CN111715891A

CN111715891A - Copper nanoparticle solution and preparation method and application thereof

Info

Publication number: CN111715891A
Application number: CN202010608933.4A
Authority: CN
Inventors: 李林; 陈娟; 杨凡; 张彩凤
Original assignee: Taiyuan Normal University
Current assignee: Taiyuan Normal University
Priority date: 2020-06-29
Filing date: 2020-06-29
Publication date: 2020-09-29
Anticipated expiration: 2040-06-29
Also published as: CN111715891B

Abstract

The invention discloses a copper nanoparticle solution and a preparation method and application thereof. The preparation method of the copper nanoparticle solution comprises the following steps: respectively preparing aqueous solutions of copper chloride, 2-mercaptobenzothiazole and polyvinylpyrrolidone, mixing the aqueous solutions, adding hydrazine hydrate, and standing the solution at 10-20 ℃ to obtain a strong orange fluorescent emission copper nanoparticle solution. The copper nanoparticle solution probe prepared by the invention has strong stability, can be used for detecting silver ions, is applied to silver ion detection test paper, and can be used for visualizing the detection of the silver ions. The copper nanoparticle solution of the present invention can also be used for pattern dyeing fabrication.

Description

Copper nanoparticle solution and preparation method and application thereof

Technical Field

The invention relates to the technical field of metal nanoparticles, in particular to a copper nanoparticle solution and a preparation method and application thereof.

Background

Silver ions have the characteristics of bacteriostasis, disinfection, inflammation diminishing and the like, and are widely applied to the aspects of production, life, medicine and the like, such as silver ion washing machines, silver ion refrigerators and the like. But the excessive use of silver ions can cause life threat and serious pollution to human bodies and the environment. Such as: excessive intake and long-term accumulation of silver ions can lead to insoluble precipitates in eyes and skin, can also lead to degenerative changes such as inactivation of normal functions of mercaptoenzymes, human anemia, growth retardation, heart enlargement and the like, can also cause microorganisms to die by suffocation, and has toxicity to certain bacteria, viruses, algae and fungi and causes pollution to environmental drinking water. Therefore, the silver ion detection method with high selectivity, high sensitivity and strong anti-interference performance is very important for human health, biomedicine and environmental protection.

The fluorescent ion probe is one of fluorescent probes, and can convert molecule/ion binding information into a fluorescent signal which is easy to detect, so as to obtain an ion recognition function. As a sensitive detection means with wide application value, the fluorescent ion probe has the advantages that the traditional methods such as atomic absorption spectroscopy, ion selective electrode analysis and the like cannot compare with other molecular methods, namely, the existence of ions can be visually reflected through the change of fluorescence intensity or emission peak wavelength, and the fluorescent ion probe has high sensitivity. Silver ion chemical sensors based on fluorescent probes have become a focus of research in recent years. 3, 4-bis-triazine bodipy, as proposed by Kursunlu et al, was used as a sensor for the detection of silver ions.

Although the number of fluorescent probes applied to silver ion detection is increasing, the fluorescent probes still have many defects, such as poor detection limit, complex synthetic procedure, interference of other transition metal ions, long response time and use of organic solvents. And most of silver ion fluorescent probes take rhodamine and pyrene as main structures, and have larger environmental hazard in the production and application processes. Therefore, it is necessary to develop a silver ion fluorescent probe with fast response, high sensitivity, high selectivity and low environmental hazard.

Disclosure of Invention

The invention aims to provide a preparation method of a copper nanoparticle solution, which aims to solve the problems in the prior art, and has the advantages of simple operation and mild and quick reaction conditions; the prepared nano-particles can be applied to the preparation of fluorescent probes for detecting silver ions and pattern dyeing.

In order to achieve the purpose, the invention provides the following scheme: the invention provides a copper nanoparticle solution, which is prepared by taking copper chloride as a copper precursor, polyvinylpyrrolidone as a protective agent, 2-mercaptobenzothiazole as a stabilizing agent and hydrazine hydrate as a reducing agent through standing at room temperature.

