30results about How to "Enhanced Raman activity" patented technology

The invention discloses a preparation method of a gold-silver composite nanoring. The preparation method comprises the following steps: placing a silver target material in water while stirring, and irradiating the silver target material for 10-30 minutes by using laser with the wavelength of 1064nm, the power of 30-50mJ/pulse, the frequency of 5-15Hz and the pulse width of 5-15ns to obtain a silver nanoparticle colloid solution; then, irradiating the silver nanoparticle colloid solution for 2-4 minutes while stirring by using laser with the wavelength of 532nm, the power of 34-38mJ/pulse, the power of 5-15Hz and the pulse width of 5-15ns to obtain a monodisperse silver nanoparticle colloid solution; then, adding the monodisperse silver nanoparticle colloid solution to a 0.13-0.17mmol/L chloroauric acid according to a volume rate being (0.8-1.2): (0.8-1.2), and stirring for at least 30 minutes to prepare the gold-silver composite nanoring in which a silver nanoring is modified with gold nanoparticles, wherein the ring diameter of the silver nanoring is 10-25nm, the thickness of the silver nanoring is 3-6nm and the particle diameter of the gold nanoparticles is 3-5nm. The gold-silver composite nanoring prepared by the preparation method disclosed by the invention is expected to be applied to a Raman detection technology based on a near-infrared excitation SERS (Surface Enhanced Raman Scattering) effect.

The invention belongs to the technical field of function materials, and specifically relates to a Raman strengthening active microsphere and a preparation method and an application thereof. The Raman strengthening active microsphere provided by the invention has a core-shell structure, the core of the Raman strengthening active microsphere is a melamine resin microsphere, and the shell is uniform and compact silver nanometer granules. The preparation method comprises the steps of firstly preparing uniform melamine-oxymethylene microsphere through fasculation, then utilizing a reducing agent to restore silver nitrate through a normal position chemical reduction method, and uniformly and compactly depositing the generated silver nanometer granules onto the surface of the melamine resin microsphere, so as to prepare the MF/Ag-NPs composite microsphere. The raman strengthening active microsphere utilizes a single microsphere as a raman strengthening base material, and is used for detecting Raman. The single Raman strengthening active base material microsphere provided by the invention has the characteristics of high stability and high Raman strengthening property. The method provided by the invention has the advantages that the operation is simple, the process is controllable, and the prepared composite microsphere can be used for analyzing and detecting organic contaminants such as pesticide residue of a single microsphere in a Raman manner.

The present invention discloses a quaternary hybrid magnetic composite functional material and a preparation method thereof. The composite material is a quaternary hybrid of Ag@AgX, reduced graphene oxide and magnetic nanomaterials. First, the surface of the rGO is sequentially in situ deposited with Fe3O4, MnFe2O4, ZnFe2O4, CoFe2O4 and other iron-based magnetic nanomaterials and grown with AgX precipitate so as to obtain rGO/MFe2O4/AgX ternary complex nanomaterials; and then the ternary complex nanomaterials are exposed to a mercury lamp to obtain the quaternary hybrid magnetic composite material rGO/MFe2O4/Ag@AgX. The material not only has the magnetically responsive property and externally applied magnetic field controllability of magnetic particles, the high adsorption performance, electrical conductivity and other properties of graphene nanomaterials, the photocatalytic property of plasma material Ag@AgX, but also has the surface enhanced raman spectroscopy activity of Ag particles, and the synergistic effect between Ag@AgX and graphene materials enhances the photocatalytic property of Ag@AgX and the SERS activity of Ag, so that the detection limit of the substance to be detected is increased. The material has great potential application value on one-step concentration, magnetic separation, SERS detection and in situ photocatalytic degradation and other aspects of low concentrations of benzene ring organic pollutants in water.

The invention discloses a large-area metal nano-structural substrate for surface-enhanced Raman and a preparation method thereof. The large-area metal nano-structural substrate for the surface-enhanced Raman consists of a nano-scale structural substrate consisting of different phase alloy materials and a nano-thickness metal material deposited on the substrate. The metal nano-structural substrateprovided by the invention has good Raman enhancing effect, and can be widely applied in the fields of physics, chemistry, materials science, biomedicine and the like. The preparation method for the large-area metal nano-structural substrate for the surface-enhanced Raman uses an alloy material consisting of different phases as a primary template, adopts a selective plasma etching method to etch the nano-structural substrate, and then adopts an ion beam sputtering method to deposit the nano-thickness metal material on the nano-structural substrate so as to form the surface-enhanced Raman substrate based on different phase metal materials; and the preparation method has mature industrial technology and low production cost, and can implement industrialized mass production.

The invention provides a preparing method for a metal/oxide compound surface enhanced Raman active substrate. The method solves the problem that according to an existing technical scheme, a metal/oxide compound substrate with a multilayer film structure is hard to prepare, meanwhile, the preparing method can be suitable for compounding of a plurality of kinds of metal and oxides, and the application range is wide. According to the method, firstly, a self-assembly technology is used for preparing a two-dimensional ordered polystyrene colloidal array; then, a plasma etching technology is used for etching the two-dimensional ordered polystyrene colloidal array; thirdly, the polystyrene colloidal array subject to treatment in the second step serves as a substrate, and under the protection atmosphere or vacuum conditions, a metal/oxide compound multi-layer film sequentially grows on the surface of the substrate through a magnetron sputtering method; and finally, heat treatment is carried out under the protection atmosphere, and the surface enhanced Raman activeness of the metal/oxide compound surface enhanced Raman active substrate obtained after special heat treatment is obviously enhanced.

