tetramethylbenzidine (50 mmol / L), 10 μL of hydrogen peroxide solution (250 mmol / L), and 10 μL of CuS@g-C3N4 dispersion. Shake well and react for 10 min. The solution turns dark blue. Figure 8 The third test tube from the left is labeled TMB+CuS@g-C3N4+H2O2). Dispersions without CuS@g-C3N4 were prepared separately. Figure 8 The test tube on the left is labeled TMB + H2O2 and hydrogen peroxide-free ( ). Figure 8 The second test tube from the left, labeled as TMB+CuS@g-C3N4, served as the control group. The control experiment showed no obvious phenomenon, indicating that the CuS@g-C3N4 nanocomposite material prepared in Example 4 has peroxidase-like activity.
[0092] Figure 8 The image shows the peroxidase-like properties of the copper sulfide nanocomposite material prepared in Example 4.
[0093] Figure 8 In the middle, the first, second, and third test tubes from the left contain TMB+H2O2, TMB+CuS@g-C3N4, and TMB+CuS@g-C3N4+H2O2, respectively.
[0094] Example 5
[0095] A method for preparing a copper sulfide nanocomposite material, comprising the following steps:
[0096] 3.4 g of thiamine hydrochloride and 1.25 g of copper sulfate pentahydrate were weighed and dissolved in 50 mL of pure water and stirred evenly to form a precursor solution. Ammonia water was added dropwise to form a light blue precipitate. Ammonia water was then added dropwise until the precipitate was completely dissolved to form a blue copper ammonia solution. The solution was stirred for 2 hours, filtered, washed with pure water, and dried under vacuum to obtain a yellow powdery copper sulfide quantum dot precursor.
[0097] 0.5 g of copper sulfide quantum dot precursor was weighed and added to 10 mL of dimethyl sulfoxide to obtain a copper complex solution. 0.75 g of cerium dioxide (CeO2) was weighed and ultrasonically dispersed in 75 mL of dimethyl sulfoxide to form a dispersion. The copper complex solution was added to the dispersion under stirring. After stirring for 30 min, the mixture was heated in an oil bath at 140 °C for 4 h, then allowed to cool naturally to room temperature. The mixture was then centrifuged, washed with pure water, and the cerium dioxide-supported copper sulfide nanocomposite material (CuS@CeO2) was obtained.
[0098] Figure 9 TEM images of the copper sulfide nanocomposite material prepared in Example 5 at different magnifications.
[0099] like Figure 9 As shown, ultra-small copper sulfide nanoparticles can be clearly seen coating the CeO2 surface, with an average particle size of about 3-5 nm.
[0100] Example 6
[0101] A method for preparing a copper sulfide nanocomposite material, comprising the following steps:
[0102] 6.8 g of thiamine hydrochloride and 1.7 g of copper chloride hydrate were weighed and dissolved in 50 mL of pure water and stirred evenly to form a precursor solution. Ammonia water was added dropwise to form a light blue precipitate. Ammonia water was then added dropwise until the precipitate was completely dissolved to form a blue copper ammonia solution. The solution was stirred for 4 h, filtered, washed with pure water, and dried under vacuum to obtain a yellow powdery copper sulfide quantum dot precursor.
[0103] 1.0 g of copper sulfide quantum dot precursor was weighed and added to 20 mL of N,N-dimethylformamide (DMF) to obtain a copper complex solution. 1.0 g of carbon black nanoparticles (XC-72) was weighed and ultrasonically dispersed in 50 mL of DMF to form a dispersion. The copper complex solution was added to the dispersion under stirring. After stirring for 1 h, the mixture was heated in an oil bath at 140 °C for 4 h, then allowed to cool naturally to room temperature. The mixture was then centrifuged, washed with pure water, and the carbon black-supported copper sulfide nanocomposite material (CuS@XC-72) was obtained.
[0104] Figure 10 TEM images of the copper sulfide nanocomposite material prepared in Example 6 at different magnifications.
[0105] like Figure 10 As shown, ultra-small copper sulfide nanoparticles are uniformly distributed on the surface of XC-72, with an average particle size of about 4 nm.
[0106] Example 7
[0107] A method for preparing a copper sulfide nanocomposite material, comprising the following steps:
[0108] 6.8 g of thiamine hydrochloride and 1.7 g of copper chloride hydrate were weighed and dissolved in 50 mL of pure water and stirred evenly to form a precursor solution. Ammonia water was added dropwise to form a light blue precipitate. Ammonia water was then added dropwise until the precipitate was completely dissolved to form a blue copper ammonia solution. The solution was stirred for 4 h, filtered, washed with pure water, and dried under vacuum to obtain a yellow powdery copper sulfide quantum dot precursor.
[0109] 1.0 g of copper sulfide quantum dot precursor was weighed and added to 20 mL of dimethyl sulfoxide to obtain a copper complex solution. 2.0 g of nano-alumina (Al₂O₃) was weighed and ultrasonically dispersed in 100 mL of dimethyl sulfoxide to form a dispersion. The copper complex solution was added to the dispersion under stirring. After stirring for 30 min, the mixture was heated in an oil bath at 160 °C for 3 h, then allowed to cool naturally to room temperature. The mixture was then centrifuged, washed with pure water, and the cerium dioxide-supported copper sulfide nanocomposite material (CuS@Al₂O₃) was obtained.
[0110] Figure 11 TEM images of the copper sulfide nanocomposite material prepared in Example 7 at different magnifications.
