102 results about "Platinum nanoparticle" patented technology

The application discloses an electrochemiluminescence immunosensor for detecting interleukin-1 beta and a preparation method and application thereof, and comprises a three-electrode system of a working electrode, a reference electrode and a counter electrode; the working electrode is a modified electrode of CoAl layered double hydroxide, is loaded with platinum nanoparticles after being etched by alkali, and is obtained by fixing interleukin-1 beta antibodies and blocking non-specific sites; and a solution containing luminol is used as an electrolyte during detection of the immunosensor. The working electrode of the immunosensor takes oxygen-rich vacancy CoAl layered double hydroxide as a substrate, combines with platinum nanoparticles to realize EMSI effect, significantly enhances the electrochemiluminescence signal of a luminol-dissolved oxygen system, realizes quantitative detection of IL-1 beta by combining with specific antigen-antibody recognition, and has the characteristics of strong anti-interference ability, fast detection speed and good stability.

The invention discloses a method for detecting aflatoxin B1 in coffee based on colorimetric and photo-thermal dual modes of MXene (at) Pt nano-enzyme, which comprises the following steps: etching Ti3AlC2 by using LiF and HCl to obtain MXene, synthesizing platinum nano-particle modified MXene nano-enzyme (MXene (at) Pt) by using dopamine carbon dots and sodium borohydride as reducing agents and adopting an in-situ reduction technology, and detecting aflatoxin B1 in coffee by using the MXene (at) Pt nano-enzyme (MXene (at) Pt nano-enzyme (MXene (at) Pt nano-enzyme (MXene (at) Pt nano-enzyme (MXene (at) Pt). The MXene (at) Pt shows near-infrared light stimulation enhanced peroxidase-like activity and photo-thermal performance and can catalyze blue deepening and temperature rising of a substrate 3, 3 ', 5, 5'-tetramethyl benzidine (TMB), when aflatoxin B1 exists, POD-like activity of MXene (at) Pt nano-enzyme is inhibited, and colorimetric and temperature signals are reduced; a method for detecting the AFB1 by the colorimetric temperature dual-mode sensor is established, and the method has the characteristics of high sensitivity, strong specificity, simplicity and rapidness in operation and the like.

The invention discloses a method for synthesizing a platinum-based nitrogen-doped graphdiyne catalyst based on an atomic layer deposition technology and application of the platinum-based nitrogen-doped graphdiyne catalyst. Firstly, hexabromobenzene and calcium carbide are subjected to vacuum ball milling, calcination and purification to obtain a graphdiyne carrier, then the graphdiyne carrier and melamine are mixed and calcined to achieve nitrogen doping of the carrier, and then loading of platinum nanoparticles is accurately controlled through an atomic layer deposition technology. According to the method, the characteristics of an atomic layer deposition technology are utilized, deposition parameters and the number of cycles are controlled, uniform distribution and size control of Pt nano-particles on porous graphdiyne are achieved, and a nitrogen-doped graphdiyne carrier and the platinum nano-particles have a synergistic effect. The platinum-based nitrogen-doped graphdiyne catalyst prepared by the invention has the specific surface area of 734.8 m < 2 > g < 1 > and the average pore size of 8.68 nm, and shows excellent electrocatalytic activity and dynamic performance in reaction.

The invention discloses a nano-enzyme-SERS (Surface Enhanced Raman Scattering) bifunctional sensor for detecting colorectal cancer markers with high sensitivity as well as a preparation method and application of the nano-enzyme-SERS bifunctional sensor. The preparation method comprises the following steps: coating a layer of platinum (Pt) on the surface of gold nanoparticles (AuNPs) by utilizing a chemical reduction method so as to form gold-platinum nanoparticles (Au (at) Pt NPs); assembling the synthesized Au (at) Pt NPs into an aminated capillary tube through electrostatic adsorption, so as to prepare a capillary tube SERS (Surface Enhanced Raman Scattering) substrate; the surface of Au (at) Pt NPs is modified with a marker aptamer through an Au-S bond, and the nano enzyme-SERS dual-function sensor is prepared. In the presence of hydrogen peroxide (H2O2), the Au (at) Pt NPs can catalyze the oxidation of 3, 3 ', 5, 5'-tetramethyl benzidine (TMB) to generate oxidized TMB (oxTMB) with a strong SERS (Surface Enhanced Raman Scattering) signal. When Hcy exists, the reductive sulfydryl of Hcy consumes hydroxyl free radicals (. OH) generated by H2O2 decomposition, so that TMB oxidation is inhibited, and SERS signal intensity is weakened. A linear regression equation of the logarithm of the Hcy concentration and the signal intensity is drawn according to the SERS signal intensity, so that quantitative detection of the Hcy is realized.

