131results about How to "Improving Oxygen Reduction Catalytic Performance" patented technology

The invention relates to preparation methods of porous carbon from towel gourd vegetable sponge and a composite material of the porous carbon and application of the porous carbon and the composite material in supercapacitor electrode materials. The method for preparing the porous carbon comprises the following steps: (1) washing the towel gourd vegetable sponge, and performing carbonization heat treatment in an atmosphere containing NH3 at a proper temperature; (2) mixing the carbonized product and KOH in a proper proportion, and activating in N2 at the temperature of 750 DEG C. The inner diameter of pore passages of the prepared porous carbon is between 1mu m and 15mu m, the pore wall thickness is between 0.3mu m and 1mu m, and the activated specific surface area can be 1510m<2>/g. The method for preparing the composite material comprises the following steps: reacting the porous carbon with a KMnO4 solution, and growing MnO2 nanosheets, thereby obtaining a porous carbon/MnO2 composite material; or reacting the porous carbon with aniline to obtain a porous carbon/aniline composite material. When serving as the supercapacitor electrode materials, the prepared porous carbon and the composite material thereof have more excellent performance and favorable application prospect compared with a conventional carbon material.

The invention provides a method for an anchoring platinum catalyst of a transition metal on a carbon nanotube, which pertains to the technical field of fuel cells. The method purifies the carbon nanotube sold on a market by concentrated nitric acid and uses mixed acid of hydrogen peroxide and the concentrated nitric acid for treatment to obtain the functionalized carbon nanotube. And then the functionalized carbon nanotube, partial platinum salt and all transition metal M salt are stirred and reflow for certain time, added with rest platinum salt to continue to reflow, cooled, washed centrifugally, dried and carried out heating treatment in a hydrogen atmosphere, thus obtaining the anchoring platinum catalyst of the transition metal on the carbon nanotube. The anchoring platinum catalyst of the transition metal on the carbon nanotube prepared by the invention has extremely good stability and the catalytic activation of oxygen reduction and can substitute kindred commercialized catalysts.

The invention discloses a preparation method of a carbon supported cobalt phthalocyanine (CoPc/C) catalytic material and aims at providing a preparation method of a catalytic material with simple and stable technology, low cost and easy industrialized production. The method comprises the following steps: placing phthalic anhydride, urea, CoCl2.6H2O, ammonium molybdate and carbon black powder processed by acid or H2O2 in a mortar to fully grind, heating the mixture to 200-900 DEG C, and keeping temperature for 3h to obtain the CoPc/C catalytic material, wherein the metal content of the material is 2.5-8wt%. The preparation method of the invention uses preprocessed carbon black as carrier, phthalic anhydride, urea and CoCl2.6H2O as raw materials and ammonium molybdate as catalytic material to directly add the carbon black material processed by acid in the reactant system for high-temperature pyrolysis and obtain the CoPc/C material in one step. The preparation method is simple, the cost is low, the production efficiency is high and the industrial production of the material is easy to realize.

The invention belongs to the technical field of micro devices, and particularly relates to a core shell structure composite fiber based on a carbon nano tube and a preparation method and application thereof. In the invention, the flexible composite fiber material with a core shell structure is obtained by in-situ growing of a netlike nitrogen-doped carbon nano tube on the surface of an oriented carbon nano tube; and the composite fiber shows excellent oxygen reduction performance by combining perfect three-dimensional jump electrical conductivity of the carbon nano tube and good electrocatalysis performance of the nitrogen-doped carbon nano tube. The current density of oxygen reduction of a micro electrode made from the composite fiber material is 5 times that of a platinum wire electrodeunder the same conditions. The carbon nano tube composite fiber electrode also has a remarkably high sensitivity (up to 1.0 muAmM<-1>) to the trace detection of H2O2. Moreover, the composite fiber has low preparation cost and high efficiency, can be industrially amplified more easily to solve problems in practical application, and has a wide application prospect when being used as a novel electrode material widely applied to photoelectric devices.

