Abstract: A method for forming a coating that is less uneven and more uniform, and has good stability after being formed, by applying a coating-forming composition including a metal compound and/or a halogen-containing compound. The coating is formed by a method including forming a coating by applying a coating-forming composition onto a substrate. The coating-forming composition is a solution including a metal compound and/or a halogen-containing compound, and an amine compound. The metal compound includes one or more metal elements selected from period 2 elements to period 6 elements in the periodic table.

Abstract: A method of producing a porous carbon is provided that can change type of functional groups, amount of functional groups, or ratio of functional groups while inhibiting its pore structure from changing. A method of producing a porous carbon includes: a first step of carbonizing a material containing a carbon source and a template source, to prepare a carbonized product; and a second step of immersing the carbonized product into a template removing solution, to remove a template from the carbonized product, and the method is characterized by changing at least two or more of the following conditions: type of the material, ratio of the carbon source and the template source, size of the template, and type of the template removal solution, to thereby control type, amount, or ratio of functional groups that are present in the porous carbon.

Abstract: An energy conversion device for conversion of chemical energy into electricity. The energy conversion device has a first and second electrode. A substrate is present that has a porous semiconductor or dielectric layer placed thereover. The porous semiconductor or dielectric layer can be a nano-engineered structure. A porous catalyst material is placed on at least a portion of the porous semiconductor or dielectric layer such that at least some of the porous catalyst material enters the nano-engineered structure of the porous semiconductor or dielectric layer, thereby forming an intertwining region.

Abstract: Aspects of the present disclosure are directed towards a method of making a scandium metal-doped nanoparticle. The method includes mixing a cobalt salt, an iron salt, and an acid in water to form a solution including CoFe2O4; mixing a nickel-iron oxide solution and a scandium oxide solution to form a solution including NiSc0.03Fe1.97O4; mixing the cobalt iron oxide solution and the nickel scandium iron oxide solution to form a sol-gel mixture including CoFe2O4/(NiSc0.03Fe1.97O4)x (0?x?5); adjusting the pH of the sol-gel mixture 6 to 8 with a base to form a first mixture; heating the first mixture to form a powder, and calcining the powder to form the scandium metal-doped nanoparticle of formula CoFe2O4/(NiSc0.03Fe1.97O4)x (0?x?5). The present disclosure also describes an electrode including the scandium metal-doped nanoparticles. The electrode may be used in magnetic supercapacitors.

Abstract: In an embodiment, the present disclosure pertains to a method of creating a supercapacitor. The method includes forming an anode and a cathode, each composed of a substrate having at least one of a lignin, a lignin-based composite, activated carbon, a plant extract, a cellulose by-product, biofuel waste, one or more metals, a metal oxide, a monometallic tungstate, or a bimetallic tungstate, and sandwiching an electrolyte coated separator between the anode and the cathode. In an addition embodiment, the present disclosure pertains to an electrode composed of a particle-decorated lignin. In some embodiments, the particle-decorated lignin includes particles that can include, without limitation, MnO2, NiWO4, MnO2, NiCoWO4, CoWO4, and combinations thereof. In a further embodiment, the present disclosure pertains to a supercapacitor made via the methods of the present disclosure.

Abstract: A fuel cell catalyst material includes metal catalyst particles formed of a metal material and a carbon-based coating composition at least partially coating at least some of the metal catalyst particles. The carbon-based coating composition includes a carbon network. The carbon-based coating composition is doped with a dopant. The carbon-based coating composition includes a number of defects formed by one or more vacated carbon atoms in the carbon network.

Abstract: An electrocatalyst includes a carbon substrate, metal oxide particles dispersed on the carbon substrate, and metal catalyst particles. The metal catalyst particles are metal substitutions in the metal oxide particles, or adsorbed on the metal oxide particles.

Abstract: A membrane electrode assembly includes an electrolyte membrane, and a pair of electrode layers which sandwich the electrolyte membrane. The pair of electrode layers include a pair of catalyst layers which sandwich the electrolyte membrane, and a pair of gas diffusion layers disposed on the pair of catalyst layers on opposite sides to the electrolyte membrane. At least one catalyst layer contains a fibrous electric conductor, catalyst particles, a particulate electric conductor, and a proton-conductive resin. The at least one catalyst layer has a first region at a distance of 200 nm or less from the fibrous electric conductor, and a second region at a distance of more than 200 nm from the fibrous electric conductor. Pores are present in the first and second regions. A mode diameter M1 of the pores in the first region and a mode diameter M2 of the pores in the second region satisfy M1<M2.