The preparation method mainly comprises the following steps: dissolving chloroplatinic acid, lanthanum salt and manganese salt in water according to a certain proportion, adding a complexing agent, adjusting the pH value, and carrying out gelation, drying and high-temperature calcination to obtain a perovskite precursor; and treating in a reducing atmosphere, so that platinum atoms are selectively dissolved out from crystal lattices, high-dispersion platinum nanoparticles are formed on the surface, and finally, the composite catalyst with extremely low platinum loading capacity is obtained. According to the method, platinum species are stably anchored through the perovskite carrier, the platinum atom utilization rate and catalytic stability are remarkably improved, excellent electrocatalytic activity and durability are shown in the oxygen reduction reaction, and the method can be widely applied to energy conversion equipment such as zinc-air cells and fuel cells and has important practical application value.

The invention discloses a dysprosium-doped platinum-based catalyst and a preparation method and application thereof, and belongs to the technical field of battery materials.The preparation method of the dysprosium-doped platinum-based catalyst comprises the following steps that a dysprosium-containing carbon carrier is placed in a first solvent to be subjected to ultrasonic dispersion, and turbid liquid is obtained; adding a soluble platinum salt and a soluble transition metal salt into the turbid liquid, and mixing to obtain a mixed liquid; removing the first solvent in the mixed solution to obtain a solid product; and calcining and etching the solid product to obtain the dysprosium-doped platinum-based catalyst. The dysprosium-containing carbon carrier is adopted to load the platinum-based intermetallic compound, so that dysprosium and the platinum-based nanoparticles can realize relatively strong association and generate interaction among electrons, atom diffusion is further promoted, the crystallinity is improved, and the electronic structure of the platinum nanoparticles is favorably adjusted. The dysprosium-doped platinum-based catalyst is relatively high in internal order degree, and has relatively high activity and stability when being applied to an acidic ORR reaction.

This invention relates to the field of chemical hydrogen storage, and discloses a carbon-based catalyst, its preparation method and application, and a method for the dehydrogenation of methylcyclohexane. The catalyst comprises nitrogen (N), carbon (C), hydrogen (H), and platinum nanoparticles; the catalyst has the following properties: "Pt x C y N z H a The schematic chemical composition of the catalyst is shown in the figure, where z:a = 1.5~5; z:x = 5~50; z:y < 0.016; in the catalyst, nitrogen atoms are covalently bonded to at least two carbon atoms; nitrogen atoms are covalently bonded to hydrogen atoms; the carbon tetrachloride adsorption value (CTC) of the catalyst is ≥80%; in the XRD spectrum of the catalyst, the A of the Pt(111), (200), (220), (222) crystal plane diffraction peaks of the platinum nanoparticles is ≥85%, and A = (Pt(111) peak area) / (peak area of ​​Pt(111) + peak area of ​​Pt(200) + peak area of ​​Pt(220) + peak area of ​​Pt(222))) × 100%. This catalyst has good catalytic activity and low hydrogenolysis activity, making it particularly suitable for dehydrogenation reactions, such as the dehydrogenation reaction of alkyl-substituted cycloalkanes. It can effectively control the hydrogenolysis reaction during the dehydrogenation process and reduce the generation of by-products. It is especially suitable for the application of methylcyclohexane dehydrogenation reaction. After the dehydrogenation reaction, the conversion rate of methylcyclohexane is high, and the methane content in the product is <0.3wt%.

