阅读说明：本技术 一种苦瓜状CuO纳米颗粒SERS基底制备方法 (Preparation method of bitter gourd-shaped CuO nanoparticle SERS substrate ) 是由 孟琪 黄杰 沈为民 梁培 曹宇 周勇峰 于 2019-01-10 设计创作，主要内容包括：本发明提供了一种苦瓜状CuO纳米颗粒SERS基底制备方法,属于SERS技术领域。通过将氢氧化钠、葡萄糖、醋酸铜、聚乙烯吡咯烷酮溶液混合,并将混合溶液进行水热反应得到苦瓜状CuO纳米颗粒,其中氢氧化钠、葡萄糖、醋酸铜、聚乙烯吡咯烷酮的物质的量之比为2:1:1:1,水热反应的温度为60℃,水热反应时间为5-7小时。将CuO纳米颗粒溶于去离子水中,用滴管将溶液滴到基底上,放入真空干燥箱,干燥温度为50℃,干燥6小时后即可得到苦瓜状CuO纳米颗粒SERS基底。这种方法具有制备工艺简单,成本低,所制备基底均匀性好,表面粗糙度高,灵敏度高,稳定性好等优点。(The invention provides a preparation method of a bitter gourd-shaped CuO nanoparticle SERS substrate, and belongs to the technical field of SERS. The bitter gourd-shaped CuO nano-particles are obtained by mixing sodium hydroxide, glucose, copper acetate and polyvinylpyrrolidone solutions and carrying out hydrothermal reaction on the mixed solution, wherein the mass ratio of the sodium hydroxide to the glucose to the copper acetate to the polyvinylpyrrolidone is 2:1:1:1, the temperature of the hydrothermal reaction is 60 ℃, and the hydrothermal reaction time is 5-7 hours. Dissolving CuO nano particles in deionized water, dripping the solution on a substrate by using a dropper, putting the substrate into a vacuum drying oven, and drying for 6 hours at the drying temperature of 50 ℃ to obtain the bitter gourd-shaped CuO nano particle SERS substrate. The method has the advantages of simple preparation process, low cost, good uniformity of the prepared substrate, high surface roughness, high sensitivity, good stability and the like.)

1. A preparation method of a bitter gourd-shaped CuO nanoparticle SERS substrate comprises the following steps:

step one, preparing sodium hydroxide mother liquor, namely weighing 0.064g of sodium hydroxide solid, putting the sodium hydroxide solid into a volumetric flask, and adding 100m L deionized water to prepare the sodium hydroxide mother liquor with the concentration of 16 mmol/L;

step two, preparing copper acetate mother liquor, namely weighing 0.16g of copper acetate solid, putting the copper acetate solid into a beaker, adding 100m L deionized water, and preparing the copper acetate mother liquor with the concentration of 8 mmol/L;

step three: preparing a mixed solution A: weighing glucose powder, adding the glucose powder into a prepared sodium hydroxide solution, and uniformly stirring the solution by using a glass rod to obtain a mixed solution A;

step four: preparing a mixed solution B: weighing polyvinylpyrrolidone solid powder, adding the polyvinylpyrrolidone solid powder into the prepared copper acetate solution, continuously stirring the solution on a constant-temperature magnetic stirrer at the rotating speed of 600rpm for 10 minutes to obtain a mixed solution B;

step five: pouring the mixed solution A into the mixed solution B at a constant speed, and continuously stirring for 60 minutes;

step six: pouring the mixed solution obtained in the fifth step into a hydrothermal reaction kettle, and immediately putting the hydrothermal reaction kettle into an air-blast drying oven for hydrothermal reaction;

step seven: centrifuging and washing the solution after the hydrothermal reaction is finished, wherein the eccentricity is 10000rpm, the centrifuging time is 20 minutes each time, and centrifuging is carried out for 3 times to obtain bitter gourd-shaped CuO nanoparticles;

step eight: dissolving the bitter gourd-shaped CuO nanoparticles in deionized water, dripping the solution onto a silicon or silicon dioxide substrate by using a dropper, and drying for 6 hours in a vacuum drying oven at the drying temperature of 50 ℃ to finally obtain the bitter gourd-shaped CuO nanoparticle SERS substrate;

the method is characterized in that: the mass ratio of glucose to sodium hydroxide in the mixed solution A is 1: 2; the mass ratio of the copper acetate to the polyvinylpyrrolidone in the mixed solution B is 1: 1.

2. The preparation method of the SERS substrate of bitter gourd-like CuO nanoparticles of claim 1, comprising: the method is characterized in that the temperature of the hydrothermal reaction is 60 ℃.

