Solid surface enhanced Raman scattering substrate and preparation method and application thereof
By directly growing silver nanoflowers on filter paper, the problems of low yield and high cost in SERS substrate preparation were solved, and high-sensitivity, low-cost solid-state Raman substrate preparation was achieved, which is suitable for chemical analysis and detection.
Patent Information
- Application Number
- CN202410491395.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-23
- Publication Date
- 2025-10-24
AI Technical Summary
In the prior art, the preparation methods of SERS substrates have low yield and high cost, making it difficult to achieve efficient and low-cost preparation.
Using the continuous ion layer adsorption and reaction method, silver nanoflowers are directly grown on filter paper through the redox reaction of silver nitrate and ascorbic acid to form a solid surface-enhanced Raman scattering substrate, eliminating the step of depositing the silver nanoflowers on a solid substrate.
A silver nanoflower Raman substrate was prepared that is easy to carry, easy to store, and has a long shelf life. It has high sensitivity and excellent SERS performance, and can meet different detection sensitivity requirements quickly and at low cost.
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Figure CN120831344A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the field of chemical analysis and detection, and particularly relates to a solid-state surface-enhanced Raman scattering substrate and a preparation method and application thereof. BACKGROUND
[0002] Surface-enhanced Raman scattering (SERS) is an abnormal optical enhancement effect based on a nanoscale rough surface or a particle system, can detect single-layer and sub-single-layer molecules adsorbed on a metal surface, has the advantages of rich information content, rapidness, precision, high sensitivity, no need for sample pretreatment and simple operation, and is therefore widely used in many scientific fields such as chemistry, physics, biology and materials.
[0003] The enhancement effect of surface-enhanced Raman scattering (SERS) is greatly related to the composition, shape and surface morphology of the substrate, and the preparation of a SERS enhancement substrate with good performance is a current research hotspot. Gold, silver and copper noble metals are the most commonly used materials for preparing SERS enhancement substrates, and among them, silver is the material with the best enhancement effect, and silver nanoflowers with a three-dimensional structure are an excellent choice for preparing SERS substrates with high Raman spectrum signal sensitivity due to many sharp nanometer edges.
[0004] At present, the mainstream method for preparing a SERS substrate is to first synthesize nanoparticles and then deposit the nanoparticles on a solid substrate, and this process has a low yield and a high preparation cost. Therefore, a method for preparing a SERS substrate with a high yield, a low cost and fast preparation needs to be sought. SUMMARY
[0005] The present application is carried out to solve the above problems, and aims to provide a solid-state surface-enhanced Raman scattering substrate, a preparation method and a SERS detection method.
[0006] To achieve the above-mentioned purpose, the present application provides a solid-state surface-enhanced Raman scattering substrate, which has the following characteristics and comprises:
[0007] The solid support is filter paper, and the metal nanoparticles are silver nanoflowers.
[0008] Preferably, the filter paper is any one of qualitative filter paper or quantitative filter paper.
[0009] The present application further provides a preparation method of a solid-state surface-enhanced Raman scattering substrate, which has the following characteristics and comprises the following steps:
[0010] S1, preparing a silver nitrate solution and an ascorbic acid solution;
[0011] S2, preparing a dispersant, cutting filter paper, and using a continuous ion layer adsorption and reaction method to allow the silver nitrate solution, the ascorbic acid solution, and the dispersant to form silver nanoflowers on the filter paper to prepare a deposition sample filter paper;
[0012] S3, waiting for the deposited sample filter paper to dry to obtain the silver nanoflower Raman substrate.
[0013] Preferably, the concentration ratio of the silver nitrate solution to the ascorbic acid solution is 0.5-2.
[0014] Preferably, the dispersant is any one of ultrapure water or deionized water.
[0015] Preferably, the reaction temperature of S2 is controlled at 15-25°C.
[0016] The present invention also provides application of the solid-state surface-enhanced Raman scattering substrate in detecting Rhodamine 6G.
[0017] The present invention also provides a solid-state surface-enhanced Raman scattering detection method using the above-mentioned silver nanoflower Raman substrate, which has the following characteristics and comprises the following steps:
[0018] Step 1: drop the Rhodamine 6G solution to be tested onto the surface of the silver nanoflower Raman substrate to obtain a Raman spectrum;
[0019] Step 2: Select 611cm from the Raman spectrum. -1 、772cm -1 、1181cm -1 、1310cm -1 、1362cm -1 、1509cm -1 、1574cm -1 and 1649cm -1 The peak intensity of the characteristic peak at was used for quantification.
