CN112921276A - Preparation method of SERS substrate based on 2D noble metal nanostructure - Google Patents
Preparation method of SERS substrate based on 2D noble metal nanostructure Download PDFInfo
- Publication number
- CN112921276A CN112921276A CN202110087194.3A CN202110087194A CN112921276A CN 112921276 A CN112921276 A CN 112921276A CN 202110087194 A CN202110087194 A CN 202110087194A CN 112921276 A CN112921276 A CN 112921276A
- Authority
- CN
- China
- Prior art keywords
- substrate
- noble metal
- polymer microsphere
- sers
- sers substrate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
- C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
- C23C14/24—Vacuum evaporation
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
- C23C14/04—Coating on selected surface areas, e.g. using masks
- C23C14/042—Coating on selected surface areas, e.g. using masks using masks
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
- C23C14/06—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the coating material
- C23C14/14—Metallic material, boron or silicon
- C23C14/18—Metallic material, boron or silicon on other inorganic substrates
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
- C23C14/06—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the coating material
- C23C14/14—Metallic material, boron or silicon
- C23C14/20—Metallic material, boron or silicon on organic substrates
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
- C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
- C23C14/24—Vacuum evaporation
- C23C14/28—Vacuum evaporation by wave energy or particle radiation
- C23C14/30—Vacuum evaporation by wave energy or particle radiation by electron bombardment
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
- G01N21/65—Raman scattering
- G01N21/658—Raman scattering enhancement Raman, e.g. surface plasmons
Abstract
The invention provides a preparation method of an SERS substrate based on a 2D noble metal nano structure, belonging to the technical field of nano processing. The method specifically comprises the following steps: the method comprises the steps of self-assembling a layer of polymer microsphere array on the surface of a substrate, etching by oxygen plasma to change the polymer microsphere array with a smooth surface into a plush polymer microsphere array, depositing noble metal on the surface of the polymer microsphere array by taking the structure as a template, and etching the template to obtain the SERS substrate. The surface of the SERS substrate is paved with a noble metal layer with needle-shaped protruding structures, gaps among the needle-shaped protruding structures are smaller than 20nm, the nano structures are arranged compactly, distributed uniformly and have good periodicity, a continuous and uniform enhanced electromagnetic field is obtained, the detection sensitivity of the SERS device is obviously improved, and the SERS substrate has excellent repeatability and stability. In addition, the preparation method provided by the invention can realize high-efficiency processing and large-scale production, and reduce the production cost.
Description
Technical Field
The invention belongs to the technical field of nano processing, and particularly relates to a preparation method of an SERS substrate based on a 2D noble metal nano structure.
Background
Surface Enhanced Raman Scattering (SERS) is one of the most impressive applications of plasma physics and is crucial for understanding various fundamental interface processes and interaction mechanisms. SERS enhances local Electromagnetic (EM) energy to 6 orders of magnitude or even higher through diverse metal nanogaps (so-called hot spots), greatly enhances intermolecular and intermolecular-to-metal interactions, thus enabling single molecule detection and identification, and gathering abundant vibrational information with sub-nanometer accuracy. Common SERS substrates include gold nanoparticle (AuNPs) arrays, silver nanoparticle (AgNPs) arrays and the like, although gaps below 10 nanometers can be easily prepared on the substrates to serve as enhancement units, the repeatability and stability of SERS signals are poor, and the application of ultra-sensitive SERS is seriously hindered. Furthermore, the size and volume of such conventional enhancement units (zero-dimensional hot spots) are too small to be practical.
In order to avoid the problems of poor repeatability and stability inherent in the conventional SERS substrate, many novel artificial SERS substrates have been successfully prepared, and various nano-fabrication techniques such as Electron Beam Lithography (EBL), Focused Ion Beam (FIB) lithography, dip pen lithography (DPN), Laser Interference Lithography (LIL), nanoimprint lithography, Anodic Aluminum Oxide (AAO) template-based fabrication techniques, and the like have been used to obtain nanogaps. However, most of these methods require expensive equipment and complicated processes, and can process even very small area of sample, which greatly limits the practicality and adaptability of SERS substrates.
