67 results about "Palladium atom" patented technology

The invention relates to a catalytic hydrodechlorination Pd-M/NOMC catalyst and a preparing method and application thereof. According to the catalyst, with synthetic-nitrogen-doped mesoporous carbon being a carrier, the active component is Pd-M. A one-step synthesis method is adopted to prepare a nitrogen-doped mesoporous carbon catalyst, an impregnation method can be adopted to synthesize the Pd-M/NOMC catalyst, and hydrogen, formic acid-sodium formate, methyl alcohol and the like are adopted as hydrogen sources for hydrodechlorination of chlorophenol. Nitrogen atoms are doped on a mesoporouscarbon material, the reactive site of catalysis is increased, and the activity of the catalyst is improved. The one-step method for synthesis is adopted, the nitrogen sources can be controlled from the source, the content of added nitrogen is easier to control, and the formed mesoporous structure is not easily damaged; by introducing nitrogen, the lowest binding energy position of palladium is migrated, electrons in nitrogen are migrated to the surface of palladium atoms, which improves the stability between palladium and the material.

The invention discloses a ternary carbon loaded palladium tin platinum nanoparticle catalyst and a preparation method thereof. The preparation method includes: dissolving a palladium-containing metal salt and a tin-containing metal salt in ethylene glycol, with the palladium and the tin being in an atom ratio of 1:1, adding a platinum metal salt, with the platinum atom and the palladium atom or the tin atom being in a ratio of 0.001:1-0.8:1, finally adding nanoscale carbon powder as a carrier of metal nanoparticles, conducting ultrasonic dispersion to obtain a uniform mixed solution, and then adding a sodium borohydride solution into the mixed solution in a dropwise manner, thus obtaining the highly dispersed ternary carbon loaded palladium tin platinum nanoparticle catalyst. In the invention, ethylene glycol is adopted as the solvent due to its high viscosity, so that the metal ion reduction and precipitation process can be more uniform, and palladium tin platinum nanoparticles with better dispersibility can be generated. The ternary palladium tin platinum nanoparticles prepared in the invention have a particle size of 2-5nm, and electrochemical tests show that the nanoparticles present obvious activity in electrocatalytic oxidation of ethanol and formic acid. The method provided in the invention is simple, and is suitable for large-scale preparation of anode catalyst materials for direct ethanol and formic acid fuel cells.

The embodiment of the invention discloses a preparation method of palladium nano crystals, comprising the following steps: adding potassium iodide solution in cetyl trimethylammonium bromide water solution to obtain mixed solution; adding palladouschloride acid solution, palladium nano cubic seed solution and ascorbic acid solution respectively into the mixed solution, and reacting fully; and crystallizing out palladium nano crystals from solution after reaction. cetyl trimethylammonium bromide severs as a surfactant, can stabilize and prevent nano crystals from precipitation, and plays a role in promoting the nano crystals to form uniform and neat shape. Ascorbic acid servers as a reducing agent in the reaction process to reduce bivalent palladium in palladouschloride acid solution into nulvalent palladium atom. Potassium iodide can absorb on the surface of the palladium nano crystals so as to influence the shape of the nano crystals. The preparation method in the invention can synthesize nano crystals in a controllable manner to form palladium nano crystals with various shapes, and is favor of researching the relationship between the shape of the palladium nano crystals and growth conditions thereof.

A palladium-silver bimetallic composite material is provided. The composite material includes silver nanometer crystals and a palladium-silver alloy layer on the surface of the silver nanometer crystals. The invention also provides a preparing method of the composite material. The preparing method includes mixing the silver nanometer crystals, a reductant, an etching agent, a surface protectant, a solvent and a palladium source compound, and then reacting the mixture to obtain the composite material. The nanometer crystals having a core shell structure are prepared by a provided synthetic method. Dispersed palladium atoms grow on the surfaces of the silver nanometer crystals, thus effectively weakening strength of palladium-hydrogen bonds and facilitating hydrogen desorption. In addition, low-cost silver nanometer particles are adopted inside the composite material, and palladium active points are distributed on the surfaces of the silver nanometer crystals, and therefore the activity of the composite material as a catalyst is high and the cost is low.

The invention discloses a CuPd metal nano catalyst of a four-feet structure, and a preparation method of the CuPd metal nano catalyst, and also discloses a CuPd/C metal nano catalyst, a preparation method of the CuPd/C metal nano catalyst, and applications of the CuPd/C metal nano catalyst in fuel battery cathodic oxygen reduction. According to the CuPd/C metal nano catalyst, the surface of carbon black is loaded with the CuPd metal nano catalyst. According to the CuPd metal nano catalyst of a four-feet structure, electrons on copper atoms are transferred onto palladium atoms, and the electrons are gathered on the tips of the four-feet structure, so that electron density of tip palladium atoms is increased further, d band center of palladium atoms is reduced, the strong adsorption between palladium atoms and oxygen is reduced, and catalytic activity is increased.