[0020] Compared with the prior art, the present invention has the following beneficial effects:
[0021] 1. The silver nanoflower Raman substrate of the present invention is in solid form, easy to carry, easy to store and has a long shelf life.
[0022] 2. The silver nanoflower Raman substrate of the present invention can obtain SERS substrates with different morphologies by adjusting the concentrations of silver nitrate and ascorbic acid solution, which can meet different detection sensitivity requirements.
[0023] 3. The silver nanoflower Raman substrate of the present invention has high sensitivity, such as the detection limit of rhodamine 6G is 10 -11 M.
[0024] 4、The silver nanoflower Raman substrate preparation method provided by the application uses the simple and low-cost continuous ion layer adsorption and reaction method, through the redox reaction of silver nitrate and ascorbic acid, silver nanoflowers with high Raman spectrum signal sensitivity are directly grown on filter paper without adding complexing agents. Compared with other methods, the silver nanoflowers can be directly grown on the filter paper, the preparation is very rapid and fast, has excellent SERS performance, and at the same time, the step of depositing the silver nanoflowers on the solid substrate in the traditional preparation is omitted, which can greatly promote production. BRIEF DESCRIPTION OF DRAWINGS
[0025] Figure 1 is a scanning electron microscope graph of the silver nanoflower Raman substrate in Example 1 of the application;
[0026] Figure 2 is a preparation flowchart of the silver nanoflower Raman substrate in Example 2 of the application;
[0027] Figure 3 is an energy dispersive X-ray spectrum graph of the silver nanoflower Raman substrate in Example 2 of the application;
[0028] Figure 4 is an X-ray diffraction spectrum graph of the silver nanoflower Raman substrate in Example 2 of the application;
[0029] Figure 5 is an ultraviolet-visible extinction spectrum graph of the silver nanoflower Raman substrate in Example 2 of the application;
[0030] Figure 6 is a SERS spectrum graph of the silver nanoflower Raman substrate in Example 3 of the application for different concentrations of rhodamine 6G;
[0031] Figure 7 is a SERS response graph of the quantitative analysis method of the silver nanoflower Raman substrate in Example 3 of the application for quantitative analysis of rhodamine 6G molecules. DETAILED DESCRIPTION
[0032] The technical solutions in the embodiments of the application will be described clearly and completely below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the application.
[0033] Example 1:
[0034] Figure 1 is a scanning electron microscope graph of the silver nanoflower Raman substrate in Example 1 of the application.
[0035] AsFigure 1 As shown in the embodiment 1, the solid-state surface-enhanced Raman scattering substrate comprises a solid support and metal nanoparticles distributed on the surface and inside of the solid support, wherein the solid support is filter paper, and the metal nanoparticles are silver nanoflowers.
[0036] In the embodiment, the filter paper is any one of qualitative filter paper or quantitative filter paper.
[0037] Embodiment 2
[0038] The embodiment 2 uses a simple and low-cost continuous ion layer adsorption and reaction method to grow silver nanoflowers with high Raman spectrum signal sensitivity on filter paper through the redox reaction of silver nitrate and ascorbic acid without adding a complexing agent. The synthesized silver nanoflower Raman substrate has excellent SERS performance, and at the same time, the step of depositing silver nanoflowers on a solid substrate is omitted, which can greatly promote production.
[0039] Figure 2 The figure is a preparation flowchart of the silver nanoflower Raman substrate in the embodiment 2 of the present application.
[0040] As shown in the embodiment 2, the present application provides a preparation method of a solid-state surface-enhanced Raman scattering substrate, comprising the following steps: Figure 2
[0041] S1, preparing a silver nitrate solution and an ascorbic acid solution.
[0042] The concentration ratio of the silver nitrate solution and the ascorbic acid solution is 0.5-2. By adjusting the concentration ratio between the silver source solution and the reducing agent, the morphology of the solid-state surface-enhanced Raman scattering substrate can be changed, and the detection sensitivity of the solid-state surface-enhanced Raman scattering substrate can be improved.