The colloid self-assembly technology is a flexible, cheap and high-throughput large-scale nano processing technology, but the performance of the SERS substrate prepared based on the technology is still unsatisfactory. This is mainly because most of the region of the SERS substrate is occupied by the colloidal particles, and these submicron-sized colloidal particles cannot form an effective electromagnetic enhancement field, and cannot realize raman signal enhancement of the adsorbed target molecule, and only the gaps (usually sub-100 nm) between the colloidal particles can form extremely strong hot spots. For extremely low concentrations of target molecules, it is difficult to distribute uniformly over these sparse and unevenly distributed hot spots, and actual SERS detection requires point-to-point and batch-to-batch repeatability. And it is difficult to prepare plasma nanostructure array with sub-20 nanometer gap on the surface of colloid particle by colloid self-assembly technology. Therefore, there is an urgent need to develop an SERS substrate with a continuous strong electromagnetic field coverage, ordered and sub-20 nm gap enhancement unit, which can realize repeatable and ultrasensitive molecular detection.
Disclosure of Invention
Aiming at the problems, the invention provides a preparation method of a SERS substrate based on a 2D noble metal nano structure, wherein a noble metal layer with needle-shaped convex structures is paved on the surface of the SERS substrate, the gap between the needle-shaped convex structures is less than 20nm, the nano structures are arranged compactly, distributed uniformly and have good periodicity, and continuous and uniform enhanced electromagnetic fields can be obtained in ultraviolet and visible light wave bands.
A preparation method of a SERS substrate based on a 2D noble metal nano structure is characterized by comprising the following steps:
s1, cleaning and hydrophilizing the substrate;
s2, forming a layer of polymer microsphere array on the surface of the substrate by using a colloid self-assembly method;
s3, performing oxygen plasma etching on the polymer microsphere array for 15-30 min to change the polymer microsphere array with smooth surface into a plush polymer microsphere array; wherein the plush clearance is not more than 30nm, the etching gas is pure oxygen, the flow rate is 20-40 sccm, and the power is 20-50W;
s4, depositing a layer of noble metal on the surface of the plush polymer microsphere array;
s5, removing the plush polymer microsphere array between the precious metal layer and the substrate by adopting a wet etching process to obtain the SERS substrate based on the 2D precious metal nanostructure.
The preparation method of the SERS substrate based on the 2D noble metal nanostructure comprises the following specific steps:
s1, placing the substrate in acetone, absolute ethyl alcohol and deionized water in sequence, ultrasonically cleaning for 5-10 min, taking out, drying by using nitrogen, and carrying out hydrophilic treatment to enable the surface of the substrate to have super-hydrophilic characteristics;
s2, self-assembling a layer of regularly and orderly arranged polymer microsphere arrays on the surface of the substrate obtained by the step S1 by using a colloid self-assembly method, drying at 60 ℃ for 60-90 min, and then performing heat treatment at 80 ℃ for 5-10 min to obtain a substrate A;
s3, performing oxygen plasma etching on the surface of the substrate A obtained in the step S2 for 15-30 min by using a plasma etching machine, so that the smooth polymer microsphere array on the surface of the substrate A is changed into a plush polymer microsphere array, and a substrate B is obtained; wherein the size of the plush gaps is not more than 30nm, the etching gas is pure oxygen, the flow rate is 20-40 sccm, and the power is 20-50W;
s4, depositing a layer of noble metal on the surface of the substrate B obtained in the step S3 by electron beam evaporation or thermal evaporation deposition, wherein the thickness of the noble metal is 15-30 nm, and obtaining a substrate C;
and S5, immersing the substrate C obtained in the step S4 in an acetone or chloroform solution for etching for 30-60 min to remove the plush polymer microsphere array between the precious metal layer and the substrate, so that the precious metal layer covered on the surface of the polymer microsphere is paved on the surface of the substrate, then immersing the substrate C in absolute ethyl alcohol and deionized water for cleaning for 10min respectively to remove the residual organic solution on the surface, and finally drying the substrate C by using nitrogen to obtain the SERS substrate based on the 2D precious metal nanostructure.
Further, the substrate in step S1 is SiO2/Si, glass, quartz, GaAs, GaN, Si3N4And inorganic materials such as SiC, and organic materials such as PDMS (polydimethylsiloxane), PMMA (polymethyl methacrylate), and PI (polyimide).
Further, the hydrophilic treatment step in step S1 is carried out by ultraviolet ozone oxidation, oxygen plasma treatment, or H at 80 ℃2O/H2O2/NH4Soaking in the OH mixed solution.
Further, the material of the polymer microsphere in step S2 is Polystyrene (PS) or PMMA.
