54 results about "Platinum nanoparticles" patented technology

The invention discloses a preparation method of an ionic liquid modified carbon sphere loaded platinum nanoparticle catalyst, and application of the catalyst to methanol electrocatalysis reaction. The method comprises the following steps of: synthesizing carbon spheres and ionic liquid; modifying the carbon spheres by using the ionic liquid; and performing anion exchange on a platinum precursor and the ionic liquid, and reducing platinum on the surfaces of the ionic liquid modified carbon spheres to obtain the ionic liquid modified carbon sphere loaded platinum nanoparticle catalyst. A catalyst modified glassy carbon electrode is taken as a working electrode, and electrochemical reaction is performed in electrolyte solution of sulfuric acid/methanol. The method can effectively prevent platinum nanoparticles from being agglomerated; and due to the introduction of the ionic liquid, the conductivity of the carbon spheres is further improved, specific surface area is increased, capability of resisting carbon monoxide poisoning can be improved, and the performance of a catalyst carrier is optimized.

Methanol-tolerant cathodic catalysts were prepared by depositing platinum nanoparticles and iron macrocycles on a carbon substrate. The order of depositing the iron and platinum on the carbon substrate were varied to form a (Fe—Pt)/C catalyst and a (Pt—Fe)/C catalyst. Different sintering temperatures were investigated to determine the heating effect on methanol tolerance. Oxygen reduction with and without the presence of methanol on these new catalysts was evaluated by using a rotating disk electrode system.

The invention discloses a preparation and application method of a titanium dioxide loaded highly dispersed platinum composite photocatalytic material, and belongs to the field of titanium dioxide photocatalysis. The preparation method comprises following steps: tetrabutyl titanate and hydrofluoric acid are stirred to be uniform at room temperature, an obtained mixture is reacted for 15 to 24h at 150 to 220 DEG C in a hydrothermal reaction kettle, and titanium dioxide nanosheets are obtained via separation, washing, and drying; the titanium dioxide nanosheets are dispersed in absolute ethanediol uniformly, and is subjected to reflux condensation stirring for 10 to 60min at 80 to 150 DEG C, polyvinylpyrrolidone and chloroplatinic acid are added, an obtained mixed material is subjected to reflux condensation stirring for 3 to 10h at 80 to 150 DEG C, and the titanium dioxide nanosheet loaded platinum nanoparticle composite material is obtained via separation, washing, and drying. The preparation method is capable of obtaining titanium dioxide nanosheets with a morphology easy to control; ethanediol is taken as a reducing agent, and 2 to 3nm platinum quantum dots with uniform particle size and high dispersity are obtained; the preparation parameters are easy to control; and repeatability is high. The titanium dioxide loaded highly dispersed platinum composite photocatalytic material is especially suitable to be used for catalytic degradation organic dyes under ultraviolet irradiation, and relatively high degradation rate is achieved.

This invention discloses a method for loading platinum metal nanometer particles in the carbon carrier surface, which comprises the following steps: a) scattering carbon carrier on the polyatomic alcohol liquid with platinum metal salt and acetate; b) heating to 160-180 Deg.c, stirring and refluxing 2-3 hours; wherein each liter liquid has 1.2-15 g carbon carrier, 0.01-0.04 mole metal salt, 0-0.01 mole acetate. The loading quantity of platinum metal nanometer particles in the carbon carrier surface is 2%-40%. The particles have fine and even grain size, and the average size is about 3.0nm; besides, the method does not need any surface activator or polyaromatics protecting agent.

The invention belongs to the technical field of mercury ion detection, and in particular, relates to a paper chip colorimetric analysis system for mercury ion detection and a construction method and an application thereof. The construction of the paper chip colorimetric analysis system includes the steps of preparation of a paper chip plastic bearing substrate, and design and preparation of the paper chip; the paper chip is similar to a micro reaction vessel and is used for platinum nanoparticle catalysis of a TMB/H2O2 developing reaction; the construction of a simple optical fiber analysis device is used for representation of the intensity of a color in the paper chip in a numerical value form. A principle comprises that platinum nanoparticles have excellent activity similar to catalase and can rapidly catalyze a TMB/H2O2 substrate to generate a blue precipitate, while when mercury ions exist, PtNPs can quickly undergo a reaction with the mercury ions to inhibit self enzyme activity, and finally, the recognition and quantitation of the mercury ions in the solution are achieved through changes of the color after the reaction. The system has the advantages of excellent specificity and selectivity, and has wide application prospect.