The invention provides a preparation method of a palladium diselenide two-dimensional crystalline state film layer. The preparation method comprises the following steps that 100, a base with silicon carbide as a base body and a graphene layer manufactured on the surface is prepared; 200, the temperature of the base is kept within the growth temperature range of selenium and palladium; and 300, selenium atoms and palladium atoms are generated from pure selenium and pure palladium in an evaporation way according to the reaction ratio and deposited on the base, and the selenium atoms and the palladium atoms are reacted on the base to form the two-dimensional ordered crystalline state film layer composed of the atoms, wherein in the film layer, the selenium atoms and the palladium atoms are distributed in a selenium-palladium-selenium overlaid state. By means of the method, the current situation that only palladium diselenide blocks can be obtained in the prior art is solved, the atomic-scale palladium diselenide film layer can be obtained, and convenience is brought to research on physical properties of palladium diselenide and relevant devices by sufficiently utilizing palladium diselenide.

The invention relates to a preparation method for a gold nanoring. The preparation method comprises the following steps: dissolving a palladium nano sheet, ascorbic acid and a dispersing agent into a solvent, wherein in the palladium nano sheet, the concentration of palladium atoms in a solution is 2.0*10<-4>-1.4*10<-3>mol/L, and the concentration of the ascorbic acid in the solution is 0.1-0.5mol/L; and then, injecting a chloroauric acid aqueous solution into the solution, and reacting at a temperature of 0-35 DEG C to obtain the gold nanoring, wherein a molar ratio of the ascorbic acid to the palladium atoms in the palladium nano sheet is 7:1 to 25:1. The preparation method is simple, is high in repeatability and is low in cost; and the prepared gold nanoring has a hollow structure, is uniform in dimension and is good in dispersion, and is adjustable in dimension and wall thickness.

A method for improving drastically both the selectivity and yield of hydrogen peroxide in the direct oxidation of hydrogen to hydrogen peroxide over a solid catalyst comprising palladium, which comprises: i) depositing on the solid catalyst at least two halogen containing compounds, one compound essentially comprising bromine and second compound essentially comprising fluorine with the bromine to palladium and fluorine to palladium atom ratios in the range from 0.02 to 20 and from 0.01 to 50, respectively; ii) decomposing the halo compounds deposited on the solid catalyst by calcination at a temperature above 200° C. under inert, reducing or oxidizing gas atmosphere or under vacuum; and

• • iii) contacting the solid catalyst obtained from step (ii) with a gas mixture consisting of hydrogen and oxygen or air or O₂ enriched air in an aqueous reaction medium, comprising a mineral acid at the following reaction conditions: concentration of mineral acid in the reaction medium above 0.001 mol/dm³, concentration of the solid catalyst in the reaction medium above 0.01 g/dm³, H₂/O₂ mole ratio in the gas mixture in the range from 0.01 to 10, flow rate of the gas mixture in the range from 50 cm³/g catalyst/h to 50,000 cm³/g catalyst/h, gas pressure at least 0.9 atm, and temperature below 100° C. and contact period of the reaction medium at least 0.01 h, is disclosed.

Provided is an efficient method for producing 1-chloro-2,3,3,3-tetrafluoropropene by reducing 1,1-dichloro-2,3,3,3-tetrafluoropropene, the method generating fewer by-products such as 1,1,1-trifluoropropane and 3,3,3-trifluoropropene that are products of over-reduction. The method for producing 1-chloro-2,3,3,3-tetrafluoropropene is characterized by obtaining 1-chloro-2,3,3,3-tetrafluoropropene byreacting, in a vapor phase, 1,1-dichloro-2,3,3,3-tetrafluoropropene with hydrogen in the presence of a palladium catalyst-supporting carrier that is obtained by having a carrier support a palladium catalyst that comprises chlorine and a metal containing palladium so that the ratio of the number of moles of chlorine atoms to the number of moles of palladium atoms, namely (Cl/Pd), is 2.0 or more.

The invention discloses a preparation method of a nickel-plated fiber grating sensor. The method comprises the following steps: first of all, performing surface roughening treatment on a fiber grating, then performing impregnation processing by use of a colloid palladium solution, and then immersing the fiber grating into a dispergation solution to obtain a fiber containing palladium atoms; and immersing the fiber containing the palladium atoms into a plating liquid, plating a layer of metal on the fiber containing the palladium atoms by use of an oxidation reduction reaction to obtain an initially plated fiber, immersing the initially plated fiber into an electroplate solution for electroplating to obtain a metallic nickel galvanized coating, and finally, welding the electroplated fiber grating on a sensor substrate by use of laser to obtain a nickel-plated fiber grating sensor. Compared to the prior art, the method provided by the invention has the following advantages: the metallization of the fiber grating is realized, the fiber grating can be welded on the sensor substrate through a welding mode, relative movement between a fiber core layer and a fiber coating can be prevented, measuring data can truly reflect the stress and strain of an object to be measured, and the sensor accuracy is improved.

