A method of making a catalyst layer of a membrane electrode assembly (MEA) for a polymer electrolyte membrane fuel cell includes the step of preparing a porous buckypaper layer comprising at least one selected from the group consisting of carbon nanofibers and carbon nanotubes. Platinum group metal nanoparticles are deposited in a liquid solution on an outer surface of the buckypaper to create a platinum group metal nanoparticle buckypaper. A proton conducting electrolyte is deposited on the platinum group metal nanoparticles by electrophoretic deposition to create a proton-conducting layer on the an outer surface of the platinum nanoparticles. An additional proton-conducting layer is deposited by contacting the platinum group metal nanoparticle buckypaper with a liquid proton-conducting composition in a solvent. The platinum group metal nanoparticle buckypaper is dried to remove the solvent. A membrane electrode assembly for a polymer electrolyte membrane fuel cell is also disclosed.

A method of making a catalyst layer of a membrane electrode assembly (MEA) for a polymer electrolyte membrane fuel cell includes the step of preparing a porous buckypaper layer comprising at least one selected from the group consisting of carbon nanofibers and carbon nanotubes. Platinum group metal nanoparticles are deposited in a liquid solution on an outer surface of the buckypaper to create a platinum group metal nanoparticle buckypaper. A proton conducting electrolyte is deposited on the platinum group metal nanoparticles by electrophoretic deposition to create a proton-conducting layer on the an outer surface of the platinum nanoparticles. An additional proton-conducting layer is deposited by contacting the platinum group metal nanoparticle buckypaper with a liquid proton-conducting composition in a solvent. The platinum group metal nanoparticle buckypaper is dried to remove the solvent. A membrane electrode assembly for a polymer electrolyte membrane fuel cell is also disclosed.

By configuring a timepiece component to include an intermediate film provided on at least a portion of a surface of a base material formed by using a nonconductive first material as a main component and to include a buffer film stacked on the intermediate film and mainly composed of a second material having a tenacity higher than that of the first material, the timepiece component may be manufactured with high precision, the weight thereof may be reduced, and even when the base material is formed by using a brittle material such as silicon, the timepiece component becomes resistant to breakage and capable of exhibiting high strength when an impact is externally applied.

Graphene electrodes-based supercapacitors are in demand due to superior electrochemical characteristics. However, commercial applications have been limited by inferior electrode cycle life. A method to fabricate highly efficient supercapacitor electrodes using pristine graphene sheets vertically-stacked and electrically connected to the carbon fibers which results in vertically-aligned graphene-carbon fiber nanostructure is disclosed. The vertically-aligned graphene-carbon fiber electrode prepared by electrophoretic deposition possesses a mesoporous three-dimensional architecture which enabled faster and efficient electrolyte-ion diffusion with a specific capacitance of 333.3 F g.sup.−1. The electrodes have electrochemical cycling stability of more than 100,000 cycles with 100% capacitance retention. Apart from the electrochemical double layer charge storage, the oxygen-containing surface moieties and α-Ni(OH).sub.2 present on the graphene sheets enhance the charge storage by faradaic reactions. This enables the assembled device to provide a gravimetric energy density of 76 W h kg.sup.−1 with a 100% capacitance retention even after 1,000 bending cycles.

The invention relates to a method for coating an organic or metallic material by covalent grafting of at least one organic compound A having at least one aromatic group substituted with a diazonium function, on a surface of said material, characterized in that the material is porous or fibrillar having a geometric surface area of at least 10 cm.sup.2 of material, and in that said method includes a step of continuous imposition of a non-zero pulsed current in an intensiostatic mode on the surface of the material in order to electrochemically reduce the diazonium ion or ions. The invention further relates to the resulting composite materials and to the use of such materials for manufacturing electrodes.

The invention relates to a method for coating an organic or metallic material by covalent grafting of at least one organic compound A having at least one aromatic group substituted with a diazonium function, on a surface of said material, characterized in that the material is porous or fibrillar having a geometric surface area of at least 10 cm.sup.2 of material, and in that said method includes a step of continuous imposition of a non-zero pulsed current in an intensiostatic mode on the surface of the material in order to electrochemically reduce the diazonium ion or ions. The invention further relates to the resulting composite materials and to the use of such materials for manufacturing electrodes.

A rare earth permanent magnet is prepared by immersing a portion of a sintered magnet body of R.sup.1—Fe—B composition (wherein R.sup.1 is a rare earth element) in an electrodepositing bath of a powder dispersed in a solvent, the powder comprising an oxide, fluoride, oxyfluoride, hydride or rare earth alloy of a rare earth element, effecting electrodeposition for letting the powder deposit on a region of the surface of the magnet body, and heat treating the magnet body with the powder deposited thereon at a temperature below the sintering temperature in vacuum or in an inert gas.

A method of localized repair to a damaged thermal barrier, the method including subjecting a part coated in a damaged thermal barrier to electrophoresis treatment, the part being made of an electrically conductive material, the damaged thermal barrier including a ceramic material and presenting at least one damaged zone that is to be repaired, the part being present in an electrolyte including a suspension of particles in a liquid medium, the ceramic coating being deposited by electrophoresis in the damaged zone in order to obtain a repaired thermal barrier for use at temperatures higher than or equal to 1000° C., the particles being made of a material different from the ceramic material present in the damaged thermal barrier.

A method of localized repair to a damaged thermal barrier, the method including subjecting a part coated in a damaged thermal barrier to electrophoresis treatment, the part being made of an electrically conductive material, the damaged thermal barrier including a ceramic material and presenting at least one damaged zone that is to be repaired, the part being present in an electrolyte including a suspension of particles in a liquid medium, the ceramic coating being deposited by electrophoresis in the damaged zone in order to obtain a repaired thermal barrier for use at temperatures higher than or equal to 1000° C., the particles being made of a material different from the ceramic material present in the damaged thermal barrier.

A nanoporous metal structure is made by etching a metal alloy structure of two or more metals. Less than all of the metals are selectively removed (e.g., dissolved in solution) from the alloy in the presence of an alternating voltage profile, for example, a periodic voltage profile. The resulting nanoporous metal structure, having pore openings of about 20 nm to about 500 nm in diameter and a purity of at least about 70%, can be further treated to alter some or all of the structure, and/or to add, remove and/or modify properties thereof.