Korea Institute of Geoscience and Mineral Resources

Korea Institute of Geoscience and Mineral Resources (kigam)

Korea Institute of Geoscience and Material Resources

Kuk Cho

Hee Dong Jang

Dae Sup Kil

Han Kwon Chang

Yong Jae Suh

Byoung-Gyu Kim

Sung-Wook Cho

Hyo-sook Lee

The present invention provides a method for preparing nanoporous Pt/TiOcomposite particles, nanoporous Pt/TiOcomposite particles prepared by the above preparation method, and a fuel cell comprising the nanoporous Pt/TiOcomposite particles. The nanoporous Pt/TiOcomposite particles according to the present invention have a catalytic effect similar to that of commercially available Pt/carbon black and, thus, can be applied to a fuel cell.

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Provided are a method for preparing zinc oxide (ZnO) nanoparticles and a method for preparing ZnO nanofluid using the same. The method for preparing ZnO nanoparticles includes: a) heating deionized water; b) dissolving zinc (Zn) salt in the deionized water to prepare a precursor solution; c) adding solid alkali salt to the precursor solution to prepare a dispersion of ZnO nanoparticles; and d) separating the ZnO nanoparticles by solid-liquid separation and washing them with deionized water. Highly pure, crystalline ZnO nanoparticles with spherical shape and very narrow particle size distribution of 10 to 50 nm can be prepared quickly and at large scale and low cost using inexpensive materials via a stable low-temperature process, without using a dispersant. The associated low-temperature, normal-pressure process produces few harmful materials and may be easily employed for production of ZnO nanoparticles.

Fabrication method of ZnO nano-particle and fabrication method of ZnO nano-fluid using thereof

Disclosed is a method for producing a cerium dioxide nanopowder by flame spray pyrolysis. The method comprises dissolving a cerium compound in an organic solvent to prepare a precursor solution, atomizing the precursor solution into microdroplets using an ultrasonic atomizer, transferring the microdroplets together with an argon gas as a carrier gas to a central portion of a high-temperature diffusion flame burner, subjecting the microdroplets to pyrolysis and oxidation in the central portion of the diffusion flame burner to produce a cerium dioxide nanopowder, and collecting the cerium dioxide nanopowder using a collector. According to the method, a cerium dioxide nanopowder can be continuously produced on a large scale by flame spray pyrolysis. In addition, the particle size and uniformity of the cerium dioxide nanopowder can be controlled by appropriately selecting the kind of the solvent and the concentration of the raw material. Furthermore, flame spray pyrolysis allows the cerium dioxide to have a fluorite crystal structure.

Method for producing cerium dioxide nanopowder by flame spray pyrolysis and cerium dioxide nanopowder produced by the method

The present invention relates to a method for fabricating calcium carbonate nanoparticles dispersed in water from ground calcium carbonate of micrometer (&#x3bc;m) order using beads milling. More particularly, the present invention relates to a method for fabricating calcium carbonate nanoparticles dispersed in water by which a complex aqueous slurry comprising coarse ground calcium carbonate having an average particle size of several micrometers (&#x3bc;m) and a surfactant is subjected to beads milling, such that grinding and dispersion in water of the ground calcium carbonate occur simultaneously, and the resultant calcium carbonate nanoparticles have an average particle size of 10-100 nm and a unimodal clustering distribution.

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Daejeon, South Korea

Kuk Cho