Abstract: Provided are a separator for a secondary battery and an electrochemical device using the same. More specifically, provided is a composite separator having a more excellent cycle life and including a coating layer which is not easily swollen in an electrolyte solution. In the composite separator for a secondary battery according to an aspect of the present invention, distortion or lifting phenomenon is suppressed even when the heat and pressure are applied without significant decrease in permeability of the separator.

Abstract: A method for manufacturing a membrane-electrode assembly for a fuel cell comprises the following steps: a first step during which a chemical catalyst element is deposited on a first face of an ion-exchanging membrane, the membrane being held on a support film; a second step during which the membrane is unglued from the support film; a third step during which the membrane is inserted between two reinforcing elements; and a fourth step during which a chemical catalyst element is deposited on the part left free of the second face of the membrane.

Abstract: Methods and compositions for making fuel cell components are described. In one embodiment, the method comprises providing a substrate, and forming or adhering an electrode on the substrate, wherein the forming includes depositing an aqueous mixture comprising water, a water-insoluble component, a catalyst, and an ionomer. The water-insoluble component comprises a water-insoluble alcohol, a water-insoluble carboxylic acid, or a combination thereof. The use of such water-insoluble components results in a stable liquid medium with reduced reticulation upon drying, reduced dissolution of the substrate, and reduced penetration of the pores of the substrate.

Abstract: The present invention relates to a catalyst composition, comprising tin oxide particles which are at least partially coated by a noble metal oxide layer, wherein the composition contains iridium and ruthenium in a total amount of from 10 wt % to 38 wt %, and all iridium and ruthenium is oxidized, —has a BET surface area of from 5 to 95 m2/g, and —has an electrical conductivity at 25° C. of at least 7 S/cm.

Abstract: Provided are a method of forming a gas diffusion layer on carbon paper, the method being capable of balancing smoothness with air permeability and water drainage ability in the gas diffusion layer as an underlayer, as well as the carbon paper having the gas diffusion layer formed thereon used in fuel cells. The method of forming a gas diffusion layer (L2) on carbon paper (CP) used in fuel cells includes the steps of: forming a water-repellent layer (L1) on the surface of the carbon paper (CP), forming a crack (CR) in the water-repellent layer (L1), and forming the gas diffusion layer (L2) on the water-repellent layer (L1) having the crack (CR) formed therein.

Abstract: A gas diffusion electrode including: a conductive porous substrate and a microporous layer on at least one side of the conductive porous substrate; in which the total of regions passing through the microporous layer in the thickness direction has an area ratio of 0.1% or more and 1% or less; and in which the microporous layer has a portion that has penetrated into the conductive porous substrate (hereinafter referred to as penetration portion), the penetration portion having a thickness ratio of 30% or more and 70% or less with respect to 100% of the thickness of the microporous layer. The gas diffusion electrode used for fuel cells affords fuel cells having high water removal performance and high power generation performance.

Abstract: A synthesis method of a metal catalyst having carbon shell, includes: a) forming a metal-ligand complex without further chemical additives by mixing a ligand with a metal precursor; b) separating the metal-ligand complex and collecting the separated metal-ligand complex; c) supporting the collected metal-ligand complex to a support by mixing the collected metal-ligand complex with the support in a solvent; and d) treating a composite consisting of the metal-ligand complex and the support by heating.

Abstract: A pyrolyzed MOF catalyst for in the carbon dioxide reduction reaction and methods of making the catalyst. The catalysts are composed of highly porous transition metal organic frameworks exhibiting large pores with regular distribution of transition metals within the structure.

Abstract: A gas diffusion electrode in which a microporous layer is provided on at least one surface of a conductive porous substrate, wherein the areas obtained by dividing the cross section perpendicular to the plane of the microporous layer into three equal parts in the thickness direction are a first area, a second area, and a third area, with respect to the conductive porous substrate side, the fluorine strength of the third area being 0.8 to 1.2 times the fluorine strength of the second area.

Abstract: The invention relates to methods for hydrocracking or hydrotreating hydrocarbon containing feedstocks. This is accomplished via the use of a catalyst which comprises a ? zeolite of *BEA framework, where a portion of aluminum atoms in the *BEA framework have been substituted by from 0.1-5.0 wt % of each of Ti and Zr, calculated on an oxide basis.