This invention belongs to the field of biosensing technology, specifically relating to a modified carbon fiber electrode for detecting dopamine, its preparation method, and its application. The modified carbon fiber electrode comprises a carbon fiber electrode onto which gold-platinum bimetallic nanoparticles and polydopamine are sequentially modified. The preparation method specifically includes: firstly, modifying the surface of activated carbon fiber filaments with chloroauric acid and sodium citrate to obtain Au@CF; then, modifying the Au@CF surface with ascorbic acid and chloroplatinic acid to obtain platinum nanoparticles, obtaining Au / Pt@CF; finally, immersing the Au / Pt@CF in a dopamine solution to coat the Au / Pt@CF surface with polydopamine, obtaining PDA@Au / Pt@CF. This electrode has advantages such as high sensitivity, low detection limit, strong anti-interference ability, good biocompatibility, and high mechanical stability, making it suitable for dynamic monitoring of dopamine in the living brain.

The application belongs to the technical field of fuel cells, and discloses a porous cerium fluoride catalyst, a preparation method and application thereof. The application adopts an impregnation method to synthesize a composite oxide precursor with silica as a template, obtains the composite oxide after calcination, and then adopts hydrofluoric acid etching and fluorination to prepare cerium fluoride. Finally, the porous cerium fluoride, a carrier, a platinum source aqueous solution and an alcohol solution are mixed to perform a hydrothermal reaction, and the porous cerium fluoride catalyst is obtained. The application etches away the template skeleton by using hydrofluoric acid to form a porous structure. The pore diameter of the cerium fluoride carrier is controlled by adjusting the concentration of the hydrofluoric acid, the specific surface area of the catalyst carrier is increased, more active sites are provided for the adsorption of platinum nanoparticles, the proton transmission speed is accelerated, the amount of noble metal is reduced, and the catalyst activity is improved.

The present application relates to the technical field of colorimetric detection and removal of heavy metals, and particularly relates to a preparation of porous organic material loaded with platinum nanoparticles and application of the porous organic material in colorimetric detection and removal of Hg 2+ The porous organic material comprises a porous organic polymer loaded with platinum nanoparticles, and the average particle size of the platinum nanoparticles is 2.65 nm; the porous organic material loaded with platinum nanoparticles provided by the present application has Hg 2+ activated oxyenzyme-like activity. Based on the Hg 2+ activated oxyenzyme-like activity, a method for colorimetric detection of Hg 2+ is constructed. The porous organic material can also remove Hg 2+ efficiently, and the removal rate is as high as 99.4%.

The invention relates to a preparation method and application of a three-dimensional flexible film-shaped nano enzyme. The nano-enzyme comprises a substrate film layer, wherein the substrate film layer comprises a graphene oxide nano-sheet layer and a first cationic polymer layer adsorbed on the surface of the graphene oxide nano-sheet layer; the metal nanoparticle layer is loaded on the substrate film layer, and metal nanoparticles of the metal nanoparticle layer have a core-satellite structure; wherein the core is platinum nanoparticles, and the outer surface of the core is coated with a second cationic polymer layer; the satellites are a plurality of Au (at) Pt nano microspheres loaded on the outer surface of the second cationic polymer layer. The nano-enzyme and the nano-enzyme label disclosed by the invention have a three-dimensional flexible structure and relatively strong colorimetric performance; the nano enzyme is large in contact area, relatively high in catalytic activity and relatively strong in stability. The three-dimensional flexible film nano-enzyme label mediated immunochromatography method disclosed by the invention can be suitable for different types of target analytes, and has a wide application prospect in the fields of clinical diagnosis and the like.

The invention provides an intelligent response type platinum nano contrast agent. The intelligent response type platinum nano contrast agent comprises an amphiphilic polymer with a Schiff base bond and oleylamine modified hydrophobic platinum nanoparticles wrapped by the amphiphilic polymer. Compared with an iodine-based CT contrast agent, the platinum nano contrast agent has good biocompatibility, the platinum element with a high atomic number has a higher X-ray mass attenuation coefficient, the amphiphilic PEG shell prolongs the blood circulation half-life period of the platinum nano contrast agent, the carried Schiff base bond can intelligently respond to tumor acidic microenvironment fracture, and the stability of the platinum nano contrast agent is improved. The released La-PtNPs are aggregated in situ through hydrophobic interaction, and enhanced CT imaging and radiotherapy sensitization of tumors can be realized at the same time.