[0043] Specifically, 10 milliliters of 0.1M silver nitrate (AgNO3) solution is taken as a silver source and placed in a beaker. Then, another beaker is taken, and 10 milliliters of 0.1M ascorbic acid (AA) solution is poured into the beaker as a reducing agent. The silver source is any one of silver nitrate, and the reducing agent is any one of ascorbic acid.
[0044] S2, preparing a dispersant, cutting filter paper, and generating silver nanoflowers on the filter paper through the continuous ion layer adsorption and reaction method, so as to prepare a deposition sample filter paper.
[0045] The dispersant is any one of ultrapure water or deionized water.
[0046] In this embodiment, two beakers were taken, and 10 milliliters of deionized water was respectively poured into each beaker, and a piece of 3x1 centimeter filter paper was cut for standby. The synthesis of a typical solid-state surface-enhanced Raman scattering substrate was carried out by fifteen times of continuous ion layer adsorption and reaction method at a reaction temperature; specifically, in a standard cycle, the filter paper was dipped in a beaker containing silver nitrate (AgNO3) solution, deionized water, ascorbic acid (AA) solution and deionized water in turn by using a pair of tweezers, and the filter paper was soaked in each beaker for 30 seconds, and finally the silver nanoflower with high Raman spectrum signal sensitivity was grown on the filter paper to prepare a deposited sample filter paper.
[0047] The reaction temperature of step S2 was controlled at 15-25℃, and the preferred reaction temperature was 15℃.
[0048] S3, after the deposited sample filter paper was naturally dried in a light-proof environment atmosphere, a silver nanoflower Raman substrate was prepared.
[0049] The prepared silver nanoflower Raman substrate was subjected to scanning electron microscope test, and the result was as shown in Figure 1 The sample was uniformly and densely distributed on the fibers of the filter paper, the overall morphology of the sample presented a spherical shape, and the surface had a secondary nanocrystalline structure, which presented a morphology similar to the nanoflower, and had a large number of hot spots.
[0050] Figure 3 is the energy dispersive X-ray spectrum of the silver nanoflower Raman substrate in Example 2 of the present application.
[0051] The prepared silver nanoflower Raman substrate was subjected to energy dispersive X-ray test, and the result was as shown in Figure 3 The silver nanoflower was mainly composed of silver and a small amount of impurities. An obvious carbon peak was observed near 0 keV, which may be derived from the organic impurities introduced by the conductive glue used for fixing the sample or the external pollutants in contact with the surface of the sample.
[0052] Figure 4 is the X-ray diffraction spectrum of the silver nanoflower Raman substrate in Example 2 of the present application.
[0053] The prepared silver nanoflower Raman substrate was subjected to X-ray color test, and the result was as shown in Figure 4 The diffraction peaks observed at 38.0°, 44.2°, 64.3°, 77.2° and 81.3° corresponded to the (111), (200), (220), (311) and (222) crystal planes of face-centered cubic (fcc) Ag, respectively.
[0054] Figure 5 is the ultraviolet-visible extinction spectrum of the silver nanoflower Raman substrate in Example 2 of the present application.
[0055] The silver nanoflower Raman substrate prepared was subjected to UV-visible test, and the results are shown in Figure 5 FIG. 1. A sharp peak appeared at 311 nm, and a wide peak appeared at 392 nm. The characteristic peak at 392 nm is the absorption peak of the flaky grains on the periphery of the silver nanoflower, because the thickness and lateral size of the flaky structure have a significant difference, resulting in a large half-peak width. The sharp and high-intensity absorption peak at 311 nm is the characteristic peak of the silver nanoflower.
[0056] The application also provides the use of the solid-state surface-enhanced Raman scattering substrate of the above-mentioned embodiments 1 and 2 in detecting rhodamine 6G.
[0057] Embodiment 3:
[0058] In this embodiment 3, the silver nanoflower Raman substrate prepared in the above-mentioned embodiment 2 was used to detect rhodamine 6G by solid-state surface-enhanced Raman scattering (SERS), and the detection method comprises the following steps:
[0059] S1, the rhodamine 6G solution to be detected was added dropwise to the surface of the silver nanoflower Raman substrate to obtain a Raman spectrum.