Abstract: The present invention is a catalyst for a solid polymer fuel cell including: catalyst particles of platinum, cobalt and manganese; and a carbon powder carrier supporting the catalyst particles, wherein the component ratio (molar ratio) of the platinum, cobalt and manganese of the catalyst particles is of Pt:Co:Mn=1:0.06 to 0.39:0.04 to 0.33, and wherein in an X-ray diffraction analysis of the catalyst particles, the peak intensity ratio of a Co—Mn alloy appearing around 2?=27° is 0.15 or less on the basis of a main peak appearing around 2?=40°. It is particularly preferred that the catalyst have a peak ratio of a peak of a CoPt3 alloy and an MnPt3 alloy appearing around 2?=32° of 0.14 or more on the basis of a main peak.

Abstract: Functionalized graphene comprising graphene, a metal dispersed throughout the graphene, wherein the metal comprises Pt, Rh, Pd, Ag, Au, Ni, Os, Ir, alloys thereof, oxides thereof, or mixtures thereof, and a first functional group covalently bonded to the graphene, wherein the first functional group comprises sulfonate, SO3?, Carboxylate, COO?, a tertiary amine, NR3+, where R is H, alkyl, aryl, or combinations thereof, polybenzimidazole (PBI), poly(ethylene oxide) (PEO), polyphenylene oxide (PPO), polyaniline, or mixtures thereof are disclosed. Methods of manufacture are also disclosed.

Abstract: The present invention is a method for producing a porous metal body or a method for producing an electrode catalyst, which is capable of simplifying the production process and improving the production efficiency by not requiring a step of immersion in an acid treatment solution. A method for producing a porous metal body according to the present invention comprises: a step for forming a metal resin-containing layer, which contains a metal and a resin that has a lower melting point than the metal, on a base; and a step for obtaining a porous metal body by subjecting the metal resin-containing layer to a heat treatment, thereby sintering the metal and removing the resin from the metal resin-containing layer.

Abstract: Methods, structures, devices and systems are disclosed for fabrication of microtube engines using membrane template electrodeposition. Such nanomotors operate based on bubble-induced propulsion in biological fluids and salt-rich environments. In one aspect, fabricating microengines includes depositing a polymer layer on a membrane template, depositing a conductive metal layer on the polymer layer, and dissolving the membrane template to release the multilayer microtubes.

Abstract: A method for producing a cell structure includes: a step of firing a laminated body of a layer containing an anode material and a layer containing a solid electrolyte material, to obtain a joined body of an anode and a solid electrolyte layer; a step of laminating a layer containing a cathode material on a surface of the solid electrolyte layer, and firing the obtained laminated body to obtain a cathode. The anode material contains a metal oxide Ma1 and a nickel compound. The metal oxide Ma1 is a metal oxide having a perovskite structure represented by A1x1B11-y1M1y1O3-? (wherein: A1 is at least one of Ba, Ca, and Sr; B1 is at least one of Ce and Zr; M1 is at least one of Y, Yb, Er, Ho, Tm, Gd, In, and Sc; 0.85?x1?0.99; 0<y1?0.5; and ? is an oxygen deficiency amount).

Abstract: A gas-diffusion electrode substrate includes an electrode substrate and a microporous layer (MPL) disposed on one surface of the electrode substrate, wherein the gas-diffusion electrode substrate has a thickness of 110 ?m or more and 240 ?m or less, and where a cross section of the gas-diffusion electrode substrate is divided into a part having the MPL and a part having no MPL, and the part having no MPL is further equally divided into a part (CP1 cross section) in contact with the MPL and a part (CP2 cross section) not in contact with the MPL, the CP1 cross section has an F/C ratio of 0.03 or more and 0.10 or less and the CP2 cross section has an F/C ratio less than 0.03, wherein F is a mass of a fluorine atom, and C is a mass of a carbon atom.

Abstract: A printed gas sensor is disclosed. The sensor may include a partially porous substrate, an electrode layer, an electrolyte layer, and an encapsulation layer. The electrode layer comprises one or more electrodes that are formed on one side of the porous substrate. The electrolyte layer is in electrolytic contact with the one or more electrodes. The encapsulation layer encapsulates the electrode layer and electrolyte layer thereby forming an integrated structure with the partially porous substrate.