The invention also provides a preparation method of the copper nanoparticle solution, which comprises the following steps:

(1) respectively preparing a copper chloride solution, a 2-mercaptobenzothiazole solution and a polyvinylpyrrolidone solution, and sequentially adding the copper chloride solution, the 2-mercaptobenzothiazole solution and the polyvinylpyrrolidone solution into a 25ml colorimetric tube according to the volume ratio of 1: 1-9: 2-17 to form a mixed solution;

(2) then adding 0.2-1.5 mL of hydrazine hydrate with the molar concentration of 10.28M, then fixing the volume to 25.0mL, shaking up, and dropwise adding 1.0M of HCl or NaOH to adjust the pH value of the mixed solution;

(3) and (3) standing the solution obtained in the step (2) at 10-20 ℃ for 10-30 minutes, and then dialyzing and purifying the mixed solution by using a dialysis bag with the molecular weight cutoff of 3500 to obtain a colorless polyvinylpyrrolidone-copper nanoparticle fluorescent probe aqueous solution, and storing the colorless polyvinylpyrrolidone-copper nanoparticle fluorescent probe aqueous solution in a refrigerator at 4 ℃ in a dark place. The prepared copper nanoparticle solution is colorless under the irradiation of a fluorescent lamp and orange under the irradiation of a 365nm ultraviolet lamp.

As a further optimization of the invention, in the step (1), the concentration of the copper chloride solution is 1.0mM, the concentration of the polyvinylpyrrolidone solution is 0.07mM, and the concentration of the 2-mercaptobenzothiazole solution is 10.0 mM.

As a further optimization of the invention, the volume ratio of the copper chloride solution, the 2-mercaptobenzothiazole solution and the polyvinylpyrrolidone solution in the step (1) is 1:5: 10.

As a further optimization of the invention, the amount of hydrazine hydrate added in step (2) is 0.4 mL.

As a further optimization of the invention, the pH value of the solution system in the step (2) is 12.0-14.0.

As a further optimization of the invention, in step (3), the temperature is 15 ℃ and the standing time is 10 minutes.

The invention provides application of the copper nanoparticle solution in silver ion detection.

The invention also provides application of the copper nanoparticle solution in pattern dyeing manufacture. The pattern made by CuNPs @ PVP/MBT/HYD solution realizes visualization under 365nm excitation. This "invisible" nature of the CuNPs @ PVP/MBT/HYD pattern is beneficial for other applications such as in the anti-counterfeiting field as well as in optoelectronic devices.

Due to its unique physicochemical properties, copper nanoclusters are widely used in bioanalysis, bioimaging, environmental detection, industrial catalysis, and electronics. In order to obtain the copper nanocluster with high selectivity and capable of accurately detecting silver ions, copper chloride is used as a raw material, polyvinylpyrrolidone is used as a protective agent, 2-mercaptobenzothiazole is used as a stabilizing agent, and hydrazine hydrate is used as a reducing agent, so that the copper nanoparticle solution with orange fluorescence is synthesized. The method is convenient and quick, is simple to operate, can quickly respond and can detect the silver ions with high selectivity.

The invention discloses the following technical effects:

1. compared with the prior art, the fluorescent copper nanoparticle solution has the characteristics of short reaction time, standing only for operation, no need of complicated operations such as stirring ultrasound and the like, environmental friendliness, economy, easiness and the like.

2. The fluorescent copper nanoparticle solution can be used for visualizing the detection of silver ions by manufacturing silver ion test paper.

3. The copper nanoparticle solution prepared by the invention has high sensitivity and strong selectivity to silver ions, and can be used for constructing and detecting Ag⁺The ion chemical sensing system has simple detection means and accurate detection result.

4. The fluorescent copper nanoparticle solution prepared by the invention has good orange luminescence property and has wide application prospect in the fields of biological imaging, pattern dyeing and manufacturing and the like.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise.