Further, the diameter of the polymer microsphere in the step S2 is 0.5-3 μm.
Further, the etching gas in step S3 is a mixed gas (Ar/O) of oxygen and argon2) Alternatively, the flow rate of oxygen is 30-60 sccm, the flow rate of argon is 10-30 sccm, and the power is 20-50W.
Further, the noble metal in step S4 is gold or silver.
The invention has the beneficial effects that:
1. the invention provides a preparation method of a SERS substrate based on a 2D noble metal nanostructure, which comprises the steps of etching a polymer microsphere array with a smooth surface into a plush polymer microsphere array by a plasma etching process, depositing a layer of noble metal on the surface of the polymer microsphere array by taking the structure as a template, etching the template to obtain the SERS substrate, paving a noble metal layer with needle-shaped convex structures on the surface of the SERS substrate, wherein the gaps among the needle-shaped convex structures are less than 20nm, and the nano structures are densely arranged, uniformly distributed and good in periodicity, so that a continuous and uniform enhanced electromagnetic field can be obtained, the detection sensitivity of an SERS device is remarkably improved, and the SERS substrate has excellent repeatability and stability. In addition, the SERS substrate has the light absorption efficiency of 80% at ultraviolet and visible light wave bands, so that a local electromagnetic field is provided, the metal surface, the gap and an analyte are excited to generate strong resonance, and stronger and richer Raman signals are obtained.
2. The method realizes the plush nanostructure process on the surface of the polymer microsphere by combining the colloid self-assembly technology and the plasma etching technology, realizes the batch and high-efficiency processing of the wafer level, is easy to integrate into the existing silicon-based processing technology to realize large-scale production, has simple and flexible process, and is easy to reduce the production cost.
Drawings
Fig. 1 is a micro-topography of a PS microsphere array on a substrate surface obtained in example 1 of the present invention after oxygen plasma etching for different time periods, wherein: (a) and (f) the micro-morphologies of the silicon wafer after 5, 10, 15, 20, 25 and 30min of oxygen plasma etching respectively.
FIG. 2 is a micro-topography of a gold film with different thickness deposited on the surface of a substrate B obtained in example 1 of the present invention, wherein: (a) (f) microscopic morphology of PS microspheres for deposition of gold films 15, 25, 30, 40, 50 and 60nm thick, respectively.
Fig. 3 is a graph of the light reflectivity of the SERS substrate deposited with gold thin films of different thicknesses obtained in example 1 of the present invention.
Fig. 4 is a micro-topography of an SERS substrate in which a gold thin film is spread on the surface of the substrate after PS microspheres are removed from the substrate C on which gold thin films with different thicknesses are deposited, obtained in example 1 of the present invention, wherein: (a) and (C) respectively representing the SERS substrate micro-topography after removing PS microspheres from the substrate C deposited with gold films with the thicknesses of 15 nm, 25nm and 30 nm.
Fig. 5 is a SERS performance characterization result of the SERS substrate obtained in example 2 of the present invention, where: (a) the Raman signal intensity of the SERS substrate surface is plotted along with the molar concentration of R6G molecules; (b) is SERS substrate at 10-9M R6 Raman signal diagrams of 20 random points on the surface after being soaked in ethanol solution of 6G and dried; (c) the Raman signal intensity of the surface of the SERS substrate is plotted along with the change of the molar concentration of the 4-MBA molecules; (d) is SERS substrate at 10-8After soaking and drying in the M4-MBA ethanol solution, a Raman signal graph of 20 random points on the surface is obtained.