The invention discloses an electrochemical sensor working electrode and a preparation method and application thereof, and belongs to the technical field of electrochemical sensing. Firstly, organic semiconductor micromolecules (PTCK) are prepared as organic ligands, then the organic semiconductor micromolecules, chloroplatinic acid and few layers of graphene oxide are prepared into a PTCK-Pt-GO compound through a hydrothermal method, and then the graphene composite film (P-Pt-G) loaded with platinum nanoparticles is prepared on the surface of a working electrode area through in-situ electrochemical reduction. According to the functionalized graphene composite film prepared through electrochemical reduction, platinum nanoparticles are uniformly dispersed, more catalytic sites can be exposed, the detection capacity of hydrogen peroxide is improved, and the functionalized graphene composite film can be applied to preparation of a high-sensitivity hydrogen peroxide electrochemical sensor. The preparation process provided by the invention is simple, and the sensor has relatively low detection line and good detection performance.

Disclosed herein is a battery for generating hydrogen. The battery comprises a working electrode; a reference electrode; a counter electrode; the electrolyte is sulfuric acid with the concentration of about 0.5 M; wherein the working electrode is prepared by coating a layer of ink on a glassy carbon electrode and air-drying the glassy carbon electrode; and the ink is prepared by mixing the TMD composite material decorated by platinum nanoparticles with a solution to form a mixture and carrying out ultrasonic treatment on the mixture, and the solution is composed of water, ethanol and 5% sulfonated tetrafluoroethylidene fluorinated polymer-copolymer dispersion according to a volume ratio of 4: 1: 0.1.

The application discloses a cobalt silicate modified platinum-based catalyst, a preparation method and application, and belongs to the technical field of industrial catalysts. The platinum-based catalyst comprises a carrier, a cobalt silicate modification layer generated in situ on the carrier, and platinum nanoparticles loaded on the cobalt silicate modification layer; the cobalt silicate modification layer is a continuous fibrous structure and is covalently combined with the carrier through Si-O-Co bonds. The cobalt silicate modification layer realizes anchoring and electron transfer of the platinum nanoparticles, makes the platinum in an electron-rich state, weakens adsorption on an alpha, beta-unsaturated aldehyde C=C bond, and strengthens selective adsorption on a C=O bond; when the catalyst is applied to selective hydrogenation of alpha, beta-unsaturated aldehydes, the conversion rate of cinnamyl aldehyde can reach 98.2%, the selectivity of cinnamyl alcohol can reach 92.0%, and the catalyst is suitable for hydrogenation of various alpha, beta-unsaturated aldehydes such as aromatic aldehydes, aliphatic aldehydes and furan aldehydes, and has excellent catalytic activity, selectivity and stability, and good industrial application prospect.

The invention discloses a platinum-loaded mesoporous carbon catalyst as well as a preparation method and application thereof, and belongs to the technical field of catalysts. According to the preparation method disclosed by the invention, the infiltration angle between the mesoporous carbon and water is adjusted by pre-treating the mesoporous carbon, so that the accurate regulation and control of the proportions of platinum nanoparticles inside and outside the pore channels of the mesoporous carbon carrier are realized by regulating and controlling the solvent composition of the platinum salt solution; and the platinum nanoparticles outside the pore channels can be coated with a complexing agent aqueous solution in a targeted manner, so that a miscellaneous carbon atom layer is formed on the surfaces of the platinum nanoparticles outside the pore channels. The miscellaneous carbon atom layer not only can reduce the activity attenuation of platinum nanoparticles outside the pore channels caused by sulfonate radical poisoning, but also can effectively inhibit the dissolution of the platinum nanoparticles in the oxygen reduction process, and finally, the stability of the catalyst is far superior to that of a commercial platinum-carbon catalyst.

The invention relates to the technical field of immunodetection, and discloses a tri-modal immunochromatography detection system based on bowl-shaped COF, the tri-modal immunochromatography detection system comprises a signal marker ABCPP, an immune probe, an LFIA test strip and a signal detection module; the signal marker ABCPP is composed of a bowl-shaped covalent organic framework, an aggregation-induced luminophor and mesoporous palladium-platinum nanoparticles. According to the invention, fluorescence enhancement of AIEgens and colorimetric and photothermal effects of mPdPt NPs are creatively integrated on a bowl-shaped COF single platform; the bowl-shaped COF not only serves as an optical cage to remarkably enhance fluorescence emission of BTDTA through space limitation, but also serves as optical energy gathering to enhance interaction between light and substances. In addition, energy transfer between the internal AIGens and the external mPdPt NPs synergistically amplifies the photothermal effect, so that the photothermal conversion efficiency is remarkably improved.