FIG. 1 is a schematic diagram of the synthesis and application of copper nanoparticles according to the present invention;

FIG. 2(A) is a diagram showing an ultraviolet-visible absorption spectrum and a fluorescence excitation and emission spectrum of the copper nanoparticle solution prepared in example 1; (B) is a fluorescence spectrum diagram of the copper nanoparticle solution and the reactant; (C) is a UV-visible absorption spectrum diagram of the copper nanoparticle solution and the reactant;

FIG. 3 is a transmission electron micrograph of copper nanoparticles in a copper nanoparticle solution according to example 1;

FIG. 4A is an XPS plot of copper nanoparticles in the copper nanoparticle solution of example 1, and FIG. 4B is an XPS plot of Cu 2p in the copper nanoparticle solution;

FIG. 5 is the salt tolerance of the copper nanoparticle solution of example 1;

FIG. 6 shows the selectivity of the copper nanoparticle solution of example 1 for detecting silver ions;

FIG. 7 is a graph (A) showing the fluorescence spectra and a linear relationship (B) between the copper nanoparticle solution of example 1 and silver ions of different concentrations;

FIG. 8 is a fluorescent chart of a pattern produced by solution dyeing of copper nanoparticles according to example 1;

FIG. 9 is a fluorescence spectrum of the copper nanoparticle solution synthesized in examples 1 to 5;

FIG. 10 is a fluorescence spectrum of the copper nanoparticle solutions synthesized in example 1 and examples 6 to 9;

FIG. 11 is a fluorescence spectrum of the copper nanoparticle solutions synthesized in example 1 and examples 10 to 13;

FIG. 12 is a fluorescence spectrum of the copper nanoparticle solutions synthesized in example 1 and examples 14 to 17;

FIG. 13 is a fluorescence spectrum of a copper nanoparticle solution synthesized in example 1 and examples 18 to 21;

FIG. 14 is a fluorescence spectrum of a copper nanoparticle solution synthesized in example 1 and examples 22 to 30;

FIG. 15 is a fluorescence spectrum of a copper nanoparticle solution synthesized in example 1 and examples 31 to 34.

Detailed Description

Reference will now be made in detail to various exemplary embodiments of the invention, the detailed description should not be construed as limiting the invention but as a more detailed description of certain aspects, features and embodiments of the invention.

It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Further, for numerical ranges in this disclosure, it is understood that each intervening value, between the upper and lower limit of that range, is also specifically disclosed. Every smaller range between any stated value or intervening value in a stated range and any other stated or intervening value in a stated range is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference herein for the purpose of disclosing and describing the methods and/or materials associated with the documents. In case of conflict with any incorporated document, the present specification will control.

It will be apparent to those skilled in the art that various modifications and variations can be made in the specific embodiments of the present disclosure without departing from the scope or spirit of the disclosure. Other embodiments will be apparent to those skilled in the art from consideration of the specification. The specification and examples are exemplary only.

As used herein, the terms "comprising," "including," "having," "containing," and the like are open-ended terms that mean including, but not limited to.

Cupric chloride dihydrate (CuCl)₂·2H₂O, molecular weight 170.5) is produced by Tianjin's Tianli chemical reagent, Inc.

2-mercaptobenzothiazole (C)₇H₅NS₂Molecular weight of 167.24) was produced by Shanghai Aladdin reagent, Inc.

Polyvinylpyrrolidone ((C)₆H₉NO)_nMolecular weight of 58000) was produced by Shanghai Mecline Bioreagent, Inc.

Hydrazine hydrate (N)₂H₄·H₂O, molecular weight 50.06) is produced by Tianjin Deng peaking chemical reagent factory.

Sodium ion Na⁺Potassium ion K⁺Ni ion Ni²⁺Lead ion Pb²⁺Barium ion Ba²⁺Cadmium ion Cd²⁺Strontium ion Sr² ⁺Magnesium ion Mg²⁺Zinc ion Zn²⁺Mn ion Mn²⁺Calcium ion Ca²⁺Aluminum ion Al³⁺Iron ion Fe³⁺Copper ion Cu²⁺Mercury ion Hg²⁺Silver ion Ag⁺Is produced by chemical reagent three factories in Tianjin.