The invention provides a preparation method of a palladium-charcoal catalyst and further provides the palladium-charcoal catalyst prepared by using the preparation method and application of the palladium-charcoal catalyst. Compared with the prior art, palladium ions which are already adsorbed to a carrier are subjected to in-situ reduction through electrochemical in-situ reduction; compared with aconventional method that a reducing agent is added or electrochemical deposition is implemented, the preparation method is rapid in reduction speed, and the metal palladium takes the shape of sheetsand has a large contact area with the carrier, so that migration and dropping of the palladium metal can be well prevented, and the catalyst is high in stability, high in palladium atom utilization rate and good in catalysis performance; and meanwhile, a high conversion rate and yield can be achieved without adding other metals into the catalyst, and problems of separation and palladium metal recycling caused by conventional preparation methods can be solved.

The invention discloses a platinum nanocage immune probe and a preparation method thereof and an application thereof in preparing electrochemical immunosensor. According to the invention, cubic platinum nanocage-shaped particles are obtained by substituting platinum atoms for palladium atoms in palladium nano cubic particles. The beneficial effects of the invention are: the method is simple; the obtained platinum nanocage-shaped particles are cubic in shape and have uniform sizes. Experimental results prove that, a cubic nanocage structure has a better catalysis effect than a globular platinum particle does so that the former has a more obvious signal amplification effect. An electrochemical immunosensor prepared by the immune probe which is prepared by platinum nanocage-shaped particles has strong and stable signals and good repeatability; simultaneous detection of double target is realized through marking electric signal material which can be distinguished by peak potential. The platinum nanocage immune probe provided in the invention and electrochemical immunosensors prepared with the same have a large application prospect in the field of immunosense.

The invention provides a high-dispersion single-atom Pd/mesoporous Al2O3 catalyst, and a preparation method and application thereof. According to the invention, mesoporous Al2O3 with more surface defects is synthesized in situ, and palladium atoms are stably loaded on the mesoporous Al2O3 with more defect sites by an atomic lamination technology, so that anchoring with the maximum number of the palladium atoms with unsaturated penta-coordinated Al<3+> in mesopores can be effectively realized, and therefore, the single-atom Pd catalyst with a higher dispersion degree can be prepared. Atomic efficiency can be effectively improved, noble metal can be utilized to the maximum extent, and cost of the catalyst can be reduced. Moreover, the high-dispersion single-atom Pd/mesoporous Al2O3 catalystcan maintain high acetylene selectivity in an acetylene selective hydrogenation process, and ethylene selectivity can be greatly improved.

The present invention provides novel high-valent palladium complexes. The complexes typically include multi-dentate ligands that stabilize the octahedral coordination sphere of the palladium(IV) atom. These complexes are useful in fluorinating organic compounds and preparing high-valent palladium fluoride complexes. The invention is particularly useful for fluorinating compounds with ¹⁹F for PET imaging.

The invention provides a palladium-doped carbon film material with photovoltaic effect. A film with the thickness of 20-200nm is sputtered on a 0.5-1.0mm mono-crystalline silicon wafer to manufacture a palladium-doped carbon film/silicon dioxide/silicon material or palladium-doped carbon film/silicon heterogenous junction material, wherein the film with the thickness of 20-200nm is a carbon film with the doped palladium atom content of 0-5%. The material has photovoltaic effect, and can be used for manufacturing solar cells and photosensitive devices; and the manufactured solar cells have higher conversion efficiency, and have simple manufacture process and high finished product ratio.

The invention discloses a magnetic nano-carbon nitride photocatalyst capable of removing algae and a preparation method thereof. The photocatalyst takes graphite-phase carbon nitride as a carrier to load noble metal palladium Pd, so the photocatalytic activity of the photocatalyst is improved. The precious metal palladium Pd improves the separation efficiency of photo-generated charge carriers of the semiconductor photocatalyst by capturing electrons, and the surface plasmon resonance (SPR) effect of palladium atoms can greatly improve the visible light absorption rate of the photocatalyst, accelerate the generation of free radicals and promote the growth of photocatalytic oxidation algae. Meanwhile, nano-Fe3O4 is loaded in the photocatalyst provided by the invention, so the photocatalyst has good magnetism, and recovery is completed through a magnetic attraction effect. Therefore, the development of the photocatalyst has important significance on the removal work of harmful algae.