The invention provides a covered stent with a photo-thermal treatment function and a preparation method of the covered stent, and belongs to the technical field of medical instruments. The covered stent comprises a stent skeleton, a developing ring embedded in the stent skeleton and a photo-thermal conversion functional composite membrane, the composite film with the photo-thermal conversion function is of a three-layer sandwich structure and sequentially comprises an inner covering film, a middle functional layer and an outer covering film from inside to outside. And a stent inner cavity for contents to pass through is defined by the inner covering film. According to the invention, the platinum nanoparticles are adopted as the photo-thermal conversion material to prepare the photo-thermal treatment covered stent for the first time, and the stent has good photo-thermal conversion efficiency, so that the problems of loss of the photo-thermal material and limited load capacity of the photo-thermal material of the stent are solved, and accurate and controllable load of the photo-thermal material of the stent is realized.

This invention provides a hydrogen sensor based on nanoparticles, its preparation method, and its application, belonging to the field of hydrogen sensor technology. The nanoparticle-based hydrogen sensor provided by this invention includes a substrate and at least one pair of electrodes spaced apart on the surface of the substrate. The substrate surface between the electrodes is covered with nanoparticles, and the electrode surfaces and nanoparticle surfaces are covered with a thin film layer. The nanoparticles include one or more of palladium nanoparticles, platinum nanoparticles, and alloy nanoparticles, wherein the alloy nanoparticles contain palladium and / or platinum. The material of the thin film layer includes one or more of polymethyl methacrylate, naphthol, silica, alumina, polytetrafluoroethylene, diamond-like carbon film, silicon nitride, and silicon carbide. The nanoparticle-based hydrogen sensor provided by this invention has high sensitivity and excellent stability, enabling rapid and accurate determination of hydrogen in an air environment.

A pharmaceutical composition for targeted radionuclide therapy comprising a plurality of nanostructures. Each respective nanostructure may comprise a hydrophilic inner cavity and an outer shell of PEG. The hydrophilic inner cavity may comprise a colloidal solution of Lu-177 DOTATAE and a plurality of high-atomic-number nanoparticles selected from a group consisting of gold nanoparticles, platinum nanoparticles and tantalum nanoparticles with a maximum diameter of 1 to 20 nm in a aqueous medium with a ratio (Lu-177 DOTATE: the plurality of high- atomic-number nanoparticles) of 1: 50-60. The outer shell of PEG may have a surface charge between -0.1 and -0.3 mV. The plurality of high-atomic-number nanoparticles may have a diameter of 20 nm. Each respective nanostructure may have a diameter between 50 and 200 nm. Each respective nanostructure may have a diameter of 150 nm. The aqueous medium may be selected from a group consisting water and acetone.

The application discloses a method for colorimetric and photothermal dual-mode detection of aflatoxin B1 in coffee based on MXene@Pt nanozyme, wherein MXene is obtained by etching Ti3AlC2 with LiF and HCl, dopamine carbon dots and sodium borohydride are used as reducing agents, and in-situ reduction technology is adopted to synthesize MXene nanozyme modified with platinum nanoparticles (MXene@Pt). The MXene@Pt shows peroxidase-like activity and photothermal performance enhanced by near-infrared light stimulation, can catalyze the blue deepening of the substrate 3,3',5,5'-tetramethylbenzidine (TMB) and temperature rise, and when aflatoxin B1 exists, the POD-like activity of the MXene@Pt nanozyme is inhibited, and the colorimetric and temperature signals are reduced. The colorimetric and temperature dual-mode sensor detection method for AFB1 is established, and the method has the characteristics of high sensitivity, strong specificity, simple operation, rapidness and the like.