3. The preparation method of the SERS substrate of bitter gourd-like CuO nanoparticles of claim 1, comprising: it is characterized in that the time of the hydrothermal reaction is 5 to 7 hours.

4. The method for preparing the SERS substrate of bitter gourd-like CuO nanoparticles according to claim 1, wherein the K value of polyvinylpyrrolidone is 17.

Technical Field

The invention relates to a preparation method of an SERS substrate, in particular to a preparation method of an SERS substrate of CuO nanoparticles, and belongs to the technical field of SERS.

Background

The SERS enhancement mechanism mainly lies in electromagnetic Enhancement (EM) caused by surface plasmon resonance (L SPR) and chemical enhancement (CM) caused by electron migration (CT), wherein L SPR dominates the SERS enhancement effect, therefore, the intensity of SERS signals depends greatly on the SERS substrate enhancement effect, currently, precious metals (Au, Ag and Cu) have stronger L SPR and are widely used as SERS substrate materials, the three metals have the property of covering most of visible light and infrared light wavelength ranges, most of Raman measurements are carried out in the SERS substrate enhancement effect, which also enables the SERS substrates to have more excellent SERS effects, for example, Jea P and the like use a gold and silver nanoparticle surface Self-assembly method to prepare the SERS substrate and issue a Self-assembly of the SERS nanoparticles PmpPD/PANOFFIS technology and release the problem that the bioanals technologies such as SERS nanoparticles 573, SERS 5716, Ag-substrate aggregation, Ag-5716, which is very easy to develop in the fields of high sensitivity, fast detection, providing molecular structure information, and the like, but the development of SERS nanoparticles is very easy to the bioanalysis technologies such as SERS substrate 5716, SERS substrate excitation cost is very low, SERS substrate excitation cost is high, SERS substrate excitation cost, SERS substrate is high, SERS-induced by SERS.

The nanometer metal oxide has high electron mobility, simple preparation process, low cost and easily controlled size and shape of nanometer material, and is widely used as photocatalytic material, electron transport layer material of photoelectric luminescent device, battery material and the like. When molecules are attached to the surface of the nano metal oxide, the SERS chemical enhancement effect is easily formed due to the high electron mobility of the nano metal oxide. Among common metal oxides, CuO is widely applied to the fields of catalysis, sensing and the like due to the advantages of no toxicity, low cost, good chemical stability, easily controlled shape and appearance of nano materials and the like. However, compared with noble metals, the SERS enhancement effect is weaker, and in order to further improve the SERS enhancement effect, a surface superstructure such as a needle tip structure, an island structure and the like is effectively constructed, so that the surface local plasma resonance effect is improved, and the SERS sensitivity is further improved. Similar to Chang group, ZnO nanometer needle tip is grown in large area at low temperature, and experiments prove that the ZnO nanometer needle tip has higher photocatalysis and Raman enhancement effects; guo group used Cu alone₂Cubic structure of O nanosphereThe super structure is used for testing the enhancement factor of the SERS substrate formed by the super structure by adopting marker molecules, and the enhancement factor can reach 8 × 10⁵And has high sensitivity. Although in ZnO and Cu₂Metal oxide superstructure SERS substrates such as O have been successfully prepared, but there are few reports relating to CuO nanoparticle SERS substrates based on high surface roughness and surface superstructure.

Disclosure of Invention

In order to prepare the CuO nanoparticles with high surface roughness and construct the high-sensitivity SERS substrate based on the CuO nanoparticles with high surface roughness, the invention aims to provide the preparation method of the bitter gourd-shaped CuO nanoparticle SERS substrate, the preparation process is simple, the cost is low, and the prepared SERS substrate has high sensitivity.

The invention comprises the following steps:

step one, preparing sodium hydroxide mother liquor, namely weighing 0.064g of sodium hydroxide solid, putting the sodium hydroxide solid into a beaker, and adding 100m L deionized water to prepare the sodium hydroxide mother liquor with the concentration of 16 mmol/L;

step two, preparing copper acetate mother liquor, namely weighing 0.16g of copper acetate solid, putting the copper acetate solid into a beaker, adding 100m L deionized water, and preparing the copper acetate mother liquor with the concentration of 8 mmol/L;

step three: preparing a mixed solution A: weighing glucose powder, adding the glucose powder into a prepared sodium hydroxide solution, wherein the mass ratio of glucose to sodium hydroxide is 1:2, and uniformly stirring the solution by using a glass rod to obtain a mixed solution A;