The water used in the invention is 18.2M omega ultrapure water.

Example 1:

preparation of copper nanoparticle solution

The novel method for preparing the orange fluorescent copper nanoparticles by using polyvinylpyrrolidone as a protective agent, 2-mercaptobenzothiazole as a stabilizing agent and hydrazine hydrate as a reducing agent has a reaction schematic diagram shown in figure 1:

(1) accurately weighing copper chloride, and dissolving with ultrapure water to obtain 1.0mM CuCl₂An aqueous solution; accurately weighing 2-mercaptobenzothiazole, and dissolving the 2-mercaptobenzothiazole by using a 1.0M NaOH solution to prepare a 10.0mM 2-mercaptobenzothiazole solution; accurately weighing polyvinylpyrrolidone, dissolving with ultrapure water to obtain polyvinylpyrrolidone with concentration of 0.07mM, sequentially transferring copper chloride solution 1.0mL, polyvinylpyrrolidone solution 10.0mL, and 2-mercaptobenzothiophene5.0mL of oxazole solution was placed in a clean, dry 25.0mL cuvette.

(2) Adding 0.4mL of hydrazine hydrate stock solution into the solution obtained in the step (1), then diluting to 25.0mL of volume and shaking up, and adjusting the pH value to 13.45;

(3) and (3) standing the mixed solution obtained in the step (2) for 10min at 15 ℃, dialyzing and purifying the mixed solution by using a dialysis bag with the molecular weight cutoff of 3500 to obtain a colorless polyvinylpyrrolidone-copper nanoparticle fluorescent probe aqueous solution, and storing the colorless polyvinylpyrrolidone-copper nanoparticle fluorescent probe aqueous solution in a refrigerator at 4 ℃ in a dark place, namely CuNPs @ PVP/MBT/HYD.

In this example, the concentration of polyvinylpyrrolidone in the solution system in the step (2) is 28 μ M; the concentration of the 2-mercaptobenzothiazole in the solution system is 2.0 mM.

The prepared copper nanoparticle solution is colorless under the irradiation of a fluorescent lamp and orange under the irradiation of a 365nm ultraviolet lamp.

In order to confirm whether the orange fluorescent copper nanoparticles, namely CuNPs @ PVP/MBT/HYD, are successfully prepared, CuNPs @ PVP/MBT/HYD solution and a control sample CuCl are respectively taken₂PVP, MBT and HYD solutions, the corresponding ultraviolet and fluorescence spectra were measured in a quartz cuvette and the results are shown in figure 2. FIG. 2 shows the UV absorption spectrum of CuNPs @ PVP/MBT/HYD with UV absorption peak around 370nm, and the fluorescence spectrum shows the optimal emission peak at 590nm under 370nm excitation.

In order to confirm the morphology and size of CuNPs @ PVP/MBT/HYD, the CuNPs @ PVP/MBT/HYD solution is ultrasonically dropped on a copper net for half an hour to prepare a sample, and when the liquid volatilizes, the sample is observed by a transmission electron microscope. In addition, the sonicated CuNPs @ PVP/MBT/HYD liquid was placed in a Malvern particle sizer to measure particle size, the results are shown in FIG. 3. FIG. 3 is a transmission electron microscopy analysis spectrogram of the prepared CuNPs @ PVP/MBT/HYD, which shows that the prepared CuNPs @ PVP/MBT/HYD is uniformly dispersed and spherical, the average size is about 10.0-15.0nm, and the inset is a particle size analysis spectrogram of the prepared CuNPs @ PVP/MBT/HYD, which is consistent with the results of a lens electron microscopy.

To confirm the elements constituting CuNPs @ PVP/MBT/HYD in this example, the prepared liquid sample was freeze-dried to obtain a solid, which was then characterized on an X-ray photoelectron analyzer, and the results are shown in FIG. 4. FIG. 4A is a graph of CuNPs @ PVP/MBT/HYD and XPS, which shows that CuNPs @ PVP/MBT/HYD is composed of five elements of Cu, C, N, O and S. XPS spectra of Cu 2p in FIG. 4B confirmed the presence of two distinct peaks for Cu 2p1/2 and Cu 2p3/2, one at 951.65eV and the other at 931.73eV, assigned to Cu (0) and Cu (I), respectively.