The invention discloses an exotic-atom-doped graphene, and a preparation method and application thereof, belonging to high-performance chemical power sources and correlated fields. The preparation method comprises the following steps: dissolving an exotic atom precursor compound in a solvent, and uniformly mixing; removing the solvent to obtain solid powder; and treating the solid powder at 700-1000 DEG C in an inert atmosphere for 1-5 hours to prepare the exotic-atom-doped graphene in situ. The exotic-atom-doped graphene has comparable oxygen reduction catalytic activity with the commercialized Pt/C, has better methanol oxidation resistance and stability than the commercialized Pt/C catalyst, and can be used in the field of fuel cells. The exotic-atom-doped graphene has double-function catalytic properties, can obtain high charge/discharge capacity, excellent charge/discharge magnification and long cycle life when being used for secondary lithium-air cells, and is applicable to the field of metal-air cells.

The invention discloses a preparation method of a three-dimensional graphene/porphyrin compounded oxygen reduction electrocatalyst. The preparation method comprises the following step of: (1) performing thermal treatment on three-dimensional grapheme at 300-800 DEG C for 30-90 min; and (2) agitating and mixing the thermally treated three-dimensional grapheme with the porphyrin under a liquid phase condition, performing centrifugal cleaning after reaction, and drying the product in vacuum to obtain three-dimensional graphene/porphyrin compounded oxygen reduction electrocatalyst. The three-dimensional graphene is thermally treated so as to obviously improve the oxygen reduction catalytic performance of the three-dimensional grapheme, and then the thermally treated three-dimensional grapheme is compounded with the porphyrin to prepare the graphene/porphyrin compounded catalyst. The compounded catalyst is better in oxygen reduction catalytic performance, long-term stability and obvious in anti-methanol catalyst performance, low in cost, stable in performance, and simple in preparation method, can be used as oxygen reduction electrocatalysts of commercial fuel batteries by replacing precious metal platinum.

The invention provides a preparation method for silver-loaded N-doped graphene. The preparation method comprises the following step: mixing functionalized graphene, silver nitrate and ammonium hydroxide and reacting to obtain the silver-loaded N-doped graphene. The preparation process is easy and liable to implement, energy is saved, environment friendliness is realized, and the silver-loaded N-doped graphene has a relatively good oxygen reduction catalytic performance.

The invention discloses a BaCoO3-delta base B-position Bi2O3-Nb2O5 co-doped cathode material of solid oxide fuel cell, a preparation method and applications thereof. The provided cathode material has a perovskite type structure and is represented by a chemical formula: BaBi<x>Nb<y>Co<1-x-y>O<3-delta>, wherein the delta represents oxygen excess or oxygen deficiency (-1=<delta=<1), the x represents the doping amount of Bi2O3 (0=<x=<0.15), and the y represents the doping amount of Nb2O5 (0=<y=<0.2). The chemical compatibility between the provided BaBi<x>Nb<y>Co<1-x-y>O<3-delta> cathode material and the conventional electrolyte material such as GDC, and the like is good. In the air the current can be well conducted by the oxygen ions and electrons. In the temperature range of 450 to 850 DEG C, the provided cathode material has a very good oxidation-reduction catalytic activity. The cathode material is suitable for a solid oxide fuel cell used at a mid-low temperature.

The invention discloses a nitrogen-sulfur double-doped non-metallic carbon-based oxygen reduction catalyst with grading holes and preparation and belongs to the technical field of catalysts. An organic polymer with nitrogen, sulfur and carbon in uniform distribution is synthesized through a simple method, the organic polymer is further subject to high-temperature calcination, a carbonization process, a nitrogenization process and a sulfurization process are completed simultaneously, and then the nitrogen-sulfur double-doped grading hole carbon material is prepared. The material has a grading hole structure under the condition of not using a template, the specific surface area is large, the synthesis method is simple, the raw materials are easy to obtain, cost is low, and the material has efficient oxygen reduction reaction catalytic activity and good stability and has broad application prospects in the fields of metal-air cells, regenerative fuel cells, etc.

