Abstract: The present invention relates to improved membrane electrode assemblies, having two electrochemically active electrodes separated by a polymer electrolyte membrane. The membrane electrode assemblies according to the instant invention contains at least one phosphoric acid-containing polymer electrolyte membrane and two gas diffusion electrodes one of each located at both sides of said membrane, each of the gas diffusion electrodes having at least one catalyst layer facing towards the membrane. At least one of the gas diffusion electrodes contains a gas diffusion medium comprising an electrically conductive macroporous layer in which the pores have a mean pore diameter in the range from 10 ?m to 30 ?m and at least one micro porous layer arranged between said gas diffusion medium and said catalyst layer facing towards the membrane having a defined pore void volume and pore hydrophobicity measured by the Cobb Titration.

Abstract: The present invention relates to improved membrane electrode assemblies, having two electrochemically active electrodes separated by a polymer electrolyte membrane. The membrane electrode assemblies according to the instant invention contains at least one phosphoric acid-containing polymer electrolyte membrane and two gas diffusion electrodes one of each located at both sides of said membrane, each of the gas diffusion electrodes having at least one catalyst layer facing towards the membrane. At least one of the gas diffusion electrodes contains a gas diffusion medium comprising an electrically conductive macroporous layer in which the pores have a mean pore diameter in the range from 10 ?m to 30 ?m and at least one micro porous layer arranged between said gas diffusion medium and said catalyst layer facing towards the membrane having a defined pore void volume and pore hydrophobicity measured by the Cobb Titration.

Abstract: A method of producing a finely divided ruthenium-platinum alloy catalyst comprising: (i) forming a mixture of platinum ?-diketone and ruthenium ?-diketone on a carbon support, (ii) both, platinum ?-diketone and ruthenium ?-diketone having a decomposition temperature within 20° C. of each other, (iii) decomposing said platinum ?-diketone and ruthenium ?-diketone on a carbon support at a temperature of at least 260° C. in the absence of a reducing agent (iv) followed by a reduction effected with a hydrogen containing gas mixture and a method from oxidizing methanol.

Abstract: A carbon-supported platinum catalyst obtained by chemical reduction of in situ-formed platinum dioxide on a carbon support and a method of production thereof.

Abstract: A gas diffusion electrode comprising an electrically conductive web, a non-catalyzed gas diffusion layer comprising at least one electroconductive filler and at least one binder, and a noble metal coating obtained by subjecting an electrically conductive web to a first ion beam having an energy not higher than 500 eV, then to a second beam having an energy of at least 500 eV, containing the ions of at least one noble metal.

Abstract: A gas diffusion electrode comprising an electrically conductive web, a non-catalyzed gas diffusion layer comprising at least one electroconductive filler and at least one binder, and a noble metal coating obtained by subjecting an electrically conductive web to a first ion beam having an energy not higher than 500 eV, then to a second beam having an energy of at least 500 eV, containing the ions of at least one noble metal.

Abstract: The instant invention relates to a platinum alloy supported electrocatalyst for gas diffusion electrode and/or in catalyst-coated membrane.

Abstract: A method for forming a noble metal coating on a gas diffusion medium substantially free of ionomeric components comprising subjecting an electrically conductive web to a first ion beam having an energy not higher than 500 eV, then to a second beam having an energy of at least 500 eV, containing the ions of at least one noble metal and electrodes provided by the method.

Abstract: A method of producing a catalyst for oxygen reduction and a gas diffusion electrode.

Abstract: A carbon-supported platinum alloy catalyst obtained by simultaneous chemical reduction of in situ-formed platinum dioxide and of at least one transition metal hydrous oxide on a carbon support.

Abstract: A binary platinum-ruthenium alloy suitable as the active component of a direct methanol fuel cell anode and use thereof in a fuel cell and the method of forming a catlyst therefrom.

Abstract: Compositions of matter according to the present invention comprise a carrier compound immobilized in or on a solid phase. The carrier compound is reactive to bind a ligand such as molecular oxygen and includes a complex formed from a transition metal ion and a multidentate organic chelate. The solid phase is substantially immiscible in or separated from a ligand-containing environment, and the compositions are utilized by contacting the immobilized carrier compounds with the ligand-containing environment. Desirably, the compositions may be maintained in an inactive state (i.e., unable to bind ligand) where the transition metal ion is separated from the chelate. By allowing the complex to form at a preselected time, premature ligand binding can be avoided.