To investigate the effect of ionic strength on the fluorescence intensity of CuNPs @ PVP/MBT/HYD prepared in this example, 200. mu.L of the CuNPs @ PVP/MBT/HYD solution was diluted with 1.8mL (0.05M, 0.1M, 0.2M, 0.25M, 0.5M) NaCl solution, respectively, and the fluorescence spectra at an excitation wavelength of 370nm and an emission wavelength of 590nm was measured. The results are shown in fig. 12, the CuNPs @ PVP/MBT/HYD fluorescence intensity shows an enhancement trend in the range of 0.05M to 0.5M of the NaCl solution, but the overall stability is relatively high, which indicates that the copper nanoparticles of the present invention have good salt tolerance.

Fluorescence studies of the interaction of various ions with CuNPs @ PVP/MBT/HYD synthesized in this example. 0.01M of each ionic solution (Na) was prepared⁺、K⁺、Ni²⁺、Pb²⁺、Ba²⁺、Cd²⁺、Sr²⁺、Mg²⁺、Zn²⁺、Mn²⁺、Ca²⁺、Al³⁺、Fe³⁺、Cu²⁺、Hg²⁺、Ag⁺) 1.0mL of the prepared CuNPs @ PVP/MBT/HYD solution was diluted with 9.0mL of Tris-HCl solution (pH 4.5). Setting parameters of a fluorescence spectrometer (lambda ex is 370nm, lambda em is 500nm-610nm), placing 2.0mL in a fluorescence cuvette to scan a sample, and recording data; and adding 10 mu L of the cation solution into a fluorescent cup, stirring, timing for 2.0min, scanning a sample, and recording data. FIG. 6 records the results of the experiment, which demonstrate that Ag⁺Can quench the fluorescence of CuNPs @ PVP/MBT/HYD, and other cations have almost no influence on the fluorescence of CuNPs @ PVP/MBT/HYD.

Fluorescence study of interaction of silver ions and CuNPs @ PVP/MBT/HYD synthesized in the example A plurality of 2.0mL EP tubes were taken, numbered, and Ag with different concentrations was prepared⁺And (3) solution. 2.0mL of the prepared CuNPs @ PVP/MBT/HYD solution was added into a fluorescence cup with 10.0 μ L of Ag with different concentrations⁺Solution (final concentration 2.5-125. mu.M) is addedAfter stirring, the time was taken for 2min, the sample was scanned and the data recorded. FIG. 7A shows the results with Ag⁺The concentration of the solution is increased, the fluorescence intensity of CuNPs @ PVP/MBT/HYD is gradually weakened when Ag⁺When the solution concentration increased to 125. mu.M, the fluorescence of CuNPs @ PVP/MBT/HYD was completely quenched. Shows that the orange fluorescent copper nanoparticles prepared by the invention can realize the effect on Ag⁺Detection of (3). FIG. 7B results illustrate the change in the fluorescence intensity of CuNPs @ PVP/MBT/HYD with Ag⁺The concentration shows a good linear relationship, and shows two linear relationships, respectively F₀-F＝194.1323+32.3836C(R²0.9824) and F₀-F＝20.4519C-1.0329(R²0.9969), linear range of 2.5-125 μ M, detection limit of 250nM, indicating CuNPs @ PVP/MBT/HYD prepared versus Ag⁺Has better response and sensitivity.

This example is made by dyeing a CuNPs @ PVP/MBT/HYD pattern. Manually folding patterns such as snowflakes and the like by using filter paper, and then soaking the filter paper with the patterns into CuNPs @ PVP/MBT/HYD solution. After drying, the mixture is placed in a dark box ultraviolet instrument and is irradiated under a 365nm ultraviolet lamp for observation and photographing, and the result is shown in figure 8. FIG. 8 shows the clear orange fluorescence. It is clear that these patterns made with the CuNPs @ PVP/MBT/HYD solution were visualized at 365nm excitation. This "invisible" nature of the CuNPs @ PVP/MBT/HYD pattern is beneficial for other applications such as in the anti-counterfeiting field as well as in optoelectronic devices.