The invention relates to an iron-nitrogen co-doped composite material used for increasing oxygen reduction activation of a fuel cell cathode; catalytic performance and stability of the material are increased by taking 4, 5-dicarbonitrile as a ligand by adding ferric salt. The iron-nitrogen co-doped composite material disclosed by the invention has the beneficial effects that the iron-nitrogen co-doped composite material (DCI-Fe-800) is prepared by adopting a single-step solvothermal method, and the composite material shows good electro-catalytic performance when being used for oxygen reduction reaction; electrochemical performance of the material is increased by regulating and controlling morphology of the material; through addition of 4, 5-dicarbonitrile, not only are a carbon source and a nitrogen source provided, but also nitrogen of different kinds are formed after high-temperature calcination, therefore very good catalytic action is exerted; a metal-nitrogen co-doped structure is formed by addition of the ferric salt, and through synergistic action between metal and nitrogen, oxygen reduction catalytic capacity of the material is further improved.

The invention discloses a preparation method for a base metal oxygen reduction catalyst. The preparation method includes following steps: weighing a defined amount of carbon dust treated by concentrated nitric acid; adding newly steamed pyrrole, oxidizing agent (ferric chloride) and doping agent (para-toluenesulfonic acid) in the carbon dust; decompressing and filtering mixed solution after uniformly stirring; then drying in a vacuum manner for a few of hours; weighing a defined amount of cobalt salt to be mixed with the mixed solution; decompressing and evaporating after uniformly stirring; and calcinating dried powder at a high temperature so as to obtain the base metal oxygen reduction catalyst with good electrochemical performances. The cheap and environment-friendly ferric chloride is used as the oxidizing agent, the base metal catalyst with the excellent oxygen reduction performance is prepared, the maximum peak potential of an oxygen reduction process catalyzed by the catalyst reaches 0.686V, and the maximum electron transfer number reaches 3.84.

The invention relates to the technical fields of catalysts and catalyst synthesis and particularly relates to a nitrogen-doped graphene loaded Pd/Co catalyst and a preparation method thereof. The nitrogen-doped graphene loaded Pd/Co catalyst is prepared from the following raw materials in parts by weight: 100 parts of Co( NO3 )2.6H2O, 200-250 parts of nitrogen-doped graphene, 1175-1250 parts of potassium borohydride and a proper amount of 0.05mol/L PdCl2 solution, wherein the molar ratio of Pd to Co is 2 to (1-4). The nitrogen-doped graphene loaded Pd/Co catalyst has the beneficial effects that (1) by virtue of nitrogen-doped graphene, the dispersity of a Pd/Co alloy catalyst can be promoted, Pd particles are uniformly distributed on a carrier, and particle sizes are uniform; and (2) the desorption and further reaction of oxide substances can be effectively promoted, so that the oxygen reduction catalysis of the catalyst is enhanced, and the performance and stability of the catalyst are improved.

The invention discloses a catalyst prepared by in-situ growth of carbon nanotubes on ordered mesoporous carbon, and a preparation method and an application of the catalyst. The composite catalyst is prepared by performing in-situ growth of carbon nanotubes on nitrogen-doped ordered mesoporous carbon; equivalently, a triblock copolymer is used as a soft template agent, and a soluble resin is used as a carbon source; transitional metal salt is added in the preparation process; a transitional metal element is introduced in an in-situ manner; and meanwhile, active points which facilitate growth of the carbon nanotubes are generated under mixed atmosphere of ammonia gas and hydrocarbons based on the transitional metal components introduced in a modifying process of the ordered mesoporous carbon material so as to realize nitridation and growth of carbon nanotubes in one step. The composite catalyst prepared by in-situ growth of carbon nanotubes on ordered mesoporous carbon has large activity specific surface and high conductivity performance, and shows excellent oxygen reduction catalytic performance and high electrochemical stability.