The invention relates to an electrochemical gas sensing device adopting a precious metal and graphene composite material as a sensing electrode and a production method of the electrochemical gas sensing device. The production method comprises the following steps: (1) preparing graphene oxide; (2) preparing a platinum metal nano particle and graphene composite material; (3) producing the sensing electrode in an electrochemical sensor: producing the gas sensor by adopting the platinum metal nano particle and graphene composite material as the sensing electrode of the electrochemical gas sensor. The gas sensor can detect various gases such as hydrogen and carbon oxide.

The invention discloses a platinum/attapulgite catalyst and a preparation method thereof. The carrier of the catalyst is the attapulgite clay; the active component of the catalyst is platinum nanoparticles of which the average particle size is 3 to 5 nm; the mass fraction of the platinum in the catalyst is 0.5 to 5 percent; and the residual component of the catalyst is the attapulgite clay. The preparation method comprises the following steps of: modifying the surface of the attapulgite clay with acid; adding a certain amount of modified attapulgite clay into aqueous solution of platinum salt; adjusting the pH value of the aqueous solution with sodium hydrate; adding aqueous solution of potassium borohydride or hydrazine hydrate dropwise in the aqueous solution under the action of magnetically stirring; filtering, washing and drying the mixed aqueous solution to obtain the platinum/attapulgite catalyst. The platinum/attapulgite catalyst prepared by the method of the invention is high in catalytic activity and selectivity for hydrogenation preparation of cinnamyl alcohol through cinnamaldehyde.

The invention discloses a reduced graphene oxide/porphyrin/platinum nano composite material and a preparation and application thereof and belongs to the technical field of photocatalysis. Reduced graphene oxide with good electric conductivity is adopted as a molecule of an anchor group, a reduced graphene oxide film is modified by adopting rodlike 5,10,15,20-tetra(4-carboxyphenyl) porphyrin with optimal photocatalytic performance in porphyrin, and platinum nanoparticles as an optimal catalytic dehydrogenation material are finally loaded on the modified reduced graphene oxide film. The prepared ITO-RGO-TCPP NR-PtNPs nano composite material has good photocatalytic performance and can be used as a catalyst in the photocatalytic hydrogen production capacity process; the whole method is short in technological process, simple in experiment condition, low in cost and free of pollution to environment; and the requirements of clean production are met.

The invention discloses a carbon nanotubes-supported nitrogen doped graphene-covering platinum nanometer compound material and a preparation method and application thereof, and belongs to the technical field of phenylacetylene selective hydrogenation reaction catalysts. A wet chemical reduction method is adopted for directly loading platinum nanoparticles onto carbon nanotubes subjected to acid treatment, a CVD method is used, nitrogen-doped graphene layers coat the surfaces of the platinum nanoparticles, and the number of the nitrogen-doped graphene layers is 2-7. Through the CVD method, thecarbon nanotubes-supported nitrogen doped graphene-coated platinum nanometer compound material is prepared, compared with traditional carbon nanotubes-supported Pt catalysts, a carbon nanotubes-supported nitrogen doped graphene-coated platinum nanoparticle catalyst can effectively catalyze conversion of phenylacetylene into styrene, and the hydrogenation selectivity and a conversion rate of the phenylacetylene are obviously improved; in the reaction process, inactivation is not prone to happen, and the cycling stability is good, wherein the carbon nanotubes-supported nitrogen doped graphene-covering platinum nanoparticle catalyst can be recycled for 4-5 times.