Example 2

In the same manner as in example 1, 2.0mL of the polyvinylpyrrolidone solution was added only in step (2), and the concentration of polyvinylpyrrolidone in the solution system was adjusted to 5.6. mu.M.

Example 3

In the same manner as in example 1, only 6.0mL of the polyvinylpyrrolidone solution was added in step (2), and the concentration of polyvinylpyrrolidone in the solution system was adjusted to 16.8. mu.M.

Example 4

In the same manner as in example 1, 15.0mL of the polyvinylpyrrolidone solution was added only in step (2), and the concentration of polyvinylpyrrolidone in the solution system was adjusted to 33.6. mu.M.

Example 5

In the same manner as in example 1, 17.0mL of the polyvinylpyrrolidone solution was added only in step (2), and the concentration of polyvinylpyrrolidone in the solution system was adjusted to 42. mu.M.

Then, the CuNPs @ PVP/MBT/HYD solution prepared in the embodiment 1-5 is detected by a fluorescence spectrometer, and the result is shown in FIG. 9, wherein when the addition amount of the polyvinylpyrrolidone solution is 10ml, and the final concentration is 28 μ M, the fluorescence intensity of the synthesized CuNPs @ PVP/MBT/HYD solution is the maximum.

Example 6

In this example, the same technical scheme as that of example 1 was adopted, except that 1.0mL of 2-mercaptobenzothiazole solution was added in step (2), and the concentration of 2-mercaptobenzothiazole in the solution system was adjusted to 0.4 mM.

Example 7

In the same manner as in example 1, 3.0mL of 2-mercaptobenzothiazole solution was added only in step (2), and the concentration of 2-mercaptobenzothiazole in the solution system was adjusted to 1.2 mM.

Example 8

In this example, similar to example 1, only 7.0mL of 2-mercaptobenzothiazole solution was added in step (2), and the concentration of 2-mercaptobenzothiazole in the solution system was adjusted to 2.8 mM.

Example 9

In this example, the same procedure as in example 1 was adopted except that 9.0mL of 2-mercaptobenzothiazole solution was added in step (2) and the concentration of 2-mercaptobenzothiazole in the solution system was adjusted to 3.6 mM.

Then, the CuNPs @ PVP/MBT/HYD solutions prepared in example 1 and examples 6 to 9 were detected by a fluorescence spectrometer, and the result is shown in fig. 10, where the synthesized CuNPs @ PVP/MBT/HYD solution had the maximum fluorescence intensity when the final concentration of the 2-mercaptobenzothiazole solution was 2.0mM in an addition volume of 2.0 ml.

Example 10

The technical scheme of the embodiment is the same as that of the embodiment 1, and only 0.2mL of hydrazine hydrate solution is added in the step (2).

Example 11

The technical scheme of the embodiment is the same as that of the embodiment 1, and only 0.6mL of hydrazine hydrate solution is added in the step (2).

Example 12

The technical scheme of the embodiment is the same as that of the embodiment 1, and only 1.0mL of hydrazine hydrate solution is added in the step (2).

Example 13

The technical scheme of the embodiment is the same as that of the embodiment 1, and only 1.5mL of hydrazine hydrate solution is added in the step (2).

The CuNPs @ PVP/MBT/HYD solutions prepared in example 1 and examples 9 to 13 were detected by a fluorescence spectrometer, and the results are shown in fig. 11, where the synthesized CuNPs @ PVP/MBT/HYD solution had the greatest fluorescence intensity when the amount of hydrazine hydrate solution was 0.4 mL.

Example 14

In the same manner as in example 1, the standing time in step (3) was set to 5 min.

Example 15

In the same manner as in example 1, the standing time in step (3) was set to 15 min.