Detailed Description
The invention will be further illustrated with reference to specific examples:
example 1
The embodiment provides a method for processing a SERS substrate based on a 2D noble metal nano structure, which specifically comprises the following steps:
s1, depositing the single crystal with 300nm silicon oxide on the surfaceCrystalline silicon (SiO for short)2/Si) substrate is sequentially placed in acetone, absolute ethyl alcohol and deionized water for ultrasonic cleaning for 10min, taken out and dried by nitrogen, and then treated by an ultraviolet ozone system for 30min to enable the surface of the substrate to present super-hydrophilic characteristic;
s2, self-assembling a layer of Polystyrene (PS) microsphere arrays which are regularly and orderly arranged on the surface of the substrate after the treatment in the step S1 by using a colloid self-assembly method, then placing the substrate in a drying oven at 60 ℃ for drying treatment for 90min, and further raising the temperature to 80 ℃ for heat treatment for 5min to obtain a substrate A;
the step S2 of self-assembling a PS microsphere array on the surface of the substrate after the step S1 by using a colloid self-assembly method includes the following specific steps:
and (5) attaching the substrate subjected to the super-hydrophilic treatment in the step (S1) to the surface of the geometric center position of the glass slide so as to achieve the purpose of fixing the substrate. The slide with the substrate mounted thereon was placed in a glass container with an inclination and then deionized water was slowly added until the liquid level just fell below the lower edge of the substrate. A monodisperse solution of high concentration Polystyrene (PS) colloidal particles was diluted to 1% with a polar solvent dissolved with a small amount of KOH and sonicated for 3 min. The diluted PS colloidal particle dispersion slowly diffused along the glass container sidewall to the water-air interface via the injection system to gradually and spontaneously aggregate into a two-dimensional monolayer of colloidal crystals. When the colloid monolayer contacts the lower edge of the substrate, the monolayer colloid can be rapidly self-assembled on the surface of the substrate again under the extremely strong capillary force of a water film on the surface of the substrate, so that a large-area monolayer colloid crystal covering the whole substrate is formed. When the PS colloidal particles completely covered the entire substrate, the injection of the PS colloidal particle dispersion was stopped. Standing for 30min, and slowly pumping out the water solution in the glass container to obtain a layer of regularly and orderly arranged Polystyrene (PS) microsphere array on the surface of the substrate.
S3, performing oxygen plasma etching on the substrate A prepared in the step S2 for 20min by using a plasma etching machine to obtain a substrate B; wherein the etching gas is pure oxygen, the flow rate is 30sccm, and the power is 30 w;
s4, depositing a layer of gold film on the surface of the substrate B obtained in the step S3 by using high vacuum thermal evaporation film deposition equipment, wherein the thickness of the gold film is 25nm, and obtaining a substrate C;
s5, immersing the substrate C obtained in the step S4 in an acetone solution for etching for 50min to remove the plush PS microsphere array between the gold film and the substrate, so that the gold film covered on the surface of the PS microspheres is paved on the surface of the substrate, then immersing the substrate C in absolute ethyl alcohol and deionized water for treatment for 10min respectively to remove the residual organic solution on the surface, and finally drying the substrate C by using nitrogen to obtain the SERS substrate based on the 2D noble metal nano structure.
For the oxygen plasma etching time in step S3, the present embodiment etches 5, 10, 15, 20, 25, and 30min respectively, and the shapes are shown in fig. 1(a) - (f), which indicates that the plasma etching technique can not only process fine plush-like nanostructures on the PS microsphere surface, but also precisely adjust the shapes and distribution of the nanostructures by controlling the etching time, and when the etching time is 15-30 min, the smooth PS microspheres on the substrate a surface become plush-like PS microspheres.
For the thickness of the gold thin film deposited in step S4, the gold thin films with thickness of 15, 25, 30, 40, 50 and 60nm were deposited in the present example, and the morphologies are shown in fig. 2(a) - (f), which shows that the gold thin film not only well preserves the plush-like nanostructures on the surface of PS microspheres, but also uniformly fills the gold nanoparticles into the gaps of the nanostructure array by high vacuum thermal evaporation deposition. However, when the thickness of the gold thin film exceeds 30nm, the nanogap is gradually and completely filled with the gold nanoparticles to form a continuous thin film, which is not favorable for obtaining a continuous enhanced electromagnetic field. The light reflectivity data of the SERS substrates of gold films with different thicknesses are also tested, as shown in FIG. 3, the reflectivity of the SERS substrates is less than 20% (mostly within the range of 5-15%) in the ultraviolet and visible light ranges. That is, the SERS substrate absorbs more than 80% of incident light under the combined action of the plasma effect and the structural scattering effect.
The micro-topography characterization of the SERS substrate after the PS microspheres are removed from the substrate C on which the gold thin films with the thicknesses of 15 nm, 25nm and 30nm are deposited, as shown in fig. 4(a) to (C), shows that the gold thin film on the surface of the SERS substrate has needle-shaped protrusion structures with good periodicity, uniform distribution and dense arrangement, and the gap size between the needle-shaped protrusion structures can be adjusted by controlling the thickness of the gold thin film.