[0060] In this embodiment 3, 1 μL of each rhodamine 6G solution with different concentrations was added dropwise to the surface of the silver nanoflower Raman substrate prepared in the above-mentioned embodiment 2, and then SERS detection was performed by using inVia Qontor Raman instrument, the excitation intensity was set to 50 mV, the integration time was set to 1 s, 10 times of continuous testing were performed for each concentration, and the average value of the 10 data was used for statistics.
[0061] Figure 6 FIG. 3 is the SERS spectrum of the silver nanoflower Raman substrate in embodiment 3 for different concentrations of rhodamine 6G. FIG. b) is a partial enlarged view of FIG. a).
[0062] As shown in Figure 6 , when the silver nanoflower Raman substrate was used for SERS detection of rhodamine 6G solutions with different concentrations, the SERS signal still existed when the concentration of the rhodamine 6G solution was 10 -11 M, indicating that the silver nanoflower Raman substrate can produce strong SERS effect and has high sensitivity.
[0063] S2, from the Raman spectrum, 611 cm -1 , 772 cm -1 , 1181 cm -1 , 1310 cm -1 , 1362 cm -1 , 1509 cm -1 , 1574 cm -1 and 1649 cm -1The peak intensity at the characteristic peak is used for quantification.
[0064] Figure 7 SERS response graph for the quantitative analysis of Rhodamine 6G molecules by the quantitative analysis method of the silver nanoflower Raman substrate in Example 3 of the present application.
[0065] Figure 7 The relationship graph between the SERS intensity of the Raman characteristic peaks at 611 cm -1 , 772 cm -1 , 1181 cm -1 and 1362 cm -1 of the silver nanoflower Raman substrate and the logarithm of the concentration of Rhodamine 6G was plotted, and the logarithm of the concentration of Rhodamine 6G was linearly regressed with the SERS intensity of the above four Raman characteristic peaks, and the fitting coefficient (R2) was taken as the measurement standard of the linearity.
[0066] As shown in Figure 7 , the R2 at 772 cm -1 reached 0.89707, and the R2 values at the other three characteristic peaks also exceeded 0.8, showing good correlation. This shows that with the increase of the concentration of Rhodamine 6G molecules, the intensity of the Raman scattering signal almost increases in direct proportion.
[0067] Although the above has shown and described the embodiments of the present application, it can be understood by those skilled in the art that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and spirits of the present application, and the scope of the present application is defined by the appended embodiments and their equivalents.
Claims
1. A solid state surface enhanced Raman scattering substrate, characterized in that, Comprise: a solid support and metal nanoparticles distributed on the surface and inside of the solid support, the solid support is filter paper, and the metal nanoparticles are silver nanoflowers.
2. The solid-state surface-enhanced Raman scattering substrate of claim 1, wherein: The filter paper is any one of qualitative filter paper or quantitative filter paper.
3. A method of making a solid surface enhanced Raman scattering substrate, characterized by, Comprise the following steps: S1, preparing silver nitrate solution and ascorbic acid solution; S2, preparing dispersant, cutting filter paper, and making silver nanoflowers on the filter paper by continuous ion layer adsorption and reaction method to obtain deposited sample filter paper; S3, drying the deposited sample filter paper to obtain silver nanoflower Raman substrate.
4. The method of making a solid surface-enhanced Raman scattering substrate of claim 3, wherein: The concentration ratio of the silver nitrate solution and the ascorbic acid solution is 0.5-2.
5. The method of making a solid surface- enhanced Raman scattering substrate of claim 3, wherein: The dispersant is any one of ultrapure water or deionized water.
6. The method of making a solid surface-enhanced Raman scattering substrate of claim 3, wherein: The reaction temperature of S2 is controlled at 15-25℃.
7. Application of the solid-state surface-enhanced Raman scattering substrate in any one of claims 1-6 in detecting rhodamine 6G.
8. A solid surface enhanced Raman scattering detection method using the silver nanoflower Raman substrate according to any one of claims 3-6, characterized in that, Comprise the following steps: Step one, adding the rhodamine 6G solution to be detected to the surface of the silver nanoflower Raman substrate to obtain Raman spectrum; Step two, the peak intensity of the characteristic peaks at 611 cm -1 , 772 cm -1 , 1181 cm -1 , 1310 cm -1 , 1362 cm -1 , 1509 cm -1 , 1574 cm -1 and 1649 cm -1 was selected from the Raman spectrum for quantification.