Example 16

In the same manner as in example 1, the standing time in step (3) was set to 20 min.

Example 17

In the same manner as in example 1, the setting of the standing time in step (3) was only 25 min.

Example 18

In the same manner as in example 1, the standing time in step (3) was set to 30 min.

Example 19

In the same manner as in example 1, the standing time in step (3) was set to 40 min.

The CuNPs @ PVP/MBT/HYD solutions prepared in example 1 and examples 14 to 19 were detected by a fluorescence spectrometer, and the results are shown in fig. 12.

Example 20

The present example was conducted in the same manner as example 1 except that the temperature in step (3) was set to 10 ℃.

Example 21

The present example was conducted in the same manner as example 1 except that the temperature in step (3) was set to 20 ℃.

Example 22

The present example was conducted in the same manner as example 1 except that the temperature in step (3) was set to 25 ℃.

Example 23

The present example was conducted in the same manner as example 1 except that the temperature in step (3) was set to 30 ℃.

Example 24

The present example was conducted in the same manner as example 1 except that the temperature in step (3) was set to 40 ℃.

The CuNPs @ PVP/MBT/HYD solutions prepared in example 1 and examples 20 to 24 were detected by a fluorescence spectrometer, and the results are shown in fig. 13. As can be seen from the figure, the fluorescence intensity of the CuNPs @ PVP/MBT/HYD solution prepared at 10 ℃ is strongest, but the preparation process is contrary to the economic and simple concept by controlling the temperature at 10 ℃, so that the optimal reaction temperature is selected to be 15 ℃.

Example 25

The technical scheme of this example is the same as that of example 1, except that the pH of the solution system in step (2) is 1.00.

Example 26

The technical scheme of this example is the same as that of example 1, except that the pH of the solution system in step (2) is 3.00.

Example 27

The technical scheme of this example is the same as that of example 1, except that the pH of the solution system in step (2) is 5.00.

Example 28

The technical scheme of this example is the same as that of example 1, except that the pH of the solution system in step (2) is 7.00.

Example 29

The technical scheme of this example is the same as that of example 1, except that the pH of the solution system in step (2) is 8.00.

Example 30

The technical scheme of this example is the same as that of example 1, except that the pH of the solution system in step (2) is 9.00.

Example 31

The technical scheme of this example is the same as that of example 1, except that the pH of the solution system in step (2) is 10.00.

Example 32

The technical scheme of this example is the same as that of example 1, except that the pH of the solution system in step (2) is 11.00.

Example 33

The technical scheme of this example is the same as that of example 1, except that the pH of the solution system in step (2) is 14.00.

The CuNPs @ PVP/MBT/HYD solutions prepared in example 1 and examples 25 to 33 were detected by a fluorescence spectrometer, and the results are shown in fig. 14. When the pH value of the solution system in the step (2) is 13.45, the fluorescence intensity of the synthesized CuNPs @ PVP/MBT/HYD solution is maximum.

Example 34

The technical scheme of the embodiment is the same as that of the embodiment 1, only the reaction conditions in the step (3) are set to be ultrasonic reaction for 10min, the ultrasonic reaction power is 60W, and the temperature is 15 ℃.

Example 35

The technical scheme of the embodiment is the same as that of the embodiment 1, only the reaction conditions in the step (3) are set as stirring reaction for 10min, the stirring speed is 500rpm/min, and the temperature is 15 ℃.

Example 36

The technical scheme of the embodiment is the same as that of the embodiment 1, only the reaction condition in the step (3) is set as a reaction kettle for reaction for 10min, wherein the reaction temperature in the reaction kettle is 15 ℃.

Example 37

The technical scheme of the embodiment is the same as that of the embodiment 1, only the reaction condition in the step (3) is set as water bath reaction, and the reaction is carried out for 10min at the temperature of 15 ℃ in a water bath kettle.

The CuNPs @ PVP/MBT/HYD solutions prepared in example 1 and examples 34 to 37 were detected by a fluorescence spectrometer, and the results are shown in fig. 15. The fluorescence intensity of the CuNPs @ PVP/MBT/HYD solution synthesized in the embodiment 1 by standing at normal temperature is maximum.