The invention belongs to the technical field of a precious metal catalyst, and discloses a polycarboxyl magnetic silicon nanosphere immobilized platinum catalyst as well as a preparation method and application thereof, wherein the catalyst is that platinum nanoparticles are uniformly dispersed on the surface of a polycarboxyl magnetic silicon nanosphere carrier; the preparation method adopts a nano ferrosoferric oxide magnetic sphere as a core; the nano ferrosoferric oxide magnetic silicon sphere is prepared by coating silicon dioxide by a sol-gel method, and carboxyl functionalization is performed to obtain a polycarboxyl magnetic silicon nanosphere carrier, and then the metal platinum is immobilized to obtain the polycarboxyl magnetic silicon nanosphere immobilized platinum catalyst. A cheap and easily available material is adopted as an immobilizing material, phosphorus or sulfur is not involved in the preparation process, and the polycarboxyl magnetic silicon nanosphere immobilizedplatinum catalyst is prepared which has high activity, selectivity and reusability and is successfully applied to hydrosilylation between n-hexene, n-heptylene, n-octylene, trans-2-hexene, cis-2-hexene, trans-3-hexene, cis-3-hexene and dichloromethylsilane.

The invention relates to a reusable enzyme-free glucose detection device and method and belongs to the field of electrochemical biological sensors. A sensor provided by the invention adopts a three-electrode system, wherein a titanium dioxide nanotube array film which modifies platinum nanoparticles serves as a working electrode, a platinum sheet serves as a counter electrode and an Ag/AgCl or 3 mol/L of KCl serves as a reference electrode; the three-electrode system works in an electrolytic tank, an H2SO2 solution with the concentration of 1 mol/L serving as electrolyte is added into the electrolytic tank, and the Pt electrode, the working electrode and the reference electrode are connected with an electrochemical analysis instrument respectively, so that detection can be performed; after detection is finished, a detection function can recover after irradiation is performed for 30 minutes under ultraviolet light; the lower limit of glucose detection is 4*10<-5> mmol/L. Compared with a traditional enzyme method, the enzyme-free detection method has the advantages that the detection limit is increased by above 90%. A novel, simple, convenient, quick, low-cost, stable and reusable enzyme-free glucose detection method is provided.

The invention relates to a method for preparing a catalyst for hydrogenolysis of biodiesel by-product glycerinum to produce 1,3-propylene glycol.The catalyst is platinum nano-particles (PtNPs) assembled in a hole channel of mesoporous alumina (mAl2O3) and modified by silicotungstic acid (HSiW), which is abbreviated as PtNPs-HSiW/mAl2O3.The method for preparing the catalyst comprises the steps that the PtNPs are added into an aluminum oxide synthesis system which is in a solvent evaporation induced self-assembly mode, and HSiW modification is conducted.The PtNPs are synthesized through an ethylene glycol reduction method, the solvent evaporation induced self-assembly system mainly comprises a template agent F108, aluminum oxide precursor sec-butyl alcohol aluminum and acid substance, and HSiW modification is conducted through an equivalent-volume impregnation method.By means of the catalyst, glycerinum can produce 1,3-propylene glycol in a hydrogenolysis mode.Due to the special structure that metal platinum in the catalyst is assembled in the carrier hole channel, compared with traditional catalysts, the catalyst has the advantages that the metal loss ratio is lower and the effect is more stable after being reused for multiple times.

The invention relates to a multi-metallic catalyst for catalyzing reforming reaction and a preparation method of the multimetallic catalyst, belonging to the technical field of catalysts. The catalyst is prepared from nickel-copper and platinum nanoparticles, aluminum oxide particles and a composite oxide carrier, wherein the nickel-copper and platinum nanoparticles are uniformly dispersed, and the composite oxide carrier is formed by calcining LDHs (Layered Double Hydroxides). A synergistic effect exists between metals, and the reforming performance of the catalyst can be effectively improved. The catalyst uses bimetallic composite hydroxides which are also known as Layered Double Hydroxides(LDHs) or LDHs loaded with a small amount of platinum as a catalyst precursor, and the molar ratio of Cu<2+> and Ni<2+> in divalent ions of a LDHs layer board is 0.5-3. The catalyst precursor is subjected to calcination reduction to obtain the catalyst. N-heptane is utilized for detecting the reforming performance of the catalyst, the highest n-heptane conversion rate is 85 percent, the methylbenzene selectivity is 16 percent, and the highest heterogeneous selectivity is 39 percent.