Abstract: The purpose of the present invention is to provide a carbon sheet that is suitably employed in a gas-diffusion-electrode substrate that has excellent flooding resistance and with which it is possible to suppress internal peeling of the carbon sheet. In order to achieve the aforementioned purpose, the present invention has the following configuration.

Abstract: A manufacturing method of nitrogenous carbon electrode and flow cell provided therewith is disclosed. Firstly, a preformed body is performed by mixing a carbon material, a polymeric material and a modifier. A formation process is performed on the preformed body to obtain a formed body. A high sintering is then performed, such that a part of the polymeric material is decomposed and then removed, while the other part of polymeric material is cooperated with the carbon material to form a skeletal structure including a plurality of pores, and that the nitrogen in the modifier is adhered to the skeletal structure to form a nitrogenous functional group, and then form a nitrogenous carbon electrode. The nitrogenous carbon electrode may be applied to the flow cell. Thereby, electric conductivity in a vertical direction may be enhanced, so as to reduce internal resistance of the flow cell and increase discharge power.

Abstract: The present application relates to a fuel cell and a method of manufacturing the same.

Abstract: The present invention is a catalyst for a solid polymer fuel cell including: catalyst particles of platinum, cobalt and manganese; and a carbon powder carrier supporting the catalyst particles, wherein the component ratio (molar ratio) of the platinum, cobalt and manganese of the catalyst particles is of Pt:Co:Mn=1:0.06 to 0.39:0.04 to 0.33, and wherein in an X-ray diffraction analysis of the catalyst particles, the peak intensity ratio of a Co—Mn alloy appearing around 2?=27° is 0.15 or less on the basis of a main peak appearing around 2?=40°. It is particularly preferred that the catalyst have a peak ratio of a peak of a CoPt3 alloy and an MnPt3 alloy appearing around 2?=32° of 0.14 or more on the basis of a main peak.

Abstract: A gas diffusion electrode and a method for manufacturing the same, the gas diffusion electrode being used for a fuel cell and configured by forming a microporous layer containing conductive microparticles and water-repellent resin on at least one surface of a conductive porous base material, wherein the gas diffusibility in the thickness direction thereof is 30% or more, the conductive porous base material has a sliding angle of 70° or less and a porosity of 80% or more, and the microporous layer has a thickness of 10-50 ?m inclusive, and a porosity of 60-95% inclusive.

Abstract: A manufacturing device of a membrane-electrode assembly for fuel cell includes a membrane unwinder unwinding and supplying a polymer electrolyte membrane of a roll shape; a film unwinder unwinding and supplying a release film of a roll shape respectively coated with an anode catalyst electrode layer and a cathode catalyst electrode layer with a predetermined interval in an upper and lower sides of the polymer electrolyte membrane; upper and lower bonding rolls respectively disposed at the upper and lower sides of a progressing path of the polymer electrolyte membrane and the release film and pressed to an upper surface and a lower surface of the polymer electrolyte membrane; and a protection film unwinder unwinding and supplying a protection film between adhered surfaces of the release film and the upper and lower bonding rolls.

Abstract: The present invention relates to an efficient, non-metal, N-doped porous carbon electrocatalyst for oxygen reduction reaction and a process for the preparation of using g-C3N4 as a nitrogen precursor, metal organic frameworks (MOF) as a carbon template having high specific surface area, large number of active sites and large pore volume.

Abstract: Provided is a method for producing a catalyst, including: (i) mixing a core metal salt that serves as a material for a core metal, and a complexing agent (a) to produce a core metal complex solution containing a core metal complex; (ii) mixing a shell metal salt that serves as a material for a shell metal, and a complexing agent (b) to produce a shell metal complex solution containing a shell metal complex; (iii) mixing a carbon powder and a dispersing agent to produce a carbon powder dispersion; (iv) mixing the core metal complex solution, the shell metal complex solution, and the carbon powder dispersion, and reducing the core metal complex and the shell metal complex on the carbon powder by using at least one reducing agent; and (v) drying and baking at a predetermined temperature the carbon powder resulting from Step (iv), said carbon powder having a core-shell structure that includes the core metal and the shell metal.