Example 2
The embodiment provides a method for processing a SERS substrate based on a 2D noble metal nano structure, which specifically comprises the following steps:
s1, mixing 2 pieces of SiO2The method comprises the following steps of putting a/Si substrate in acetone, absolute ethyl alcohol and deionized water in sequence, ultrasonically cleaning for 8min, taking out, drying by using nitrogen, and treating for 25min by using an ultraviolet ozone system to enable the surface of the substrate to show super-hydrophilic characteristics;
s2, self-assembling a layer of Polystyrene (PS) microsphere arrays which are regularly and orderly arranged on the surface of the substrate after the treatment in the step S1 by using a colloid self-assembly method, then placing the substrate in a drying box at 60 ℃ for drying treatment for 60min, and further raising the temperature to 80 ℃ for heat treatment for 5min to obtain a substrate A;
s3, performing oxygen plasma etching on the substrate A prepared in the step S2 for 20min by using a plasma etching machine to change the smooth PS microspheres on the surface of the substrate A into plush-shaped PS microspheres to obtain a substrate B; wherein the etching gas is pure oxygen, the flow rate is 30sccm, and the power is 30 w;
s4, depositing a gold film with the thickness of 25nm on the surface of the substrate B prepared in the step S3 by utilizing high vacuum thermal evaporation film deposition equipment;
s5, immersing the sample prepared in the step S4 in an acetone solution for etching for 60min to remove the plush PS microsphere array between the gold film and the substrate, so that the gold film covered on the surface of the PS microspheres is spread on the surface of the substrate, then immersing the substrate in absolute ethyl alcohol and deionized water for treatment for 10min respectively to remove the residual organic solution on the surface, and finally drying the substrate by blowing with nitrogen to obtain the SERS substrate based on the 2D noble metal nano structure.
And (3) performance characterization: the 2 SERS substrates prepared in this example were each cut into 8 pieces, immersed in ethanol solutions of rhodamine 6G (R6G) and 4-MBA molecules of different molar concentrations, and tested for SERS performance by a Raman spectrometer with an excitation light source wavelength of 633nm and a laser power of 0.2 mW.
Fig. 5(a) is a graph of Raman signal intensity of the SERS substrate surface of the present embodiment as a function of molar concentration of R6G molecules;
FIG. 5(b) shows the SERS substrate of this embodiment at 10-9M R6, after being soaked in ethanol solution of 6G and dried, the Raman signal graph of 20 random points on the surface is obtained.
FIG. 5(c) is a graph showing the intensity of Raman signal of the SERS substrate surface according to the embodiment as a function of the molar concentration of 4-MBA molecules;
FIG. 5(d) shows the SERS substrate of this embodiment at 10-8After soaking and drying in the M4-MBA ethanol solution, a Raman signal graph of 20 random points on the surface is obtained.
The result shows that the SERS substrate prepared by the method can detect the concentration as low as 10-11M R6G molecule, even in 4-MBA ethanol solution can reach 10-10M has a detection limit, has excellent detection sensitivity, and exhibits excellent stability and reproducibility at an extremely low concentration.
It will be appreciated by those of ordinary skill in the art that the embodiments described herein are intended to assist the reader in understanding the principles of the invention and are to be construed as being without limitation to such specifically recited embodiments and examples. Those skilled in the art can make various other specific changes and combinations based on the teachings of the present invention without departing from the spirit of the invention, and these changes and combinations are within the scope of the invention.
Claims (8)
1. A preparation method of a SERS substrate based on a 2D noble metal nano structure is characterized by comprising the following steps:
s1, cleaning and hydrophilizing the substrate;
s2, forming a polymer microsphere array on the surface of the substrate by using a colloid self-assembly method;
s3, performing oxygen plasma etching on the polymer microsphere array for 15-30 min to change the polymer microsphere array with smooth surface into a plush polymer microsphere array; wherein the plush clearance is not more than 30nm, the etching gas is pure oxygen, the flow rate is 20-40 sccm, and the power is 20-50W;
s4, depositing a layer of noble metal on the surface of the plush polymer microsphere array;
s5, removing the plush polymer microsphere array between the precious metal layer and the substrate to obtain the SERS substrate based on the 2D precious metal nanostructure.