The invention relates to a biosensor for detecting Hx (hypoxanthine) in aquatic products and application thereof, and belongs to the field of food analysis. A fluorescence biosensor is built on the basis of the catalysis activity of Pt NPs (platinum nanoparticles), and is used for detecting the content of Hx in the aquatic products. A provided sensing system consists of XOD (xanthine oxidase), OPD(o-phenylenediamine) and Pt NPs; Hx reacts with oxygen under the existence of XOD to produce uric acid and H2O2; the Pt NPs can catalyze the oxidization reaction of the OPD and the H2O2 to produce 2,3-phenazine diamine giving out yellow fluorescence; and a fast, simple, convenient and sensitive aquatic product freshness degree detection method is provided. The novel detection method has the characteristics that the preparation of the Pt NPs is simple; the acquisition is easy; the simple and convenient analysis on the aquatic product freshness degree can be realized; the operation is simple; and the sensitivity and the selectivity are high. The popularization and the use are easy.

The present invention relates to a preparation method for a porphyra microcrystalline cellulose/nano platinum composite material, and belongs to the field of antimicrobial composite material preparation. The invention aims to solve the problems in a conventional platinum nano antimicrobial composite material preparation process that platinum nanoparticles are prone to agglomeration and cannot be uniformly dispersed on the surface of a material substrate, and thus an antibacterial effect is poor. The method disclosed by the present invention is characterized by comprising the steps of carrying out acid pickling on porphyra fiber and using calcium hypochlorite for bleaching, then carrying out second acid hydrolysis and alkaline leaching to prepare microcrystalline cellulose, taking ethylene glycol as a reducing agent and a reaction solvent to enable nucleation and growth of platinum nitrate nanoparticles, and uniformly distributing the nanoparticles on the surface of microcrystalline cellulose. Accordingly, the anti-bacterial performance is increased to 95% or higher.

The invention provides a nano-bioprobe for detecting pathogenic bacteria and a preparation method thereof. The nano-bioprobe is composed, in a coupling manner, a magnetic core-shell nanostructure anda specific recognition molecule targeted to the pathogenic bacteria; the magnetic core-shell nanostructure is prepared with a Fe3O4 particle being a core and a SiO2 layer, in which platinum nanoparticles are embedded, being a shell layer, the whole nanostructure carries negative electricity and has mimic peroxidase activity. The nano-bioprobe has the mimic peroxidase activity, so that existence ofthe pathogenic bacteria is quickly detected through a colorimetric method. The preparation method is simple in process, has good operability and is environment-friendly, wherein the nano-bioprobe canquickly detect the pathogenic bacteria and has excellent application prospect.

The invention relates to a single-stranded DNA/reduced graphene/cottony platinum nanoparticle as well as synthesis and application thereof. The synthesis method comprises the following steps: performing pyrolysis on milt DNA sodium salt to form single-stranded DNA, adding oxidized graphene to a single-stranded DNA solution under a pyrolysis temperature, stirring uniformly, and then adding trisodium citrate for reduction to obtain a reduced graphene solution modified by the single-stranded DNA; treating a glassy carbon electrode to be clean, dropwise adding the reduced graphene solution modified by the single-stranded DNA, and drying for standby use; using the obtained glassy carbon electrode as a working electrode, using a Ag/AgCl electrode as a reference electrode, using a platinum wire electrode as a counter electrode, performing electrochemical deposition in a chloroplatinic acid mixed solution, and synthetizing the single-stranded DNA/reduced graphene/cottony platinum nanoparticle. Compared with the prior art, the cottony platinum nanoparticle by using reduced graphene modified by the single-stranded DNA as a base synthetized by the synthesis method is used for a methanol fuel cell anode material, the poisoning problem of the methanol fuel cell anode material is successfully solved, and the catalytic property and poison resistance of the material are improved.