Abstract: A micro porous layer and a catalyst layer are integrated into a sheet so that a fuel cell electrode sheet is formed. The electrode sheet is obtained by applying an MPL ink containing a carbon material and a binder to a supporting sheet and heat-treating the ink, and applying a catalyst ink containing a catalyst to the obtained micro porous sheet and drying it. An electrode assembly in which the electrode sheets is laminated onto both sides of a solid polymer electrolyte membrane, is obtained by laminating the electrode sheets formed on the supporting sheets to the solid polymer electrolyte membrane, and thereafter peeling off the supporting sheets.

Abstract: In a membrane electrode assembly, electrode catalyst layers are provided respectively on both surfaces of an electrolyte membrane. Each of the electrode catalyst layers includes polymer electrolyte and catalyst. In each of the electrode catalyst layers, the weight of a component of the polymer electrolyte contained in one surface facing the electrolyte membrane is twice as large as, or more than twice as large as the weight of the component of the polymer electrolyte contained in another surface.

Abstract: The present invention relates to a method of manufacturing a hydrogen transport membrane and the composite article itself. More specifically, the invention relates to producing a membrane substrate, wherein the ceramic substrate is coated with a metal oxide slurry, thereby eliminating the need for an activation step prior to plating the ceramic membrane through an electroless plating process. The invention also relates to modifying the pore size and porosity of the substrate by oxidation or reduction of the particles deposited by the metal oxide slurry.

Abstract: Provided is a carbon-fiber nonwoven cloth with low resistance to gases or liquids passing through, and low resistance in the thickness direction to heat or electricity, which is particularly appropriate for a gas diffusion electrode of a polymer electrolyte fuel cell; the cloth having an air gap with a diameter of at least 20 ?m, at least some of the carbon fibers being continuous from one surface to the other surface, and the apparent density being 0.2-1.0 g/cm3, or, having an air gap with a diameter of at least 20 ?m and at least some of the carbon fibers being mutually interlaced, and further, at least some of the carbon fibers being oriented toward the thickness direction and the apparent density being 0.2-1.0 g/cm3.

Abstract: An apparatus for manufacturing a membrane-electrode assembly for a fuel cell is provided. The apparatus includes a sub-gasket feeding unit that forms first electrode windows, unrolls a first sub-gasket sheet, and supplies the sheet to a transfer line. An electrode membrane loading unit installed over the transfer line forms electrode catalyst layers on both faces of an electrolyte membrane, collects the electrode membrane sheet cut, and loads the sheets onto first electrode windows. A sub-gasket loading unit installed over the transfer line forms second electrode windows, collects a second sub-gasket sheet, and loads the sheets on the electrode membrane sheet. MEA bonding units installed on the transfer line bond the first sub-gasket sheet, the electrode membrane sheet, and the second sub-gasket sheet mutually stacked while passing the first sub-gasket sheet, the electrode membrane sheet, and the second sub-gasket sheet between a pair of hot rollers along the transfer line.

Abstract: Compositions and methods comprising metal organic frameworks (MOFs) and related uses are generally provided. In some embodiments, an MOF comprises a plurality of metal ions, each coordinated with at least one ligand comprising at least two unsaturated N-heterocyclic aromatic groups arranged about an organic core. In some embodiments, an MOF may be used in applications related to water adsorption.

Abstract: The invention relates to carbon nanotube-containing composites as biosensors to detect the presence of target clinical markers, methods of their preparation and uses in the medical field. The invention is particularly suitable for the detection in patient biological specimens of bone markers and tissue markers. The biosensors of the invention include carbon nanotubes deposited on a substrate, gold nanoparticles deposited on the carbon nanotubes and, binder material and biomolecule deposited on the gold-coated carbon nanotubes. The biomolecule is selected to interact with the target clinical markers. The biosensor can be used as an in-situ or an ex-situ device to detect and measure the presence of the target clinical markers.

Abstract: A fuel cell, a reinforced membrane electrode assembly and a method of fabricating a reinforced membrane electrode assembly. The method comprises depositing an electrode ink onto a first substrate to form a first electrode layer, applying a first porous reinforcement layer on a surface of the first electrode layer to form a first catalyst coated substrate, depositing a first ionomer solution onto the first catalyst coated substrate to form a first ionomer layer, and applying a membrane porous reinforcement layer on a surface of the first ionomer layer to form a reinforced membrane layer.

Abstract: A particle exhibiting catalytic activity comprising (a) an inner core formed of an alloy material; and (b) an outer shell formed of a metal material surrounding the inner core, wherein the alloy material is selected such that the inner core exerts a compressive strain on the outer shell.