2. The preparation method of the 2D noble metal nanostructure-based SERS substrate according to claim 1, comprising the following steps:
s1, placing the substrate in acetone, absolute ethyl alcohol and deionized water in sequence, ultrasonically cleaning, taking out, drying by using nitrogen, and carrying out hydrophilic treatment to enable the surface of the substrate to have super-hydrophilic characteristics;
s2, self-assembling a layer of regularly and orderly arranged polymer microsphere arrays on the surface of the substrate obtained by the step S1 by using a colloid self-assembly method, drying at 60 ℃ for 60-90 min, and then performing heat treatment at 80 ℃ for 5-10 min to obtain a substrate A;
s3, performing oxygen plasma etching on the surface of the substrate A obtained in the step S2 for 15-30 min to change the smooth polymer microsphere array on the surface of the substrate A into a plush polymer microsphere array to obtain a substrate B; wherein the size of the plush gaps is not more than 30nm, the etching gas is pure oxygen, the flow rate is 20-40 sccm, and the power is 20-50W;
s4, depositing a layer of noble metal on the surface of the substrate B obtained in the step S3 by electron beam evaporation or thermal evaporation deposition, wherein the thickness of the noble metal is 15-30 nm, and obtaining a substrate C;
and S5, immersing the substrate C obtained in the step S4 in an acetone or chloroform solution for etching for 30-60 min to remove the plush polymer microsphere array between the precious metal layer and the substrate, and cleaning and drying to obtain the SERS substrate based on the 2D precious metal nanostructure.
3. The method for preparing a 2D noble metal nanostructure-based SERS substrate according to claim 1 or 2, wherein the substrate is SiO 12/Si, glass, quartz, GaAs, GaN, Si3N4SiC inorganic materials, or PDMS, PMMA, PI organic materials.
4. The method for preparing a 2D noble metal nanostructure-based SERS substrate according to claim 1 or 2, wherein the hydrophilic treatment step in step S1 is performed by uv ozone oxidation, oxygen plasma treatment or H at 80 ℃2O/H2O2/NH4Soaking in the OH mixed solution.
5. The method for preparing a 2D noble metal nanostructure-based SERS substrate according to claim 1 or 2, wherein the polymer microsphere in step S2 is polystyrene or PMMA.
6. The method for preparing a 2D noble metal nanostructure-based SERS substrate according to claim 1 or 2, wherein the diameter of the polymer microsphere in the step S2 is 0.5-3 μm.
7. The method for preparing a 2D noble metal nanostructure-based SERS substrate according to claim 1 or 2, wherein the etching gas is replaced by a mixed gas of oxygen and argon in step S3, wherein the flow rate of oxygen is 30-60 sccm, the flow rate of argon is 10-30 sccm, and the power is 20-50W.
8. The method for preparing a 2D noble metal nanostructure-based SERS substrate according to claim 1 or 2, wherein the noble metal is gold or silver in step S4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110087194.3A CN112921276B (en) | 2021-01-22 | 2021-01-22 | Preparation method of SERS substrate based on 2D noble metal nanostructure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110087194.3A CN112921276B (en) | 2021-01-22 | 2021-01-22 | Preparation method of SERS substrate based on 2D noble metal nanostructure |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112921276A true CN112921276A (en) | 2021-06-08 |
| CN112921276B CN112921276B (en) | 2022-03-15 |
Family
ID=76164654
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110087194.3A Active CN112921276B (en) | 2021-01-22 | 2021-01-22 | Preparation method of SERS substrate based on 2D noble metal nanostructure |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112921276B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102180438A (en) * | 2011-03-28 | 2011-09-14 | 中国科学院光电技术研究所 | Manufacturing method of tunable triangular metal nano particle array structure |
| CN102910576A (en) * | 2012-11-16 | 2013-02-06 | 重庆绿色智能技术研究院 | Method for producing high-sensitivity surface reinforcement Raman sensor chip |
| CN108456848A (en) * | 2018-03-28 | 2018-08-28 | 吉林师范大学 | A kind of Ag/FeS composite stratified materials SERS substrates and preparation method thereof |
| CN109856116A (en) * | 2019-02-28 | 2019-06-07 | 吉林大学 | A kind of classifying nano cone array and preparation method thereof using the chemical reaction of Surface enhanced Raman scattering in-situ monitoring |
| KR20200060578A (en) * | 2018-11-21 | 2020-06-01 | 한국과학기술원 | Block copolymer nanopattern and the method for preparing that |