The invention discloses tumor microenvironment response type nucleus-targeting platinum nanoparticles comprising platinum nanoparticles and nucleus-targeting peptide and amphiphilic polymer modified on the platinum nanoparticles. The invention further discloses a preparation method of the tumor microenvironment response type nucleus-targeting platinum nanoparticles. The preparation method comprises the steps as follows: a platinum salt precursor and a blocking agent are dissolved in water to form a precursor solution, and a strong reducing agent is added for a reduction reaction to obtain subminiature platinum nanoparticles; amphiphilic polymers are dissolved in a good solvent, a modifier is added, and stirring reaction is conducted to obtain a n amphiphilic polymer is obtained; the subminiature platinum nanoparticles and nucleus-targeting polypeptide are dissolved in water, and stirring reaction is conducted to prepare nucleus-targeting platinum nanoparticles; and the nucleus-targeting platinum nanoparticles and the amphiphilic polymer are dissolved in water, and stirring reaction is conducted to obtain the tumor microenvironment response type nucleus-targeting platinum nanoparticles. The tumor microenvironment response type nucleus-targeting platinum nanoparticles can specifically target tumor cells, center cell nucleus to damage DNA and kill tumor cells.

The invention provides a Mn-PtM/C type platinum-based oxygen reduction catalyst and a preparation method and application thereof.The preparation method comprises the steps that a conductive carbon carrier with the large specific surface area is selected as a carrier, platinum nano-particles or platinum alloy nano-particles are loaded on the carbon carrier based on a polyol reduction method and with manganese as an auxiliary, and the Mn-PtM/C type platinum-based oxygen reduction catalyst is obtained; the Mn-PtM/C type platinum-based oxygen reduction catalyst is obtained through one-pot preparation, the preparation steps are simple, operation is convenient, and the yield reaches 90%; according to the prepared Mn-PtM/C type platinum-based oxygen reduction catalyst, Mn is used as an auxiliary agent, Mn and Pt do not form an alloy, the content of Pt is low, the cost is low, the addition of the auxiliary agent manganese plays a key role in reduction of platinum or platinum alloy, the dispersity and the particle size of the active component platinum nano particles or platinum alloy nano particles can be adjusted through the addition amount of Mn, and the stability and the stability of the catalyst are improved. The platinum-based oxygen reduction catalyst has improved oxygen reduction performance, and can provide high power density when applied to the field of batteries.

The invention discloses a preparation method of a carbon material loaded high-entropy alloy oxygen reduction electrocatalyst, which comprises the following steps of forming a coating layer for adsorbing metal ions on the surface of platinum carbon, and then dipping in a metal salt solution, wherein a metal source of the metal salt solution at least comprises four metal elements, and calcining the impregnated platinum carbon, melting metal ions into platinum nano-particles through thermal diffusion so as to form a high-entropy alloy, and then performing acid pickling and drying, thereby obtaining the electrocatalyst. According to the preparation method, platinum and carbon are used for high-entropy alloying, the subsequent carrier loading process is avoided, platinum is anchored to the surface of the carrier, moderate dispersity is achieved, thermal migration of platinum in the high-temperature calcination reduction process can be restrained, and alloy particles can keep small size and good dispersity; alloy types are not limited, and the universality is high; the half-wave potential of the prepared PtNiCoMnCe high-entropy alloy is 0.938 V which is superior to 49 mV of commercial platinum carbon, and the oxygen reduction performance is good.

A preparation method of a carbon-supported platinum nano-catalyst comprises the following steps: providing a strong base, a chlorine-containing platinum source, a carbon carrier and water, with the molar ratio of the strong base to the chlorine-containing platinum source being (3-10): 1; mixing the strong base, the chlorine-containing platinum source, the carbon carrier and water to obtain a dispersion liquid with the pH value of 11-14; drying the dispersion liquid to obtain carbon-supported platinum precursor powder; and placing the carbon-supported platinum precursor powder in a reducing gas, and heating to obtain the carbon-supported platinum nano-catalyst. The carbon-supported platinum nano-catalyst comprises a carbon carrier and platinum nano-particles uniformly and dispersedly anchored on the carbon carrier. The invention also provides a carbon-supported platinum nano catalyst, a catalyst layer and a proton exchange membrane fuel cell. The preparation method of the carbon-supported platinum nano-catalyst provided by the invention has the advantages of simple process, low cost, no pollution, high production efficiency, high catalytic efficiency, high platinum loading capacity, clean surface and good platinum nano-particle dispersity.