Abstract: A fuel cell is configured to comprise a power generation layer including an electrolyte membrane, an anode and a cathode, separators and a gas flow path layer provided between the power generation layer and the separator. The gas flow path layer is structured by a plurality of corrugated elements. Each corrugated element has a corrugated cross section where first convexes that are convex toward the separator and second convexes that are convex toward the power generation layer are alternately arranged. The plurality of corrugated elements are arranged, such that a top surface of the first convex in one corrugated element and a bottom surface of the second convex in an adjacent corrugated element cooperatively form an integral surface, and a plurality of through holes are formed between the respective adjacent corrugated elements.

Abstract: The present application provides a method for fabricating core-shell particles, including: forming a first solution by adding a first metal salt and a first surfactant to a first solvent; forming core particles including a first metal included in the first metal salt by adding a first reducing agent to the first solution; forming a second solution by adding the core particles, a second metal salt, and a second surfactant to a second solvent; and forming core-shell particles by adding a second reducing agent to the second solution and forming shells on the surface of the core particle, in which the first surfactant and the second surfactant are polyoxyethylene, polyoxyethylene sorbitan monolaurate or polyoxyethylene oleyl ether, and core-shell particles fabricated by the method.

Abstract: A method for manufacturing an alloy catalyst for a fuel cell is disclosed. The method for manufacturing an alloy catalyst for a fuel cell may include predetermined processes and reaction conditions, such that iridium is alloyed to platinum contained in a cathode carbon support catalyst. Accordingly, time for stabilizing charge on the carbon surface may be reduced and a metal particle size may be controlled, thereby manufacturing high quality products having uniform metal particle distribution and improved durability. In addition, corrosion of a cathode carbon support catalyst in a harsh condition such as vehicle driving may be prevented.

Abstract: A method of manufacturing a fuel cell. An insulating member has a plurality of communication holes disposed on a side of a gas diffusion layer, which is formed by stacking a layer made of a carbon fiber and a water-repellent layer, where the water-repellent layer is provided. The gas diffusion layer and the insulating member are sandwiched by a pair of electrodes, and a pair of contact pressure plates are disposed on respective rear surfaces of the pair of electrodes so as to sandwich the pair of electrodes so that the gas diffusion layer is pressurized by the pair of contact pressure plates. When a voltage is applied to the pair of electrodes while maintaining the pressurized state, the protrusion portion of the carbon fiber is burned and removed by Joule heat.

Abstract: The present invention pertains to novel core-shell particles comprising a core of alumina and a shell of cobalt oxide, characterized in that they are spherical with a number average diameter, as measured by TEM, of between 10 and 30 nm. This invention also pertains to the method for preparing these core-shell particles and to their uses in the manufacture of a catalyst.

Abstract: An electrode catalyst for a fuel cell, a membrane electrode assembly including the electrode catalyst, and a fuel cell including the electrode catalyst. The electrode catalyst has excellent electrochemical activity compared to the currently commercially available Pt/C catalyst and is much cheaper than a catalyst using platinum. The electrode catalyst includes tungsten carbide having a specific surface area of about 10 to about 30 m2/g, and a metal catalyst comprising palladium (Pd) or palladium alloy.

Abstract: This fuel-cell gas diffusion layer includes a conductive porous layer constituted by: porous carbon formed so as to have a porosity distribution substantially uniform in a stacking direction with respect to a membrane electrode assembly; and a PTFE resin arranged dispersedly across the inside of the carbon. When a ratio of a surface of the carbon to a surface that is exposed without being covered with the PTFE resin is defined as an exposure ratio, the exposure ratio of a surface, on a cathode electrode side, of the conductive porous layer, is higher than the exposure ratio, on a diffusion-layer base material side, of the conductive porous layer.

Abstract: The production method according to the present invention includes a process for producing fine particles formed of a non-precious metal; a process for forming a shell of a precious metal on the respective surfaces of the fine particles of the non-precious metal; and a process for collecting a catalyst from a fluid reaction mixture. A fine metal particle-carrying catalyst prepared by such a production method includes fine non-precious metal particles as the cores thereby reducing the usage of a precious metal to achieve suppression of a cost increase. Since it includes a shell portion formed of a precious metal, it exhibits excellent catalytic activity.