103results about How to "Increased oxygen reduction activity" patented technology

The invention relates to a composite material of a nitrogen-doped porous carbon-wrapped carbon nano tube as well as a preparation method and an application of the composite material. The preparation method comprises the following steps: dispersing the carbon nano tube in water, adding a carbon source to obtain a reaction system, subsequently performing hydrothermal reaction, performing thermal treatment on the carbon nano tube wrapped with a carbon layer on the surface, and a nitrogen source at the high temperature so as to obtain the composite material of the nitrogen-doped porous carbon-wrapped carbon nano tube. According to the preparation method, the carbon source is polymerized under a hydrothermal reaction condition so as to obtain the carbon layer, the outer surface of the carbon nano tube is wrapped with the carbon layer, subsequently the carbon layer is carbonized and decomposed to generate a porous structure under high temperature treatment, and at the same time, the gasified nitrogen source is diffused to the carbon layer through ducts to be subjected to in-situ doping. The composite material provided by the invention can be used as a cathode oxidation reduction catalyst of a fuel battery, is excellent in catalysis, and is high in oxidation activity when being compared with other nitrogen-doped materials reported in documents. The preparation method provided by the invention is simple and economic in process, convenient to operate and easy to achieve the large-scale production.

The invention provides a preparation method of an iron, cobalt and nitrogen co-doped hierarchical pore carbon nanosheet oxygen reduction catalyst. According to the method, a ZnO nanosheet is taken asa template and a zinc source, 2-methylimidazole is taken as organic ligand, iron acetylacetonate is taken as an iron source, cobalt salt is taken as a cobalt source, and a core-shell structure ZnO@Zn / Fe / Co-ZIF precursor taking the ZnO nanosheet as a core and trimetallic hybrid zeolitic imidazolate skeleton compound Zn / Fe / Co-ZIF as a shell is obtained through the regulation of the ratio of the cobalt source to the iron source and adoption of a solvothermal method. ZnO@Zn / Fe / Co-ZIF is subjected to high-temperature calcinations in inert atmosphere, and the iron, cobalt and nitrogen co-doped hierarchical pore carbon nanosheet oxygen reduction catalyst is directly obtained. The method has the advantages that acid pickling is not required to remove a core layer template, an obtained carbon nanosheet is high in specific surface area, has a hierarchical pore structure, is rich in catalytic activity sites, and shows higher oxygen reduction catalytic activity than that of an iron and nitrogen doped carbon nanosheet and a cobalt and nitrogen doped carbon nanosheet.

The invention discloses a Ce-Zr bimetal cluster MOF-based oxygen reduction electrocatalyst and a preparation method and application thereof, and belongs to the field of proton exchange membrane fuel cell catalysts. The preparation method comprises the following steps: dispersing a metal salt in a solvent, adding an organic acid and a macrocyclic compound, carrying out ultrasonic treatment at 20-40DEG C for 10-30 min, carrying out a reaction at 120-150 DEG C for 6-12 h, carrying out suction filtration, washing until the filtrate is colorless, performing drying, and carrying out high-temperature pyrolysis carbonization to obtain the bimetallic cluster MOF-based electrocatalyst. The preparation method is simple to operate, easy to control and environment-friendly, and the prepared bimetalliccluster MOF-based electrocatalyst has very high oxygen reduction activity and can be used for proton exchange membrane fuel cells.

The invention provides a method for stabilizing a palladium catalyst by montmorillonite and belongs to the technical field of fuel cells. The method comprises the following steps of: exchanging palladium cations into a montmorillonite layer intercalated with perfluorinated sulfonic acid resin through ion exchange; performing in-situ reduction on the palladium cations into nano palladium inside the montmorillonite layer by using a chemical method; and finally, forming the catalyst with an excellent three-phase interface of a fuel cell catalyst by introducing carbon powder. The prepared catalyst has the advantages of high catalytic stability and high oxygen reduction activity, can be widely used as a catalyst of a proton exchange membrane fuel cell taking hydrogen and methanol as fuel, has better oxygen reduction catalytic performance than a Pd / C catalyst using carbon as a carrier, is equivalent to a commercial Pd / C catalyst in British Jonhson-Matthey Company, has obviously higher stability than that the Pd / C catalyst using carbon as the carrier, and can replace the Pd / C catalyst to become a main fuel cell catalyst.