The invention belongs to the technical field of nano novel material preparation and relates to an oxygen reduction catalyst for heteroatom doped carbon microsphere loaded iron phosphide nanoparticles.According to the nano catalyst, polyphosphazene microspheres are adopted as a heteroatom doped porous carbon microsphere precursor, an organic/inorganic ferric salt is adopted as an iron phosphide precursor, and the ferric salt is adsorbed by polyphosphazene microspheres to prepare the catalyst through carbonization in the presence of an inert atmosphere. The catalyst has catalytic activity approximate to that of a commercial Pt/C catalyst, is low in price and easy to obtain, and meanwhile has properties such as catalysis stability, methanol resistance, carbon monoxide toxicity resistance which are higher than those of the commercial Pt/C catalyst.

The invention relates to a method for preparing a graphene based non-metallic oxygen reduction catalyst. The graphene based non-metallic oxygen reduction catalyst is a graphene based oxygen reduction catalyst doped with non-metallic hetero-atom, the non-metallic hetero-atom comprises N, S, B and/or I, the method comprises the followings: oxidized graphene is prepared to be oxidized graphene solution with the concentration of 0.1 to 5 mg/ml; at the temperature of 70 to 120 DEG C, the oxidized graphene solution is stirred for 1 to 3 hours and then a reducing agent containing non-metallic hetero-atom is added, the temperature is kept to be 70 to 120 DEG C, stirring is performed continuously for 18 to 48 hours so as to achieve in-situ doping of the non-metallic hetero-atom during graphene reduction-oxidation; centrifugation, washing and drying are performed on the solid so as to obtain the graphene based non-metallic oxygen reduction catalyst.

The invention belongs to the technical field of preparation of new nano materials, and relates to a heteroatom-doped carbon nanotube-loaded iron phosphide nanoparticle oxygen reduction catalyst. The nanocatalyst takes polyphosphazene nanotubes as a heteroatom-doped carbon nanotube precursor and an organic iron salt or inorganic iron salt as an iron element precursor. The iron element precursor isadsorbed by the polyphosphazene nanotubes, one-step high temperature carbonization is performed in an inert atmosphere, and the heteroatom-doped carbon nanotube-loaded iron phosphide nanoparticle composite material is obtained. The composite material has excellent oxygen reduction catalytic performance, the catalytic activity of the oxygen reduction catalyst is close to that of a commercial Pt/C catalyst, and the oxygen reduction catalyst is cheaper and easier to obtain; at the same time, the catalytic durability, the methanol toxicity resistance and other characteristics are better than thoseof the commercial Pt/C catalyst.

The invention relates to a non-cobalt IT-SOFC (Intermediate-Temperature Solid Oxide Fuel Cell) stable anode material and application thereof and belongs to the technical field of fuel cells. The A site of SrFeO3-delta is doped with Nd, and the B site of the SrFeO3-delta is doped with Cu, so that the prepared (Nd1-xSrx)a (Fe1-yCuy)bO3-detal (NSCFu) anode material has high oxygen reduction catalytic activity, and the electrochemical performance is greatly improved. The anode material has long-term stability, and meanwhile has the advantages of high electronic conductivity, and high chemical compatibility and thermal expansion compatibility with cerium-oxide-based electrolytes. Thus, the SOFC anode material is potential.

The invention discloses a natural plant based preparation method for a low-cost high-efficiency catalyst for oxygen reduction reaction. The method includes the steps: 1) collecting natural plants grew in the natural world and containing hybrid elements such as nitrogen, sulfur, phosphorus, boron or selenium and drying the plants; 2) placing the dried natural plants in a high-temperature furnace, heating to 800-1600 DEG C under the protection of nitrogen at the heating rate of 1-20 DEG C/minutes and keeping the temperature for a certain time; 3) enabling the electric furnace to be cooled naturally to below 400 DEG C, and taking carbonized materials out so that the catalyst for oxygen reduction is obtained. Catalysts of the type have the oxygen reduction catalytic performances equivalent to those of 20%wtPt/c and other catalysts based on carbon nanotubes, graphene and the like and are far lower in cost than those of similar catalysts. The catalyst can be widely applied to alkaline, neutral and acidic fuel cells.

