42results about How to "Increase ORR activity" patented technology

The invention discloses a Co@NC high-dispersion core-shell structure catalyst, and a preparation method and an application of the catalyst, and belongs to the technical field of energy source materials and electrochemistry. The preparation method of the catalyst comprises the steps of taking glucose as a C source, taking cyanoguanidine as a C-N source, taking Co(No3).6H2O as a Co source, and performing high temperature calcination. The cyanoguanidine performs high temperature decomposition to generate two-dimensional flaky g-C3N4; the glucose performs high temperature decomposition to generatea carbon intermediate and a metal species which are inserted into flakes of g-C3N4; and Co nanoparticles coated by an N-C layer in the catalyst are uniformly dispersed on a graphene carbon layer. Thecatalyst can serve as a cathode oxygen reduction electrocatalyst of a metal-air battery and a fuel battery. The catalyst is cheap and easy obtaining in raw material, and simple in preparation technology; amplification production is facilitated; in-situ decomposition of the cyanoguanidine provides rich N doped active sites for the catalyst; rich mesoporous structures are formed; the activity of the catalyst is improved; a channel is provided for transfer and transport of reaction participation substances in an ORR process; a mass transfer demand of a reaction process is met; and the catalyst is good in stability and high in methanol resistance.

The invention discloses a preparation method for a nitrogen-boron-doped carbon-based catalyst, which belongs to the technical field of catalytic materials. The method comprises the following steps: pretreating a carbon material; then mixing the pretreated carbon material with a nitrogen supplying agent, a boron supplying agent and an activator and carrying out mechanical ball milling; then subjecting a mixture obtained after ball milling to nitrogen-boron co-penetration heat treatment of the carbon material at a temperature of 500 to 1100 DEG C under the protection of inert gas for 1 to 3 h; and finally carrying out pickling so as to prepare the nitrogen-boron-doped carbon-based catalyst. The nitrogen-boron-doped carbon-based catalyst prepared by using the method can be used as a negative electrode oxygen reducing catalyst for a fuel cell; the preparation method has the advantages of low prices of raw materials, simple process, low requirements on equipment and applicability to large-scale production of the catalyst; and the catalyst shows good oxygen reduction activity and stability under both acidic and alkaline conditions.

The invention relates to a FeCx@NC core-shell structured catalyst and a preparation method therefor. The FeCx@NC core-shell structured catalyst takes iron and FeCx nanoparticle mixture as the core, and takes nitrogen and FeCx-doped carbon as the shell, and has a mesoporous structure with a specific surface area of 500-900m<2>g<-1>. The preparation method for the core-shell structured catalyst comprises the steps of preparing a polyaniline and glucose composite material firstly; performing calcining for one time to prepare a Fe-N-C catalyst; and finally performing calcining for the second time to obtain the FeCx@NC catalyst. The catalyst is high in oxygen reduction activity and high in stability; the raw materials, such as the carbon source and the nitrogen source used by the preparation method are low in cost, so that the production cost for producing a Fe-N-C material by the conventional pyrolysis method can be lowered; meanwhile, the preparation method is simple and easy to implement; and in addition, the core-shell structured catalyst provided by the invention has relatively high electrocatalytic activity, and can be widely applied to the negative electrode catalyst of a proton exchange membrane fuel cell, an alkali negative ion exchange membrane fuel cell, and a metal air battery.

A cathode electrode for a fuel cell, includes a conductive carrier having pores and a catalyst having a platinum alloy supported in the pores of the conductive carrier, wherein the catalyst has in a pore diameter range of 2 to 6 nm when diameters of the pores is plotted in relation with volumes of the pores a peak value of more than 1 cm³/g and also a BET specific surface area of 1300 m²/g.

The invention provides a high-activity Co-Ni-Fe co-inlaid non-noble metal catalyst as well as a preparation method and application thereof. Based on a preparation method of an organic metal framework compound, the high-activity Co-Ni-Fe co-inlaid non-noble metal catalyst is synthesized by optimizing the contents of Co, Ni and Fe. The multi-metal inlaid catalyst has three active sites of Co-N-C, Ni-N-C and Fe-N-C, and after optimization, the Co-Ni-Fe co-inlaid non-noble metal catalyst has no metal agglomeration phenomenon. Besides, due to rich active sites, the catalyst shows excellent electrochemical activity, the half-wave potential in a 0.1 M KOH solution is as high as 0.881 V (vs.RHE), and the half-wave potential in a 0.1 M HCLO4 solution is as high as 0.798 V (vs.RHE), which are far superior to those of a conventional non-noble metal catalyst. The catalyst has a huge application prospect in the aspect of effectively reducing the cost of the proton exchange membrane fuel cell.

