Abstract: The present invention provides a method of synthesizing a nano-sized transition metal catalyst on a carbon support, including dissolving a stabilizer in ethanol thus preparing a mixture solution, adding a support to the mixture solution thus preparing a dispersion solution, dissolving a transition metal precursor in ethanol thus preparing a precursor solution, mixing the precursor solution with the dispersion solution with stirring, and then performing reduction, thus preparing the nano-sized transition metal catalyst. This method enables the synthesis of transition metal nanoparticles supported on carbon powder having a narrow particle size distribution and a wide degree of dispersion through a simple process, and is thus usefully applied to the formation of an electrode material or the like of a fuel cell.

Abstract: Disclosed is a method for preparing nickel or palladium nanoparticles supported on a carbon support. To a mixture solution wherein a stabilizer is dissolved in 1,2-propanediol, a carbon support is added to prepare a dispersion. Then, a precursor solution wherein a nickel or palladium precursor dissolved in 1,2-propanediol is mixed therewith and stirred. Then, nickel or palladium nanoparticles supported on the carbon support are prepared by reduction. The disclosed method for preparing nickel or palladium nanoparticles supported on a carbon support allows preparation of nanoparticles with narrow particle size distribution and good dispersibility through a simple process and the resulting nickel or palladium nanoparticles may be usefully applied, for example, as electrode materials of fuel cells.

Abstract: The present invention features a method for preparing core-shell nanoparticles supported on carbon. In particular, the present invention features a method for preparing core-shell nanoparticles supported on carbon, including: dispersing core nanoparticle powder supported on carbon in ethanol; adding a metal precursor which forms a shell and hydroquinone thereto; and mixing and reducing the same. Preferably, the disclosed method for preparing core-shell nanoparticles supported on carbon enables coating of transition metal nanoparticles including platinum on the surface of core metal nanoparticles at a monolayer level. Prepared core-shell nanoparticles of the present invention may be useful as catalysts or electrode materials of fuel cells.

Abstract: The present invention features a method for preparing core-shell nanoparticles supported on carbon. In particular, the present invention features a method for preparing core-shell nanoparticles supported on carbon, including: dispersing core nanoparticle powder supported on carbon in ethanol; adding a metal precursor which forms a shell and hydroquinone thereto; and mixing and reducing the same. Preferably, the disclosed method for preparing core-shell nanoparticles supported on carbon enables coating of transition metal nanoparticles including platinum on the surface of core metal nanoparticles at a monolayer level. Prepared core-shell nanoparticles of the present invention may be useful as catalysts or electrode materials of fuel cells.

Abstract: Disclosed is a method for preparing nickel or palladium nanoparticles supported on a carbon support. To a mixture solution wherein a stabilizer is dissolved in 1,2-propanediol, a carbon support is added to prepare a dispersion. Then, a precursor solution wherein a nickel or palladium precursor dissolved in 1,2-propanediol is mixed therewith and stirred. Then, nickel or palladium nanoparticles supported on the carbon support are prepared by reduction. The disclosed method for preparing nickel or palladium nanoparticles supported on a carbon support allows preparation of nanoparticles with narrow particle size distribution and good dispersibility through a simple process and the resulting nickel or palladium nanoparticles may be usefully applied, for example, as electrode materials of fuel cells.

Abstract: The present invention provides a method of synthesizing a nano-sized transition metal catalyst on a carbon support, including dissolving a stabilizer in ethanol thus preparing a mixture solution, adding a support to the mixture solution thus preparing a dispersion solution, dissolving a transition metal precursor in ethanol thus preparing a precursor solution, mixing the precursor solution with the dispersion solution with stirring, and then performing reduction, thus preparing the nano-sized transition metal catalyst. This method enables the synthesis of transition metal nanoparticles supported on carbon powder having a narrow particle size distribution and a wide degree of dispersion through a simple process, and is thus usefully applied to the formation of an electrode material or the like of a fuel cell.

Abstract: A method of preparing a platinum alloy catalyst for a fuel cell electrode includes: (a) adding a carbon material, a platinum precursor, and a transition metal precursor to ethanol and dispersing the mixture; (b) adding sodium acetate powder or an ammonia solution containing ethanol as a solvent to the solution obtained in step (a) and stirring the resulting solution; (c) adding sodium borohydride to the solution obtained in step (b) and reducing the metal ions of the platinum precursor and the transition metal precursor; and (d) obtaining a platinum alloy catalyst in the form of powder through washing and drying processes. This method can reduce the amount of platinum to be used for manufacturing a fuel cell electrode and thereby reduce the manufacturing cost.

Abstract: The invention relates to a method of manufacturing an FBAR having a cap made of solid metal. The method includes preparing a substrate and stacking a lower electrode, a piezoelectric film and an upper electrode on the substrate to form a resonance region. The method also includes forming a passivation layer above substantially an entire area of the resonance region and its adjacent region to protect the resonance region and forming a first photoresist layer on the passivation layer. The first photoresist layer exposes a sidewall region which surrounds the resonance region. The method further includes filling in the sidewall region with metal and forming a roof with the same metal on the resonance region surrounded by the sidewall region, thereby forming a cap composed of the sidewall and the roof.