| CN111426674A (en) * | 2020-03-16 | 2020-07-17 | 杭州电子科技大学 | Sunflower nano array structure for enhancing SERS activity and preparation method thereof |
-
2021
- 2021-01-22 CN CN202110087194.3A patent/CN112921276B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102180438A (en) * | 2011-03-28 | 2011-09-14 | 中国科学院光电技术研究所 | Manufacturing method of tunable triangular metal nano particle array structure |
| CN102910576A (en) * | 2012-11-16 | 2013-02-06 | 重庆绿色智能技术研究院 | Method for producing high-sensitivity surface reinforcement Raman sensor chip |
| CN108456848A (en) * | 2018-03-28 | 2018-08-28 | 吉林师范大学 | A kind of Ag/FeS composite stratified materials SERS substrates and preparation method thereof |
| KR20200060578A (en) * | 2018-11-21 | 2020-06-01 | 한국과학기술원 | Block copolymer nanopattern and the method for preparing that |
| CN109856116A (en) * | 2019-02-28 | 2019-06-07 | 吉林大学 | A kind of classifying nano cone array and preparation method thereof using the chemical reaction of Surface enhanced Raman scattering in-situ monitoring |
| CN111426674A (en) * | 2020-03-16 | 2020-07-17 | 杭州电子科技大学 | Sunflower nano array structure for enhancing SERS activity and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| MIN-ZHUO CHENG ET AL.: "Gold surface plasmon crystal structure based-on polystyrene template for biosensor application", 《ELECTROPHORESIS》 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112921276B (en) | 2022-03-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Yao et al. | Uniform periodic bowtie SERS substrate with narrow nanogaps obtained by monitored pulsed electrodeposition | |
| US9279759B2 (en) | Nanoparticle array with tunable nanoparticle size and separation | |
| KR101448111B1 (en) | A substrate for surface-enhanced Raman scattering spectroscopy and a preparing method thereof | |
| CN108844943B (en) | SERS unit and preparation method and application thereof | |
| Song et al. | Probing the mechanisms of strong fluorescence enhancement in plasmonic nanogaps with sub-nanometer precision | |
| CN103451610B (en) | Novel bionic Raman spectrum base and preparation method thereof | |
| CN102590179A (en) | Silver nano lattice surface enhanced raman active substrate and preparation method thereof | |
| Feng et al. | Silver-coated elevated bowtie nanoantenna arrays: Improving the near-field enhancement of gap cavities for highly active surface-enhanced Raman scattering | |
| Repetto et al. | SERS amplification by ultra-dense plasmonic arrays on self-organized PDMS templates | |
| CN107966429B (en) | Gold nanoring stacked array substrate with surface enhanced Raman scattering and preparation method thereof | |
| Chao et al. | Anti-reflection textured structures by wet etching and island lithography for surface-enhanced Raman spectroscopy | |
| Van Nguyen et al. | Improvement of SERS for detection of ultra-low concentration of methyl orange by nanostructured silicon decorated with Ag nanoparticles | |
| CN109612975B (en) | Surface-enhanced Raman substrate and preparation method thereof | |
| CN113296176B (en) | Surface-enhanced Raman scattering substrate and preparation method thereof | |
| Svavarsson et al. | Large arrays of ultra-high aspect ratio periodic silicon nanowires obtained via top–down route | |
| Fang et al. | Femtosecond laser structuring for flexible surface-enhanced Raman spectroscopy substrates | |
| CN108613959B (en) | SERS chip and preparation method thereof | |
| CN108611604B (en) | Manufacturing method of economical high-precision surface enhanced Raman active substrate based on high dielectric material | |
| Hu et al. | Preparation and SERS performance of gold nanoparticles-decorated patterned silicon substrate | |
| CN112921276B (en) | Preparation method of SERS substrate based on 2D noble metal nanostructure | |
| Jung et al. | Preparation of anodic aluminum oxide masks with size-controlled pores for 2D plasmonic nanodot arrays | |
| CN111650183A (en) | Surface-enhanced Raman scattering substrate and preparation method and application thereof | |
| CN111337471A (en) | Preparation method of SERS substrate based on nanoimprint and electrochemical deposition technology | |
| Ovchinnikov et al. | Self-organization-based fabrication of stable noble-metal nanostructures on large-area dielectric substrates | |
| Lancaster et al. | Surface preparation of gold nanostructures on glass by ultraviolet ozone and oxygen plasma for thermal atomic layer deposition of Al2O3 |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |