12 results about "Transition metal nanoparticles" patented technology

The invention discloses a magnesium-based solid hydrogen storage material as well as a preparation method and application thereof, and relates to the technical field of solid hydrogen storage materials. The magnesium-based solid hydrogen storage material comprises a magnesium-based alloy and a composite catalyst, and the magnesium-based alloy comprises the following chemical components in percentage by mass: 1.0-10.0% of nickel, 1.0-5.0% of aluminum and the balance of magnesium; the composite catalyst is transition metal nanoparticles loaded on a carbon nanomaterial; the mass percent of the composite catalyst in the magnesium-based solid hydrogen storage material is 1%-20%. Through the synergistic effect of all the components, the material shows excellent hydrogen absorption kinetics at a low temperature of 250 DEG C, can absorb more than 6.0 wt% of hydrogen within 10 minutes, and can obviously reduce dehydrogenation activation energy to about 75 kJ / mol, so that the low-temperature kinetics performance and cycling stability of the material are comprehensively improved; the technical problem that a traditional magnesium-based material is difficult to consider high capacity, rapid dynamics and long service life at the same time is solved.

The present invention relates to nucleic acid-adsorbing materials and the applications thereof. The nucleic acid-adsorbing materials comprise transition metal nanoparticles coated with one or more modulators, and may further comprise a sensing carrier to form a nanocomposite. The nucleic acid-adsorbing materials can adsorb short or small polynucleotide fragments in a sample solution, which leads to a change in the absorption spectrum and can be detected, quantitated, or characterized with a spectrophotometer.

This invention discloses a two-dimensional layered ammonia oxidation catalyst based on MXene, its preparation method, and its application in low-temperature ammonia fuel cells. The catalyst comprises an active component and a support. The active component is one or two of the transition metals Pt, Ir, and Pd, and the support is accordion-shaped MXenes. The catalyst support prepared by this invention has a large specific surface area, in which the transition metal nanoparticles are uniformly dispersed and have strong interactions with the MXenes, which can significantly improve its ammonia electrocatalytic oxidation activity, showing good application prospects in ammonia fuel cells.

Provided is a method for producing a transition metal nanoparticle support, the method including the steps of: (I) obtaining a mixture by mixing a polymeric organic compound, an oxide of at least one transition metal or a hydroxide of at least one transition metal, and an oxide or hydroxide of at least one element selected from alkali metals, alkaline earth metals, aluminum, and lanthanoids; (II) obtaining a solid residue by heating the mixture; and (III) obtaining, from the solid residue, a support in which nanoparticles of the transition metal are supported.

This invention belongs to the field of electrochemical energy storage materials and devices, specifically relating to an artificial interface layer for lithium anodes, its preparation method, and its application. The artificial interface layer for lithium anodes provided by this invention comprises a composite of transition metal nanoparticles and carbon, and a fluoropolymer. It solves the problem in existing technologies where the use of low-ionic-conductivity organic binders in artificial SEI layers leads to slow lithium-ion transport kinetics at the interface, making it difficult to balance high mechanical strength and rapid ion transport. This results in an artificial interface layer with excellent rate performance and cycle stability.

The application provides a carbon-based transition metal nanoparticle and single-atom synergistic electrocatalyst, a preparation method, application and a zinc-air battery, and belongs to the technical field of electrocatalysis and metal-air batteries. In the application, through the competitive anchoring and limited action of a nitrogen-containing metal chelating agent and a nitrogen-rich precursor on metal atoms in a pyrolysis process, in-situ construction and stable coexistence of transition metal nanoparticles and single atoms are realized in one step, a single-atom-nanoparticle synergistic structure is formed, the single-atom sites dominate the efficient oxygen reduction reaction, and the nanoparticle sites dominate the efficient oxygen evolution reaction. The method has the advantages of simple process, good repeatability, easy scaling from a kilogram to a kilogram, and consistent catalyst structure performance after scaling. The membrane electrode and the zinc-air battery based on the catalyst show excellent bifunctional catalytic activity, high power density and long cycle stability, and provide a complete technical solution from materials to devices for the commercialization of high-performance and low-cost zinc-air batteries.

The present invention provides an electrode catalyst which has high catalytic activity while maintaining good durability, substance conductivity, and electrical conductivity, and which can be manufactured at a low cost.　The present invention provides an electrode catalyst which is composed of a void-containing body having voids, wherein: the void-containing body is provided with a core part and a skin layer that covers the core part; the core part is composed of a metal; the skin layer is composed of Ni and an oxide that contains a second metal; the second metal is a metal that is different from Ni; in addition, the skin layer is loaded with transition metal nanoparticles that are dispersed on the surface of the skin layer; and the particle diameter of the transition metal nanoparticles is smaller than the particle diameter of the metal and the particle diameter of the oxide.

The invention discloses a transition metal nanoparticle embedded biomass-derived nitrogen-doped carbon electrocatalyst as well as a preparation method and application thereof, and belongs to the technical field of H2O2 preparation. The problems that a transition metal-carbon material catalyst is low in H2O2 selectivity, complex in preparation process and not environmentally friendly are solved. The preparation method of the electrocatalyst comprises the following steps: carrying out a hydrothermal reaction on a biomass fiber material and concentrated alkali liquor, then carrying out a hydrothermal reaction on obtained biomass cellulose, transition metal salt and an organic ligand to obtain a metal-loaded nitrogen-containing biomass carbon material, and carrying out heat treatment on the biomass carbon material to obtain the electrocatalyst. The electrocatalyst is used as a cathode to electrocatalyze two-electron oxygen reduction to synthesize H2O2. According to the invention, a nitrogen source easy to pyrolyze and oxidized fibers are coordinated and combined through hydro-thermal synthesis, and holes are etched and formed in the catalyst during high-temperature pyrolysis, so that the mesoporous content of the catalyst is increased; the catalyst has good ability of two-electron oxygen reduction electrosynthesis of H2O2, and the H2O2 selectivity and yield are high.

The invention discloses a hydrogen storage hollow glass microsphere, a preparation method thereof and a hydrogen charging and discharging method. The hydrogen storage hollow glass microspheres are composed of borosilicate glass ball walls and hollow cavities wrapped by the ball walls, transition metal nanoparticles are dispersed in the borosilicate glass ball walls, and the transition metal nanoparticles are products obtained by reducing transition metal oxide nanoparticles through hydrogen. The preparation method comprises the steps of preparation of uniform glass frits, preparation of primary hollow glass microspheres, preparation of hydrogen storage hollow glass microspheres and the like. The hydrogen charging and discharging method comprises the two steps of hydrogen charging of the hydrogen storage hollow glass microspheres and hydrogen discharging of the hydrogen storage hollow glass microspheres. Under the catalytic action of the transition metal nanoparticles, the hydrogen adsorption free energy is reduced, the permeation and diffusion rate of hydrogen is increased, the hydrogen permeation coefficient of the hydrogen storage hollow glass microspheres at the low temperature of 100-200 DEG C is increased, the operation temperature of hydrogen charging and discharging is reduced, and the energy consumption is reduced.

The application belongs to the technical field of catalytic materials, and particularly relates to a porous catalytic material based on hyperbranched polyamide-amine and application thereof in biomass hydrodeoxygenation reaction. The porous catalytic material based on hyperbranched polyamide-amine is prepared by using maleic anhydride modified hyperbranched polyamide-amine as a carrier, loading transition metal nanoparticles on the carrier, and then performing cross-linking reaction between the carrier and a silicone prepolymer. The porous catalytic material based on hyperbranched polyamide-amine has a hierarchical pore structure, a high specific surface area, excellent mechanical strength and outstanding thermal stability. The cavity structure of the maleic anhydride modified hyperbranched polyamide-amine can effectively inhibit the agglomeration of transition metal nanoparticles at high temperatures. The silicone cross-linking network endows the porous catalytic material based on hyperbranched polyamide-amine with structural stability at high temperatures, so that the porous catalytic material based on hyperbranched polyamide-amine can exhibit high activity, high selectivity and excellent cycle stability in biomass hydrodeoxygenation reaction.

The invention belongs to the technical field of new materials, and particularly relates to preparation and doping modification of rare earth oxide loaded transition metal nanoparticles for low-pressure ammonia synthesis. The supported synthetic ammonia catalyst provided by the invention comprises a cerium dioxide carrier (CeO2) with characteristic morphology and rich oxygen vacancies, a lanthanum-doped and modified cerium dioxide carrier (La-CeO2), and a metal nano-material which is supported on a rare earth metal oxide carrier and is generated through high-temperature gas phase reduction, the preparation method comprises the following steps: dissolving rare earth metal nitrate and an organic ligand in N-N dimethylformamide, then adding an initiator and a stabilizer, putting an obtained mixed solution into a hydrothermal kettle, and carrying out solvothermal reaction at high temperature; the preparation method comprises the following steps: centrifuging, washing, drying and calcining a metal organic framework precursor obtained by solvothermal reaction to prepare a rare earth metal oxide carrier, and loading transition metal chloride on the rare earth metal oxide carrier by taking acetone as a solvent through a rotary evaporation method; and performing high-temperature treatment in a reducing atmosphere to obtain the transition metal nanoparticle loaded rare earth metal oxide ammonia synthesis catalyst. The supported ammonia synthesis catalyst has very strong nitrogen activation capability and very high low-pressure ammonia synthesis performance.

A catalyst comprising transition metal nanoparticles, stabilizing ligands, and a support material, wherein at least a portion of the stabilizing ligands are adsorbed on the surface of the transition metal nanoparticles such as to form stabilized transition metal nanoparticles, wherein the stabilized transition metal nanoparticles are supported on the support material, wherein the catalyst displays a molar ratio of the stabilizing ligands to the transition metal in the nanoparticles calculated as the element, wherein the molar ratio is comprised in the range of from 0.1 to 25.