35results about How to "Excellent SERS performance" patented technology

The invention belongs to the field of preparation of nano porous metal materials, and relates to a method for preparing nano porous silver based on an Ag-based amorphous alloy. By the method, the nano porous silver with the aperture of 20-100 nm is finally obtained by preparing a series of Ag-Mg-Ca amorphous alloy thin bands by taking the Ag-based amorphous alloy as a precursor by a solvent quick quenching method and then removing Mg and Ca elements by performing electric chemical alloy component corrosion removal by proper electrolyte. By the method, the structure and the size of the nano porous silver are adjusted and controlled by controlling the amorphous alloy components or electric chemical corrosion temperature; the operation technology is simple; and furthermore, the nano porous silver is extremely high in surface-enhancement raman scattering (SERS) performance and has a wide application prospect in the fields of environment friendliness, catalysis and biological sensors.

The invention discloses a preparation method of a silver-based composite nanomaterial with surface-enhanced Raman activity, a product obtained with the preparation method and an application of the silver-based composite nanomaterial. The preparation method comprises preparation steps as follows: silver ions and melamine have a coordination polymerization reaction in water, and a coordination polymer is obtained; the coordination polymer is reduced with a sodium borohydride solution, nanosilver is generated on the surface of the coordination polymer, a layer of metal oxide is deposited on the surface of the reduced intermediate product, the deposited product is calcined, and the silver-based composite nanomaterial is obtained. The intermediate product with good morphology is obtained through the simple coordination polymerization reaction, silver sources can be uniformly dispersed in the intermediate product, the intermediate product is taken as a sacrificial template, and the silver-based composite nanomaterial with good morphology is obtained through metal oxide deposition and calcination. A process is simple, particle sizes of the obtained nanosilver particles are small, the nanosilver particles are distributed in a concentrated manner and are not prone to agglomeration under the protection of metal oxide, the stability is high, the SERS (surface-enhanced Raman scattering) effect is remarkable, and the silver-based composite nanomaterial has wide application prospect.

The invention provides a plasma metal-semiconductor composite film and its preparation method and its application in the detection of non-edible pigments, belonging to the technical field of spectral analysis. The main content of the present invention includes the preparation of plasma metal film and semiconductor material, by covering plasma metal film Au@Ag NP film with semiconductor ZnGeO:Sr NRs to prepare Au@Ag NP film@PLMs composite film, the plasma metal-semiconductor structure can be significantly enhanced SERS signal, so as to realize the detection of non-food coloring in food. The plasma metal-semiconductor composite film prepared by the invention can effectively amplify the SERS signal of the analyte, and has high accuracy and sensitivity.

The invention discloses a magnetic composite particle, a preparation method and application thereof. The magnetic composite particle has a core-shell satellite structure, including silver-shell magnetic beads and gold nanorods. The surface of the silver-shell magnetic beads is combined with gold nanorods through poly(2-vinylpyridine); It consists of a silver shell continuously coated on manganese ferrite. The preparation method of magnetic composite particles includes (1) adding silver-shell magnetic beads to poly(2-vinylpyridine) solution and ultrasonic treatment to obtain poly(2-vinylpyridine)-modified silver-shell magnetic beads; (2) preparing gold Nanorod solution; (3) Mix poly(2-vinylpyridine)-modified silver-shell magnetic beads with gold nanorod solution, and react with ultrasound to obtain magnetic composite particles, which can be used as SERS-enhanced substrates for detection applications. The magnetic composite particle of the invention has good magnetic response capability and SERS performance, and the preparation method is simple in process, strong in versatility and wide in applicability.

The invention discloses a preparation method of a micro pinpoint-shaped solid-phase surface enhanced Raman substrate. The preparation method comprises the following steps of (1) preparing carbon fiberprovided with a hole structure and modified by a functional group, (2) preparing a bonding body, (3) preparing a combining body, (4) preparing an electrode and (5) preparing the micro pinpoint-shapedsolid-phase surface enhanced Raman substrate, wherein a to-be-detected object such as pesticide residues in food can be rapidly separated and analyzed when the micro pinpoint-shaped solid-phase surface enhanced Raman substrate and a thin-layer chromatography are combined in use. The preparation method is simple in preparation process and easy to implement; the prepared micro pinpoint-shaped solid-phase surface enhanced Raman substrate is of a pinpoint-shaped macrostructure and has an excellent Raman enhancement property, with a Raman scattering enhancement factor reaching 107; since the sizeis small, sampling is convenient and sampling modes are flexible, the damage to a target object is small, the usage amount of samples is low, and the sensitivity is high; the micro pinpoint-shaped solid-phase surface enhanced Raman substrate is easily placed in other equipment and coupled with other technologies like the thin-layer chromatography, and is used for is used for the target object in acomplex system.

In the preparation method of AgNR / O-g-C3N4 substrate, O-g-C3N4 modification is carried out on the surface of AgNR to prepare multi-performance nanostructures for sensitive and recyclable SERS analysis. The AgNR / O-g-C3N4 substrate prepared by the preparation method and application thereof in recyclable SERS sensitive detection is disclosed. The method for preparing the AgNR / O-g-C3N4 substrate provided by the invention is simple; in the AgNR / O-g-C3N4 substrate provided by the invention, the O-g-C3N4 on the AgNR / O-g-C3N4 substrate can improve the adsorption capacity of the molecule and improve the SERS performance of the AgNRs and can avoid direct contact between AgNR and the atmosphere which improves the stability of AgNRs; the AgNR / O-g-C3N4 substrate of the invention can produce a significant Raman enhancement effect, and the SERS signal intensity obtained from AgNR / O-g-C3N4 is about three times stronger than unmodified AgNR, and the SERS signal intensity has high reproducibility and stability, has excellent photodegradability, and can perform multiple cycles of detection.

The invention relates to SERS-based magnetic test paper for detecting nitrite as well as a preparation method and a use method thereof. The magnetic test paper comprises a super-hydrophobic film, goldnanorods and a magnetic composite, wherein the gold nanorods are erected on the surface of the super-hydrophobic film in bundles after self-assembling; the magnetic composite is entrained among the gold nanorods. The gold nanorods and the magnetic composite are self-assembled on the surface of the super-hydrophobic material to form the magnetic test paper with excellent SERS property. 4-amino thiophenol adsorbed on the surface of the magnetic test paper is coupled with to-be-detected nitrite, and an SERS signal of a coupling product is utilized, so that quantitative and qualitative detectionon the nitrite is conducted indirectly. The magnetic test paper prepared by the method is corrosion-resistant and staining-resistant, has excellent SERS property and magnetism, is convenient to carry,can be rapidly separated out of a complex system under the action of an external magnet, and has wide application prospect in on-site, rapid and high-sensitivity detection on the nitrite in complex samples such as food, environments and biological samples.