The invention relates to a preparation method of silver nano particle coated zinc oxide nano tube substrate. The preparation method adopts a combination of a chemical method and a magnetron sputtering method. The target product Ag@ZNT substrate is prepared from following raw materials: Zn(OOCCH3)2.2H2O, Zn(NO3)2.6H2O, KCl, absolute ethanol, hexamethylene tetramine, and silver target. The substrate has the advantages of very good Raman activity, stability and repeatability, is an ideal SERS substrate, and is capable of being applied to fields of chemistry, materials science, and biomedicine.

The present invention relates to a preparation method for golden micro-crystal with a branchy surface with enhanced Raman scattering activities. The present invention uses disodiumedetate (Na₂EDTA) as reductant and appearance controlling reagent for the first time, three kinds of gold micro-crystal are prepared through the mixing of the disodiumedetate and hydrochloroauric acid (HAuCl₄) at different temperatures, and the three kinds of gold micro-crystal have a novel branchy surface and a micron sized measurement. The operation of the method is simple, and the prepared gold micro-crystal has high surface-enhanced Raman scattering activitiesand application value in the analysis field.

The invention relates to a method for detecting residual organics on a fire scene based on a surface enhancing raman spectrum. The method comprises the following steps: constructing a detection substrate material which comprises a metal film and a nanometer particle, wherein the surface of the metal film is modified with functional groups, the metal film has a hydrophobic effect and is smooth and flat, and the nanometer particle has surface enhancing raman activity and is free from modification with the functional groups; dropwise adding the filtration liquid onto the surface of the metal film with the hydrophobic effect; after finishing the dropwise adding, naturally volatilizing the liquid; dropwise adding the colloid containing the nanometer particle with the surface enhancing activity on the surface of the metal film and utilizing a raman spectrometer to detect the colloid on the surface of the metal film; comparing and analyzing the acquired spectrum chart and identifying the category of the organic compound in the to-be-detected article. According to the method, the operation is simple and convenient; the detecting base structure is simple and can be directly used for extracting, absorbing and enriching the analyte in the solution sample; the designed and constructed enhancing system can realizably acquire high-quality SERS test result; the method has the advantages of high sensitivity, excellent repeatability, zero background interference, and the like.

The invention relates to a metal nano porous structure. The metal nano porous structure comprises a nanocluster which is coordinated with a capillary tip; the nanocluster comprises spherical, flaky orpunctured nano branches, holes or pore channels are formed among the nano branches, and the metal is preferably gold, silver or copper. The preparation method comprises the following steps that a reducing agent solution is dispersed into a metal compound aqueous solution from the capillary tip so that the nano porous structure can be prepared at the capillary tip in situ. The metal nano porous structure has the advantages that the preparation method is simple, low in cost, the structural morphology is controllable, and movement and locating are convenient; and meanwhile, the metal nano porousstructure has the advantages of high raman optical activity and the like, and has wide application in the fields of life analysis, device sensing, single molecule detection and the like.

The invention discloses a surface enhanced Raman substrate material for detecting the water content of an organic solvent, and a preparation method and an application thereof. The preparation method comprises the following steps: (1) modifying polyvinyl alcohol gel with a p-aminothiophenol derivative 4,4'-dimercaptoazobenzene as a probe molecule; (2) preparing PVA-DMAB microspheres with uniform particle sizes and smooth surfaces in a micro-reactor; and (3) loading nano-silver particles on the surfaces of the PVA-DMAB microspheres through in-situ growth in order to prepare the PVA-DMAB-Ag Ramansubstrate material. The preparation method is simple, and the prepared Raman probe can realize the rapid, quantitative and qualitative analysis of water in the organic solvent, has the advantages ofrepeated use and low detection sensitivity, and has a great application prospect in the field of analysis and detection of a micro or trace amount of water.

The invention provides a SERS substrate material and a preparation method thereof. The preparation method comprises the following steps: preparing a nanometer alumina coating with a certain thickness and uniform pore size distribution from boehmite; impregnating the coating in a precious metal precursor solution; and carrying out deposition and immobilization of precious metal nanoparticles by using a method employing a combination of a reducing agent and irradiation by a high-pressure mercury lamp. The method uses cheap raw materials, is simple in process and has easily controllable process conditions; and the obtained SERS substrate material has good stability and uniform hot spot distribution and shows high sensitivity and repeatability in ultralow-concentration detection.

The invention discloses surface-enhanced Raman substrate microspheres with a micron size and a preparation method thereof, which belong to the technical field of a composite material. According to theinvention, PGMA is taken as a microspheres base material, a precipitation polymerization method and an in-situ reduction deposition technology are employed, sodium borohydride, cuprous oxide, cuprouschloride or n-butylamine are taken as reducing agents, Ag-NPs is deposited at the surface of PGMA microspheres, and the PGMA/Ag-NPs surface-enhanced Raman substrate microspheres can be formed. The substrate microspheres have strong surface-enhanced Raman activity for Raman label molecules such as p-aminothiophenol (ABT), p-chlorothiophenol (CBT), and thiohydroquinone (HBT), and have good application prospect on the chemical, food and biological detection aspects.