The invention discloses a supported platinum-palladium-gold ternary alloy nano-catalyst as well as a preparation method and application thereof. The preparation method comprises the following steps: S01, measuring a proper amount of HCl solution of PdCl2 in a beaker, slowly adding a certain amount of ammonia water under stirring conditions until the system is colorless, and continuously stirring for at least 30 minutes for later use; S02, weighing a certain amount of pretreated carbon support in another beaker, adding a proper amount of aqueous solution of H2PtCl6 and H2AuCl6, and uniformly dispersing in a low-temperature ultrasonic machine; S03, adding the solution in S01 into the beaker in S02, and uniformly dispersing at room temperature so as to obtain carbon mud; and S04, stirring and evaporating the carbon mud in S03 until obvious liquid does not exist in the carbon mud. The method is easy to operate, does not have any surfactant and is free from pollution and environmentally friendly, and the catalyst prepared by the method is stable in performance and high in repeatability and can be produced in batches.

An electrode catalyst includes a carbon (C) carrier; a perovskite-type oxide catalyst containing lanthanum (La), manganese (Mn), and oxygen (O) elements; and a metal catalyst containing a silver (Ag) element. The perovskite-type oxide catalyst is located on the carrier and the metal catalyst is also located on the carrier.

The invention discloses an iridium monatomic catalyst and a preparation method and application thereof, the catalyst is a nanostructure system, carbon atoms, nitrogen atoms and iridium atoms are distributed in the nanostructure system, in the nanostructure system, the carbon atoms form a carrier structure, and the iridium atoms and the nitrogen atoms are embedded in the carrier structure. After the prepared catalyst is applied, the problems that an energy supply system in a self-energy-supply sensing system is poor in stability and low in glucose detection sensitivity can be solved.

The invention relates to a fuel cell oxygen reduction catalyst with high-density active sites and a preparation method thereof, the catalyst is composed of specially designed high-density Fe-Nx-C and platinum nanoparticles loaded on the Fe-Nx-C, and the catalyst is characterized in that the high-density Fe-Nx active sites are not mutually agglomerated; however, the Fe-Nx-C substrate with a special structure has very good oxygen reduction activity, and a small amount of nano platinum particles loaded on the Fe-Nx-C substrate can fully exert the activity of the Fe-Nx-C substrate due to the synergistic effect of a carrier and metal instead of regional intensive active sites under the action of thermal coupling. According to the method, the problem of insufficient performance of a traditional carbon substrate is solved to a certain extent, the use amount of platinum is reduced, and the fuel cell oxygen reduction catalyst has a good prospect in practical application of the low-temperature hydrogen energy fuel cell.

The invention provides a catalyst with low Pt loading capacity, a preparation method and application thereof, and the method comprises the following steps: loading PtCeO2 on a non-noble metal catalyst to prepare PtCeO2 (at) M-N-C, M being a non-noble metal, C being a carbon element, and N being a nitrogen element. The method is suitable for various forms of non-noble metal catalysts, in addition, the reaction conditions of the Pt salt and the Ce salt are mild, a subsequent high-temperature pyrolysis process is not needed, Pt and CeO2 are in a highly dispersed state, and the utilization rate of Pt can be improved by improving the dispersity of Pt, so that the cost is reduced.

The invention discloses an iron-nitrogen doped core-shell carbon sphere material and a preparation method thereof, and relates to the technical field of core-shell materials. The preparation method ofthe iron-nitrogen doped core-shell carbon sphere material comprises the following steps: (1) preparing polydopamine spheres; (2) preparing an iron-doped metal organic framework coated polydopamine sphere compound; and (3) preparing the iron-nitrogen doped core-shell carbon sphere material. Compared with a Pt/C catalyst sold in the market, the iron-nitrogen doped core-shell carbon sphere materialprepared by the method provided by the invention shows higher ORR activity.

The invention relates to a cobalt-based oxygen reduction electro-catalytic material and a preparation method thereof, and solves the problems of low catalytic activity, small catalytic active site density, low active site utilization rate, complicated preparation, high cost and the like of the existing non-noble metal ORR catalyst. ZIF-67 is used as a precursor, the coordination environment of a carbon-supported cobalt-based catalyst is accurately regulated and controlled through process parameters of carbonization and vulcanization processes, an electro-catalytic material which is mainly composed of Co-S-C, coexists with Co-N-C and Co-C and has a phase composition of Co1-xS is obtained, and the electro-catalytic activity of a single active site is remarkably enhanced. Moreover, cobalt atoms of the material are uniformly distributed in a carbon skeleton at high density, so that the density of active sites is improved; meanwhile, the material has a larger average pore size on the basis of high specific surface area, and the utilization rate of active sites is improved. The preparation method of the cobalt-based electrocatalyst is easy and convenient to operate, the consistency of synthetic materials is high, and the cobalt-based electrocatalyst has application and popularization value.