step four: preparing a mixed solution B: weighing polyvinylpyrrolidone solid powder with a K value of 17, adding the polyvinylpyrrolidone solid powder into a prepared copper acetate solution, wherein the mass ratio of copper acetate to polyvinylpyrrolidone is 1:1, continuously stirring the solution on a constant-temperature magnetic stirrer at the rotating speed of 600rpm for 10 minutes to obtain a mixed solution B;

step five: pouring the mixed solution A into the mixed solution B at a constant speed, and continuously stirring for 60 minutes;

step six: pouring the mixed solution obtained in the fifth step into a hydrothermal reaction kettle, immediately putting the hydrothermal reaction kettle into an air-blast drying oven for hydrothermal reaction, wherein the temperature of the hydrothermal reaction is 60 ℃, and the reaction time is 5-7 hours;

step seven: centrifuging and washing the solution obtained after the hydrothermal reaction is finished, wherein the eccentricity is 10000rpm, the centrifuging time is 20 minutes each time, centrifuging is carried out for 3 times, and the bitter gourd-shaped CuO nano particles can be obtained after the centrifuging is finished;

step eight: dissolving CuO nano particles in deionized water, dripping the solution on a substrate by using a dropper, putting the substrate into a vacuum drying oven, and drying for 6 hours at the drying temperature of 50 ℃ to obtain the bitter gourd-shaped CuO nano particle SERS substrate.

The invention has the beneficial effects that:

1. the SERS substrate prepared by the invention has low cost and simple preparation process flow.

2. The SERS substrate prepared by the invention has the advantages of uniform distribution of nano particles, uniform particle size and high surface roughness.

3. The SERS substrate prepared by the invention has high sensitivity, high repeatability and high stability.

Drawings

FIG. 1 is an SEM image of a bitter gourd-like CuO nanoparticle powder on a surface of a SERS substrate in an embodiment of the present invention;

FIG. 2 is a powder XRD pattern of bitter gourd-like CuO nanoparticles on the surface of a SERS substrate in an embodiment of the present invention;

FIG. 3 is an EDS plot of bitter gourd-like CuO nanoparticle powder at the surface of a SERS substrate in an embodiment of the present invention;

fig. 4 is a raman spectrum of a measurement of different concentrations R6G of SERS substrate labels in an embodiment of the invention.

Detailed Description

A preparation method of a bitter gourd-shaped CuO nanoparticle SERS substrate comprises the following steps:

step one, preparing sodium hydroxide mother liquor, namely weighing 0.064g of sodium hydroxide solid, putting the sodium hydroxide solid into a beaker, and adding 100m L deionized water to prepare the sodium hydroxide mother liquor with the concentration of 16 mmol/L;

step two, preparing copper acetate mother liquor, namely weighing 0.16g of copper acetate solid, putting the copper acetate solid into a beaker, adding 100m L deionized water, and preparing the copper acetate mother liquor with the concentration of 8 mmol/L;

step three: preparing a mixed solution A: weighing glucose powder, adding the glucose powder into a prepared sodium hydroxide solution, wherein the mass ratio of glucose to sodium hydroxide is 1:2, and uniformly stirring the solution by using a glass rod to obtain a mixed solution A;

step four: preparing a mixed solution B: weighing polyvinylpyrrolidone solid powder with a K value of 17, adding the polyvinylpyrrolidone solid powder into a prepared copper acetate solution, wherein the mass ratio of copper acetate to polyvinylpyrrolidone is 1:1, continuously stirring the solution in a constant-temperature magnetic stirrer at the rotating speed of 600rpm for 10 minutes to obtain a mixed solution B;

step five: pouring the mixed solution A into the mixed solution B at a constant speed, and continuously stirring for 60 minutes;

step six: pouring the mixed solution obtained in the fifth step into a hydrothermal reaction kettle, immediately putting the hydrothermal reaction kettle into an air-blast drying oven for hydrothermal reaction, wherein the temperature of the hydrothermal reaction is 60 ℃, and the reaction time is 5-7 hours;

step seven: centrifuging and washing the solution obtained after the hydrothermal reaction is finished, wherein the eccentricity is 10000rpm, the centrifuging time is 20 minutes each time, centrifuging is carried out for 3 times, and the bitter gourd-shaped CuO nano particles can be obtained after the centrifuging is finished;

step eight: dissolving CuO nano particles in deionized water, dripping the solution on a substrate by using a dropper, putting the substrate into a vacuum drying oven, and drying for 6 hours at the drying temperature of 50 ℃ to obtain the bitter gourd-shaped CuO nano particle SERS substrate.