The application discloses a hollow spherical composite catalyst Pt / MnO2 / MnCo2O4, wherein the MnCo2O4 is a hollow sphere with a spinel structure composed of manganese and cobalt double transition metal oxides, the diameter of the hollow sphere is distributed in 1-2 mu m, and the hollow sphere has a porous structure with many cavities in the inside. MnO2 nanosheet microspheres are uniformly attached to the MnCo2O4, and the diameter of the MnO2 nanosheet microspheres is 95-105 nm. Pt nanoparticles with a particle size of 2-20 nm are uniformly loaded on the MnCo2O4 and the MnO2. The Pt / MnO2 / MnCo2O4 is synthesized by a solvothermal method and calcination in an air bath to synthesize a hollow spherical MnCo2O4 carrier, and then the MnO2 and the Pt nanoparticles are loaded on the surface of the MnCo2O4 by a deposition-precipitation method and an in-situ reduction method. The hollow spherical composite catalyst can catalyze degradation of tetracycline in polluted water at room temperature, and the catalytic efficiency can still be maintained after repeated use.

The invention provides a Pt / PEDOT composite modified carbon-based material needle-shaped electrode in-vivo dissolved oxygen electrochemical sensor as well as a construction method and application thereof, and belongs to the technical field of medical biology. According to the in-vivo dissolved oxygen electrochemical sensor, a carbon-based material microneedle type electrode is modified by electrochemical deposition of platinum nanoparticles by using a chloroplatinic acid hexahydrate solution and depending on a time current method, and poly (3, 4-ethylenedioxythiophene) is generated by direct electro-polymerization on the surface of the Pt-modified microneedle electrode through an electrochemical constant current method. And forming uniform PEDOT (poly (3, 4-ethylenedioxythiophene)) film coated and modified platinum nanoparticles on the microneedle electrode. The composite modified carbon-based material is used for replacing precious metal to reduce cost and improve biocompatibility, low-oxygen sensitivity is optimized by means of composite modification, in-vivo protein adsorption and biological membrane coverage are resisted through anti-pollution surface modification, and therefore the defects are overcome, and monitoring of in-vivo tissue oxygen partial pressure is achieved.

The invention discloses a low-platinum high-stability membrane electrode and a preparation method thereof, and belongs to the technical field of fuel cells. The membrane electrode comprises a proton exchange membrane, a catalyst layer and a gas diffusion layer, wherein the catalyst layer is composed of a Ti3C2TXMXene matrix, platinum nanoparticles and zirconium-doped cerium oxide nanoparticles. The surface of the MXene is subjected to plasma treatment to form a nitrogen-oxygen co-doped layer, and the nitrogen-oxygen co-doped layer is vertically aligned to form a porous network structure; the platinum nanoparticles are uniformly dispersed on the surface of the MXene; ce0. 8Zr0. 2O2 nano-particles are embedded between the MXene layers, so that high oxygen vacancy concentration is achieved. Through the synergistic effect of the ternary material, high electrochemical activity is kept while low platinum loading capacity is realized; the high conductivity of MXene and the nitrogen-oxygen co-doped layer effectively anchor platinum nanoparticles, so that the stability is remarkably improved; the high oxygen vacancy concentration of Ce0. 8Zr0. 2O2 can efficiently capture free radicals, so that the proton exchange membrane is protected.

The application provides a graphitized carbon supported platinum nanoparticle, a preparation method and application thereof. The graphitized carbon supported platinum nanoparticle comprises a graphitized carbon carrier, platinum nanoparticles supported on the graphitized carbon carrier, and carbon and sulfur independently supported on the graphitized carbon carrier or the platinum nanoparticles. The application introduces carbon and sulfur onto the graphitized carbon carrier and / or the platinum nanoparticles, wherein carbon atoms form a carbon package on the surface of the platinum nanoparticles, ensuring that the platinum nanoparticles are uniformly dispersed and small in size, and sulfur atoms can be coordinated with platinum, so that the platinum nanoparticles are mainly combined with the graphitized carbon carrier through platinum-sulfur bonds, thereby making up for the problem of low loading rate of the graphitized carbon carrier on the platinum nanoparticles, and making the graphitized carbon supported platinum nanoparticle have a high electrochemical active area. As a cathode catalyst of a proton exchange membrane fuel cell, the graphitized carbon supported platinum nanoparticle has excellent catalytic performance and significantly better start-stop cycle durability than a commercial Pt / C catalyst.