The invention relates to a method for preparing a hollow carbon nano cage through burning. The method comprises the steps of placing burning magnesium in a carbon dioxide atmosphere so that the magnesium reacts with the carbon dioxide, collecting ash obtained from burning, adding acid, stirring and reacting to remove magnesium oxide, washing and drying to obtain the hollow carbon nano cage. The method can be used for preparing the hollow carbon nano cage by taking magnesium oxide obtained by burning the magnesium in the carbon dioxide, preparing solid carbon nanoparticles on a magnesium oxide template obtained by burning carbon generated from a reaction between carbon source, i.e., carbon dioxide, and magnesium in the carbon dioxide in an in-situ attachment manner, and removing the magnesium oxide template through acid. All materials adopted in the process are environment-friendly reagents and generated magnesium salt solution can be recovered; the entire process is simple in equipment required, low in raw material cost, environmental friendly and pollution-free in the process, and suitable for preparation on a large scale.

The invention relates to a nitrogen-doped graphene hollow microsphere (NGHM) preparation method. Polystyrene microspheres as templates, graphene as a carbon source and melamine as a nitrogen source are calcined to form NGHM. The prepared NGHM has good oxygen reduction reaction (ORR) catalytic performances. Compared with the commercial Pt/C catalyst, the NGHM has slightly lower OPP onset potential and the same ORR limiting current density. Compared with Pt/C, the NGHM has higher stability and toxicity resistance and has a lower cost. The prepared NGHM can completely replace the commercial Pt/C.

The invention discloses a preparation method and application of a porous carbon-based nanofiber thin film material loaded by a metal single atom and a metal derivative thereof, and belongs to the technical field of preparation of functional nano materials. The preparation method comprises the following steps: fully mixing a metal organic framework precursor MOF with a polymer to prepare a spinning solution, obtaining an MOF nano-particle doped polymer fiber film by virtue of an electrostatic spinning technology, adsorbing metal ions on the surface and inside of the fiber by virtue of dipping, and further performing heat treatment in an inert atmosphere to obtain the metal/nitrogen-doped porous carbon-based hybrid nanofiber thin film material. The carbon-based thin film material prepared by the method has the physical characteristics of abundant active sites, high conductivity, sufficient ion transmission channels, good flexibility, excellent self-supporting structure and the like. The material has the advantages of high activity, high capacity and high stability in the application of electrochemical catalytic reaction and electric storage. The whole material is simple in preparation process, low in energy consumption, environment-friendly and suitable for industrial large-scale production.

The invention discloses a preparation technology of a nano-Fe3O4-V2O5-Au-doped poly-naphthylamine film modified netted glassy carbon electrode. The technology comprises dissolving FeCl3 and NaAc in glycol, drying to obtain particles A; mixing cetyl trimethyl ammonium bromide, n-octane and n-butanol, dividing into two parts, adding ammonium metavanadate and deionized water into one part, stirring to obtain a microemulsion A, adding dilute sulfuric acid into the other part, stirring to obtain a microemulsion B; mixing the microemulsion A and the microemulsion B, centrifuging, washing, roasting to obtain particles B; mixing the particles A and the particles B, adding polyvinyl pyrrolidone, an HAuCl4 solution and the deionized water, shaking and centrifuging, adding washed and dried product, sodium dodecyl benzene sulfonate and naphthylamines into the deionized water and mixing, adding ammonium persulfate, shaking and centrifuging, dissolving the washed product into acetone, adding pre-treated netted glassy carbon, shaking, taking the product out, and drying to obtain the nano-Fe3O4-V2O5-Au-doped poly-naphthylamine film modified netted glassy carbon electrode.

The invention discloses a manganese-cobalt spinel catalyst and a preparation method thereof. The manganese-cobalt spinel catalyst adopts manganese-cobalt spinel as an active component and microporousceramic as a carrier. The manganese-cobalt spinel catalyst not only has excellent mechanical strength, high-temperature resistance, alkali corrosion resistance and good storage stability, but also hasgood catalytic activity in oxygen reduction catalysis.