And (3) fluorescence study of interaction of various ions and CuNPs @ PVP/MBT/HYD synthesized in examples 2-37. 0.01M of each ionic solution (Na) was prepared⁺、K⁺、Ni²⁺、Pb²⁺、Ba²⁺、Cd²⁺、Sr²⁺、Mg²⁺、Zn²⁺、Mn²⁺、Ca²⁺、Al³⁺、Fe³⁺、Cu²⁺、Hg²⁺、Ag⁺) 1.0mL of the prepared CuNPs @ PVP/MBT/HYD solution was diluted with 9.0mL of Tris-HCl solution (pH 4.5). Setting parameters of a fluorescence spectrometer (lambda ex is 370nm, lambda em is 500nm-610nm), placing 2.0mL in a fluorescence cuvette to scan a sample, and recording data; and adding 10 mu L of the cation solution into a fluorescent cup, stirring, timing for 2.0min, scanning a sample, and recording data. The results demonstrate that Ag⁺The fluorescence of the CuNPs @ PVP/MBT/HYD solution prepared in the embodiment 2-37 can be quenched, and other cations have almost no influence on the fluorescence of the CuNPs @ PVP/MBT/HYD solution prepared in the embodiment 2-37.

The above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various modifications and improvements of the technical solutions of the present invention can be made by those skilled in the art without departing from the spirit of the present invention, and the technical solutions of the present invention are within the scope of the present invention defined by the claims.

Claims

1. The preparation method of the copper nanoparticle solution is characterized in that the copper nanoparticle solution is prepared by taking copper chloride as a copper precursor, polyvinylpyrrolidone as a protective agent, 2-mercaptobenzothiazole as a stabilizing agent and hydrazine hydrate as a reducing agent and standing at 10-20 ℃.

2. A method for preparing the copper nanoparticle solution according to claim 1, comprising the steps of:

(1) respectively preparing a copper chloride solution, a 2-mercaptobenzothiazole solution and a polyvinylpyrrolidone solution, and sequentially adding the copper chloride solution, the 2-mercaptobenzothiazole solution and the polyvinylpyrrolidone solution into a test tube according to the volume ratio of 1: 1-9: 2-17 to form a mixed solution;

(2) then adding 0.2-1.5 mL of hydrazine hydrate, fixing the volume, and adjusting the pH value of the mixed solution;

(3) and (3) standing the solution obtained in the step (2) at the temperature of 10-20 ℃ for 10-30 minutes, and then dialyzing and purifying the mixed solution by using a dialysis bag with the molecular weight cutoff of 3500 to obtain a colorless copper nanoparticle solution aqueous solution, and storing the colorless copper nanoparticle solution in a refrigerator at the temperature of 4 ℃ in a dark place.

3. The method for preparing a copper nanoparticle solution according to claim 2, wherein the concentration of the copper chloride solution in the step (1) is 1.0mM, the concentration of the polyvinylpyrrolidone solution is 0.07mM, and the concentration of the 2-mercaptobenzothiazole solution is 10.0 mM.

4. The method for preparing a copper nanoparticle solution according to claim 2, wherein the volume ratio of the copper chloride solution, the 2-mercaptobenzothiazole solution and the polyvinylpyrrolidone solution in the step (1) is 1:5: 10.

5. The method for preparing a copper nanoparticle solution according to claim 2, wherein the amount of hydrazine hydrate added in step (2) is 0.4mL, and the pH of the mixed solution is 12.0-14.0.

6. The method for preparing a copper nanoparticle solution according to claim 2, wherein the temperature of the solution in the step (3) is 15 ℃ and the standing time is 10 minutes.

7. A copper nanoparticle solution prepared by the method of any one of claims 1-6.

8. Use of the copper nanoparticle solution of claim 7 for the detection of silver ions.

9. Use of the orange fluorescent copper nanoparticle solution of claim 7 in pattern dyeing manufacture.