[0111] like Figure 11 As shown, ultra-small copper sulfide nanoparticles are uniformly distributed on the Al2O3 surface, with an average particle size of about 8 nm.
[0112] Example 8
[0113] A method for preparing a copper sulfide nanocomposite material, comprising the following steps:
[0114] 6.8 g of thiamine hydrochloride and 1.7 g of copper chloride hydrate were weighed and dissolved in 50 mL of pure water and stirred evenly to form a precursor solution. Ammonia water was added dropwise to form a light blue precipitate. Ammonia water was then added dropwise until the precipitate was completely dissolved to form a blue copper ammonia solution. The solution was stirred for 4 h, filtered, washed with pure water, and dried under vacuum to obtain a yellow powdery copper sulfide quantum dot precursor.
[0115] 0.3 g of copper sulfide quantum dot precursor was weighed and added to 10 mL of dimethyl sulfoxide to obtain a copper complex solution. 0.1 g of graphene oxide (GO) was weighed and ultrasonically dispersed in 20 mL of dimethyl sulfoxide to form a dispersion. The copper complex solution was added to the dispersion under stirring. After stirring for 30 min, the mixture was heated in an oil bath at 140 °C for 4 h, then allowed to cool naturally to room temperature. The mixture was then centrifuged, washed with pure water, and the resulting graphene oxide-supported copper sulfide nanocomposite material (CuS@GO) was obtained.
[0116] Figure 12 TEM images of the copper sulfide nanocomposite material prepared in Example 8 at different magnifications.
[0117] Example 2
[0118] Weigh 10 mg of CuS@GO prepared in Example 8 and ultrasonically disperse it in 10 mL of water to prepare a CuS@GO dispersion. Take 0.5 mL of acetate-sodium acetate buffer solution (0.2 mol / L, pH=4) in a test tube, then add 10 μL of 3,3',5,5'-tetramethylbenzidine (50 mmol / L), 10 μL of hydrogen peroxide solution (250 mmol / L), and 10 μL of CuS@GO dispersion. Shake well and react for 10 min. The solution turns dark blue. Figure 13 The third test tube from the left is labeled TMB + CuS@GO + H2O2. A CuS@GO-free dispersion was prepared separately. Figure 13 The test tube on the left is labeled TMB + H2O2 and hydrogen peroxide-free ( ). Figure 13 The second test tube from the left, labeled as the TMB+CuS@GO test group, served as a control. The control experiment showed no obvious phenomena, indicating that the CuS@GO nanocomposite material prepared in Example 8 has peroxidase-like activity.
[0119] Figure 13 The image shows the peroxidase-like properties of the copper sulfide nanocomposite material prepared in Example 8.
[0120] Figure 13 In the middle, the first, second, and third test tubes from the left contain TMB+H2O2, TMB+CuS@GO, and TMB+CuS@GO+H2O2, respectively.
[0121] Example 9
[0122] The only difference from Example 6 is that the oil bath heating temperature is changed to 160°C.
[0123] Example 10
[0124] The only difference from Example 9 is that the amount of copper sulfide quantum dot precursor added is changed to 1.5g.
[0125] Example 11
[0126] The only difference from Example 9 is that the amount of copper sulfide quantum dot precursor added is changed to 2.0g.
[0127] Figure 15 TEM images of the copper sulfide nanocomposite material prepared in Example 9 at different magnifications.
[0128] Figure 16 TEM images of the copper sulfide nanocomposite material prepared in Example 10 at different magnifications.
[0129] Figure 17TEM images of the copper sulfide nanocomposite material prepared in Example 11 at different magnifications.
[0130] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.
Claims
1. A method for preparing monodispersed copper sulfide quantum dot type catalysts, characterized by, Includes the following steps: Copper salt and sulfur source are mixed in water to form a precursor solution; Ammonia was continuously added to the precursor solution until the reaction system became turbid and then clear. The reaction was carried out, and the solid phase component was collected to obtain the copper sulfide quantum dot precursor. The copper sulfide quantum dot precursor was mixed with an organic solvent to obtain a mixture, which was then heated to react and obtain the monodisperse copper sulfide quantum dot catalyst. The sulfur source is thiamine and / or thiamine salts; the thiamine salts include one or more of thiamine hydrochloride, thiamine nitrate, and thiamine sulfate; the copper salts include one or more of copper nitrate, copper sulfate, copper chloride, and copper acetate. The molar ratio of the copper salt to the sulfur source is 1:1 to 1:4; The reaction time is 1-4 hours; The heating reaction is carried out at a temperature of 100~180℃ for 1~6 hours. The concentration of copper sulfide quantum dot precursor in the mixture is 10~100 mg / mL; The organic solvent is dimethyl sulfoxide or N,N-dimethylformamide.
2. The production method according to claim 1, characterized by, The preparation of the mixture also includes the step of adding a carrier material; the method for adding the carrier material is as follows: mixing the copper sulfide quantum dot precursor, the carrier material and an organic solvent to obtain the mixture.
3. The preparation method according to claim 2, characterized in that, The carrier material is carbon nitride, silicon dioxide, carbon material, or metal oxide; the mass ratio of the copper sulfide quantum dot precursor to the carrier material is 3:1 to 1:
5.
4. A monodisperse copper sulfide quantum dot catalyst obtained by the preparation method according to any one of claims 1-3.
5. The application of a monodisperse copper sulfide quantum dot catalyst according to claim 4 in the field of peroxidase-like catalysts.