The invention provides a method for one-step hydrothermal synthesis preparation of a composite anode material of a solid oxide fuel cell. The composite anode material synthesized according to the method belongs to a hybrid ion-electron conductor and is simultaneously provided with spinel electron conduction phase and a cubic fluorite ionic conduction phase, powder particle is relatively small in size and is uniformly distributed, the composite anode material has high dispersibility, high-temperature processing is not needed during the synthesis process, powder is prevented from being agglomerated during calcination, and the composite anode material is relatively high in reaction activity and can stably run in a low-temperature condition when applied to a single battery.

The invention discloses a method for solid-phase macrosynthesis of non-noble metal oxygen reduction catalyst, and a catalyst and application thereof. The preparation method comprises the following steps of: (1) uniformly mixing a chelating agent with an inorganic metal salt, and performing solid-phase grinding to obtain a precursor; and (2) performing heat treatment on the precursor obtained in the step (1) in an inert atmosphere, and washing, separating and drying the product to obtain the non-noble metal oxygen reduction catalyst. The method for solid-phase macrosynthesis of a non-noble metal oxygen reduction catalyst disclosed by the invention is simple in process and suitable for large-scale industrial production, and the obtained non-noble metal oxygen reduction catalyst is excellentin performance and has the potential to be used as a substitute of a noble metal oxygen reduction catalyst of a fuel cell or a metal-air cell.

The invention provides preparation and application for a non-noble metal electro-catalyst with a core-shell structure, and belongs to the field of fuel cells and metal / air cell catalysts. The preparation for the non-noble metal electro-catalyst comprises the steps of dispersing carbon black into an HNO3 solution, performing back flow at a temperature of 20-90 DEG C for 0.5-10h, performing suction filtration, washing until the solution is neutral, and drying; dissolving porphyry into organic solvent, adding pre-processed carbon black, performing ultrasonic dispersion for more than 20 min, and drying the solvent by evaporation; roasting the rest materials in carrier gas at a temperature of 400-1,200 DEG C for 0.5-4h, cooling to room temperature, and adding an acidic water solution, and performing back flow in a water bath at a temperature of 30-90 DEG C for 1-24h, and then performing suction filtration, washing by deionized water until the solution is neutral, and drying to obtain the non-noble metal electro-catalyst with the core-shell structure. The preparation is simple in operation, easy to control, mild in conditions and environment-friendly; and the prepared non-noble metal electro-catalyst with the core-shell structure is quite high in oxygen reduction activity, and can be used for the fuel cells and the metal / air cells.

The invention discloses a preparation method of an auto-doped carbon catalysis material based on activated sludge domestication. The preparation method includes the following steps that 1, nitrifying domestication or phenol domestication is conducted on activated sludge to obtain domesticated activated sludge; 2, the obtained sludge in the step 1 is dried, grinded and screened, is calcinated at the temperature of 700-1000 DEG C under an inert gas atmosphere for 1.5-4 hours, the sludge is subjected to acid treatment, then is washed with distilled water to be neutral and is dried and screened at the temperature of 55-105 DEG C to obtain auto-doped carbon catalysis material powder. The preparation method is simple, the costs are low, raw material sources are wide, the nitrogen element content in the catalysis material is increased, and the catalysis material has the good catalytic performance of oxygen reduction.

This invention provides a macrocyclic-organic-compound-based catalyst for reducing oxygen having high oxygen-reducing activity. This oxygen-reducing catalyst comprises a conductive support and, supported thereon, a porphyrin complex represented by formula (I): wherein Rs each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a halogen atom, an amino group, a hydroxyl group, a nitro group, a phenyl group, or a cyano group or adjacent Rs together form a methylene chain having 2 to 6 carbon atoms or aromatic ring; R's each independently represent a thienyl group; and M represents a metal atom selected from the group consisting of Cu, Zn, Fe, Co, Ni, Ru, Pb, Rh, Pd, Pt, Mn, Sn, Au, Mg, Cd, Al, In, Ge, Cr, and Ti, provided that M may bind to a halogen atom, an oxygen atom, -OH, a nitrogen atom, NO, or -CO.