摘要:
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.
摘要:
The present invention provides a method for preparing nanoporous Pt/TiO2 composite particles, nanoporous Pt/TiO2 composite particles prepared by the above preparation method, and a fuel cell comprising the nanoporous Pt/TiO2 composite particles. The nanoporous Pt/TiO2 composite 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.
摘要翻译:本发明提供一种制备纳米多孔Pt / TiO2复合颗粒的方法,通过上述制备方法制备的纳米多孔Pt / TiO 2复合颗粒和包含纳米多孔Pt / TiO 2复合颗粒的燃料电池。 根据本发明的纳米多孔Pt / TiO 2复合颗粒具有类似于市售Pt /炭黑的催化效果,因此可以应用于燃料电池。
摘要:
The present invention provides a method for preparing nanoporous Pt/TiO2 composite particles, nanoporous Pt/TiO2 composite particles prepared by the above preparation method, and a fuel cell comprising the nanoporous Pt/TiO2 composite particles. The nanoporous Pt/TiO2 composite 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.
摘要翻译:本发明提供一种制备纳米多孔Pt / TiO2复合颗粒的方法,通过上述制备方法制备的纳米多孔Pt / TiO 2复合颗粒和包含纳米多孔Pt / TiO 2复合颗粒的燃料电池。 根据本发明的纳米多孔Pt / TiO 2复合颗粒具有类似于市售Pt /炭黑的催化效果,因此可以应用于燃料电池。
摘要:
In accordance with one embodiment, a method of modifying the surface of silica nanopowder by a spray heating process is provided. In the method, surface characteristics of silica nanopowder are modified from hydrophilic to hydrophobic. A colloidal suspension including silica nanopowder and a surface modifier which are dissolved in ethanol is sprayed and thermally dried so that the surface characteristics of silica nanopowder are modified by the surface modifier coated on the surface of silica nanopowder. In the method, silica nanopowder surfaces are modified from hydrophilic to hydrophobic by controlling concentration and type of a surface modifier and heating temperature.
摘要:
Provided is a method of fabricating silica-titania nanoporous composite powder by controlling a pore size. In more particular, a method of fabricating silica-titania nanoporous composite powder, using a spraying and heating reactor including an ultrasonic droplet generator and a cylindrical electric furnace, comprises the steps of: generating droplets of a mixture suspension from a colloidal suspension prepared by mixing silica (SiO2) and titania (TiO2) nanopowders and organic template (PSL: polystyrene latex) powder, by the ultrasonic droplet generator of the spray-heating reactor; generating a silica-titania-organic template nanoporous composite powder having pores within the range of 20˜100 nm in size through preparing silica-titania-organic template (SiO2—TiO2-PLS) composite particles and removing the organic template while passing the mixture suspension in the cylindrical electric furnace by a carrier gas; and collecting the generated nanoporous material by a particle collector.
摘要:
A droplet generation system includes a first nozzle configuration structured to receive a liquid and a gas under pressure in a controllable feed ratio, and to merge the liquid and gas to form an intermediate stream that is a mixture of the gas and of a dispersed phase of the liquid. A second nozzle configuration is connected to receive the intermediate stream from the first nozzle configuration and has a valve mechanism with one or more controllable operating parameters to emit a stream of droplets of the liquid. The mean size of the droplets is dependent on the controllable feed ratio of the liquid and gas and the flow rate of the stream of droplets is dependent on the controllable operating parameter(s) of the valve mechanism. A corresponding method is disclosed, as is the application of the system and method to the production of nanoparticles in a thermochemical reactor.
摘要:
Provided is a method of fabricating silica-titania nanoporous composite powder by controlling a pore size. In more particular, a method of fabricating silica-titania nanoporous composite powder, using a spraying and heating reactor including an ultrasonic droplet generator and a cylindrical electric furnace, comprises the steps of: generating droplets of a mixture suspension from a colloidal suspension prepared by mixing silica (SiO2) and titania (TiO2) nanopowders and organic template (PSL: polystyrene latex) powder, by the ultrasonic droplet generator of the spray-heating reactor; generating a silica-titania-organic template nanoporous composite powder having pores within the range of 20˜100 nm in size through preparing silica-titania-organic template (SiO2—TiO2—PLS) composite particles and removing the organic template while passing the mixture suspension in the cylindrical electric furnace by a carrier gas; and collecting the generated nanoporous material by a particle collector.The present invention provides the method of fabricating silica-titania nanoporous composite powder by controlling the pore size and the mixing ratio of silica-titania.
摘要:
A droplet generation system includes a first nozzle configuration structured to receive a liquid and a gas under pressure in a controllable feed ratio, and to merge the liquid and gas to form an intermediate stream that is a mixture of the gas and of a dispersed phase of the liquid. A second nozzle configuration is connected to receive the intermediate stream from the first nozzle configuration and has a valve mechanism with one or more controllable operating parameters to emit a stream of droplets of the liquid. The mean size of the droplets is dependent on the controllable feed ratio of the liquid and gas and the flow rate of the stream of droplets is dependent on the controllable operating parameter(s) of the valve mechanism. A corresponding method is disclosed, as is the application of the system and method to the production of nanoparticles in a thermochemical reactor.
摘要:
The invention relates to a method for making silica nanoparticles using a flame reactor, which includes a droplet spray having a two-fluid nozzle and a burner of a quintuple tube structure. In this method, droplets of silicon alkoxide as liquid Si compound are sprayed through the droplet spray of the flame reactor. A flame is generated by the flow of inert gas, oxygen, hydrogen and air simultaneously into the burner of the flame reactor. The liquid Si compound is delivered through the flame of the burner to produce silica nanoparticles having a mean particle size ranging from 9 nm to 68 nm. Resultant nanoparticles are collected and recovered in a particle collector. The droplets sprayed under high pressure from a silicon alkoxide solution are directly oxidized in the flame, thereby producing spherical silica nanoparticles.
摘要:
The invention relates to a method for making silica nanoparticles using a flame reactor, which includes a droplet spray having a two-fluid nozzle and a burner of a quintuple tube structure. In this method, droplets of silicon alkoxide as liquid Si compound are sprayed through the droplet spray of the flame reactor. A flame is generated by the flow of inert gas, oxygen, hydrogen and air simultaneously into the burner of the flame reactor. The liquid Si compound is delivered through the flame of the burner to produce silica nanoparticles having a mean particle size ranging from 9 nm to 68 nm. Resultant nanoparticles are collected and recovered in a particle collector. The droplets sprayed under high pressure from a silicon alkoxide solution are directly oxidized in the flame, thereby producing spherical silica nanoparticles.