Abstract:
A thermoelectric material has a microstructure deformed by cryogenic impact. When the cryogenic impact is applied to the thermoelectric material, defects are induced in the thermoelectric material, and such defects increase phonon scattering, which results in enhanced figure of merit.
Abstract:
An electrode catalyst including two or more metal components used in an anode and/or a cathode of a proton exchange membrane fuel cell (PEMFC) or a direct methanol fuel cell (DMFC), a method of preparing the same, and a fuel cell including the electrode catalyst. The electrode catalyst includes an active Pt-based metal and an inactive La-based metal. By including the inactive metal component in the electrode catalyst, in addition to the active Pt-based metal component, higher catalyst activity can be obtained, and the amount of the expensive Pt-based metal can be decreased so that the fuel cell can be produced at relatively low costs. In addition, the active Pt-based metal and the inactive La-based metal are uniformly distributed so that agglomeration of the active Pt-based metal can be blocked (or prevented) and thus the catalyst activity can be maintained constant for a relatively long period of time.
Abstract:
A method of growing carbon nanotubes and a method of manufacturing a field emission device using the same is provided. The method of growing carbon nanotubes includes steps of preparing a substrate, forming a catalyst metal layer on the substrate to promote growing of carbon nanotubes, forming an inactivation layer on the catalyst metal layer to reduce the activity of the catalyst metal layer, and growing carbon nanotubes on a surface of the catalyst metal layer. Because the inactivation layer partially covers the catalyst metal layer, carbon nanotubes are grown on a portion of the catalyst metal layer that is not covered by the inactivation layer. Thus, density of the carbon nanotubes can be controlled. This method for growing carbon nanotubes can be used to make an emitter of a field emission device. The field emission device having carbon nanotube emitter made of this method has superior electron emission characteristics.
Abstract:
A bulk thermoelectric material having a structure in which migration of carriers is not inhibited but phonons are scattered is described. The bulk thermoelectric material includes: a bulk crystalline thermoelectric material matrix; and nanoparticles coated with a conductive material within the thermoelectric material matrix.
Abstract:
A method of fabricating a phase change RAM (PRAM) having a fullerene layer is provided. The method of fabricating the PRAM may include forming a bottom electrode, forming an interlayer dielectric film covering the bottom electrode, and forming a bottom electrode contact hole exposing a portion of the bottom electrode in the interlayer dielectric film, forming a bottom electrode contact plug by filling the bottom electrode contact hole with a plug material, forming a fullerene layer on a region including at least an upper surface of the bottom electrode contact plug and sequentially stacking a phase change layer and an upper electrode on the fullerene layer. The method may further include forming a switching device on a substrate and a bottom electrode connected to the switching device, forming an interlayer dielectric film covering the bottom electrode and forming a bottom electrode contact hole exposing a portion of the bottom electrode in the interlayer dielectric film.
Abstract:
The present invention is related to a lithium anode, a method of the manufacturing the same and a battery using the anode. The lithium anode comprises a metal layer (or alloy layer) that is inert to lithium and a metal layer (or alloy layer) that is reactive with lithium. The two layers may form a temporary protective layer on the lithium surface, thus providing a smooth surface. By obtaining the smooth surface, an upper polymer layer and an inorganic layer may be deposited without any difficulty and the adhesive force may be strong. Thus, the lithium anode according to the present invention has superior cycling characteristics and improved storage characteristics.
Abstract:
A rechargeable lithium battery includes a positive electrode having a positive active material to reversibly intercalate and deintercalate lithium ions, a negative electrode having a negative active material, and an electrolyte, wherein an arithmetic mean Ra of a surface roughness of the positive electrode is 155 to 419 nm, and an arithmetic mean Ra of a surface roughness of the negative electrode is 183 to 1159 nm after the rechargeable lithium battery is charged and discharged.
Abstract:
An organic electrolytic solution for a lithium-sulfur battery that provides high discharge capacity and longer cycle life to the battery, and a lithium-sulfur battery including the organic electrolytic solution are provided. The electrolytic solution includes a lithium salt, an organic solvent, and further a compound represented by Formula (I):