The application discloses a preparation method of a dendritic T-NC and ionic liquid Pt / C catalyst and application thereof, and generates a zeolite imidazolate framework material (ZIF-8) by reacting a zinc salt with 2-methyl imidazole, and composites the ZIF-8 with a conductive carbon material. When high-temperature pyrolysis is carried out under an inert atmosphere, zinc species in the ZIF-8 volatilizes, thereby etching out abundant multi-stage pores in the carbon matrix, and forming a unique dendritic nitrogen-doped carbon structure (T-NC). The structure can effectively load and stabilize platinum nanoparticles. Subsequently, by infiltrating ionic liquid, the high ionic conductivity and interface characteristics of the ionic liquid are utilized to enhance the proton conduction of a catalytic layer and optimize a mass transfer process. The method is simple in process, and raw materials are easy to obtain. Through the synergy of the carrier structure and the interface microenvironment, the prepared catalyst realizes comprehensive improvement in oxygen reduction reaction activity, durability and low-humidity adaptability, and provides a feasible material solution for a high-performance, long-life and low-cost proton exchange membrane fuel cell.

The invention discloses a gold-platinum alloy modified carbon fiber microelectrode and a preparation method and application thereof. The surface of a single carbon fiber is modified with gold-platinum nanoparticles to prepare a gold-platinum alloy modified carbon fiber microelectrode, and the gold-platinum alloy modified carbon fiber microelectrode is inserted into a cell to detect the concentration of hydrogen peroxide in the cell. The surface hydrophilicity and hydrophobicity regulation of the gold-platinum alloy modified carbon fiber microelectrode (modified gold-platinum nanoparticles) greatly increases the anti-fouling performance of the electrode surface, and when the contact angle is greater than 90 degrees, the good anti-fouling performance is maintained.

The present application belongs to the technical field of metal nanometer catalytic material, and particularly relates to a preparation method of a xanthium-like mesoporous carbon loaded platinum alloy catalyst and application thereof. The method for preparing the platinum-based alloy catalyst comprises the following steps: firstly, preparing a nano-carrier; then, using active hydrogen generated by photocatalysis to reduce and prepare platinum nanoparticles, and loading the platinum nanoparticles on the nano-carrier; and finally, preparing the platinum-based alloy catalyst through evaporation and calcination. The preparation method has the advantages of cheap reactants, simple preparation process, low energy consumption, and less pollutant emission. The platinum-based alloy catalyst prepared by the method has the advantages of good catalytic performance, good stability, long service life, and the like, has the potential for large-scale production and application, and has a wide application prospect.

This invention discloses a chiral gold-silver-platinum alloy nanomaterial, its preparation method, and its applications, relating to the field of metal nanomaterials technology. The invention includes: a substrate, wherein the substrate is chiral helical gold-silver alloy nanoparticles, and the substrate has a left-handed or right-handed helical morphology; and platinum nanoparticles, wherein the platinum nanoparticles are selectively deposited on the helical edges of the substrate by photodeposition, and the chiral helical morphology of the substrate is preserved after deposition. The photodeposition method is a photodeposition reaction performed under circularly polarized light irradiation with a specific helical direction. This invention provides more active sites for catalytic reactions and effectively avoids the displacement etching of the gold-silver alloy shell by platinum in traditional deposition methods, preserving the complete helical chiral structure.

The invention relates to the technical field of biosensing, and particularly discloses an implantable flexible microneedle sensor for continuously monitoring glucose and uric acid, the sensor comprises a flexible substrate, and a reference electrode, a counter electrode, a glucose detection working electrode and a uric acid detection working electrode which are integrated on the flexible substrate and share the reference electrode and the counter electrode, and synchronous detection is carried out under a unified potential window of + 0.1 V to + 0.2 V. A glucose oxidase (GOx) enzymology detection scheme is adopted in the detection method, GOx complex liquid is fixed after modification of a polypyrrole layer and a platinum nanoparticle layer, and specific glucose recognition is achieved; and the high-selectivity adsorption of uric acid is realized by adopting a molecularly imprinted polymer (MIP) non-enzymatic scheme and constructing a polyaniline / carbon nanotube composite layer and an MIP membrane. Through triple innovation of an identification mechanism, a potential design and an integrated structure, the core problems of insufficient selectivity, signal crosstalk and serious interference are solved, minimally invasive in-situ continuous monitoring is realized, and the anti-interference performance and the accuracy of synchronous detection are improved.