The present invention provides a process for preparing a membrane electrode assembly in which a microporous layer is applied to a catalyst layer. Also provided are membrane electrode assemblies obtainable by applying a macroporous layer to a catalyst layer.

The present invention refers to new membrane-electrode assembly (MBA), methods of producing the same as well as fuel cell comprising said MBA.

A metal porous material according to an aspect of the present disclosure is a metal porous material in sheet form that includes a frame having a three-dimensional network configuration, wherein the frame includes an alloy including at least nickel (Ni) and chromium (Cr), the frame 11 is a solid solution with iron (Fe), the frame includes a chromium oxide (Cr.sub.2O.sub.3) layer as an outermost layer and includes a chromium carbide layer located under the chromium oxide layer, the chromium oxide layer has a thickness not less than 0.1 μm and not more than 3 μm, and the chromium carbide layer has a thickness not less than 0.1 μm and not more than 1 μm.

An object of the present invention is to provide a gas diffusion electrode that is less likely to cause damage to an electrolyte membrane or the like due to fluff in an outer peripheral portion during production of a membrane electrode assembly. The present invention provides a gas diffusion electrode including a conductive porous substrate containing carbon fibers and a microporous layer formed on a surface of the conductive porous substrate, in which the gas diffusion electrode satisfies at least one of the following (1) and (2): (1) the number of carbon fibers protruding from an edge portion by 20 μm or more when viewed from a plane surface is less than 1.0 number/cm with respect to a length of the edge portion; and (2) the number of carbon fibers that are inclined at an angle of 30° or more in an in-plane direction of the gas diffusion electrode and have lengths of 10 μm or more when viewed from a side surface of the edge portion is less than 1.0 number/cm with respect to the length of the edge portion.

Provided according to an embodiment are a carbon electrode material and a method for preparing same. The method comprises the steps: mixing a carbon precursor powder, a molding powder, and a metal precursor powder to form a mixed powder; and thermally treating the mixed powder to form a nitrogen-doped carbon composite, wherein: the molding powder includes a metal-organic framework (MOF); the carbon precursor powder is contained in an amount of 10 wt % to 20 wt % on the basis of the total mixed powder; the molding powder is contained in an amount of 50 wt % to 80 wt % on the basis of the total mixed powder; the metal precursor powder is contained in an amount of 0.1 wt % to 5 wt % on the basis of the total mixed powder; and the carbon composite has a monoatomic or nanometer-unit sized metal located therein.

The present disclosure provides a gas diffusion layer for a proton exchange membrane fuel cell. The gas diffusion layer is a graphene membrane, and graphene lamellae in the graphene membrane are arranged irregularly. The present disclosure further provides a preparation method for the gas diffusion layer, and the proton exchange membrane fuel cell including the gas diffusion layer.

Disclosed herein is a fuel-cell unit cell, at a first part of which: the fuel-cell unit cell has a bonding layer; between a first separator and an outer peripheral edge portion of a first gas diffusion layer, the bonding layer bonds the first separator and the outer peripheral edge portion together; between the first separator and an outer peripheral edge portion of a membrane-electrode assembly, the bonding layer is bonded to the outer peripheral edge portion of the membrane-electrode assembly; and between the first separator and a support frame and/or between a second separator and the support frame, the bonding layer bonds the support frame and the separator together.

A process for manufacturing a gas diffusion device includes providing a superposition of a composite layer and of an electrically conductive element, the composite layer including electrically conductive fibers and a polymerizable resin impregnating the conductive fibers, and the electrically conductive element having an open porosity between a first face and a second face. The process also includes compressing the superposition of the composite layer and of the conductive element so as to bring said conductive fibers into contact with the first face of the element, so as to make said resin flow into said element without the resin impregnating all the volume of said conductive element; and polymerizing the resin.

A membrane electrode assembly includes a cathode, an anode and a proton-conductive membrane, wherein the cathode includes a first metal-containing catalyst and a proton-conductive ionomer, the anode includes a proton-conductive ionomer, a second metal-containing catalyst that catalyzes the reaction of hydrogen to protons, and a third metal-containing catalyst that catalyzes the reaction of CO to CO.sub.2, a total mass ratio of platinum of the second catalyst and platinum of the third catalyst to a total mass ratio of metals of the second catalyst and the third catalyst, with the exception of platinum, is greater than 3:1, and the total mass per unit area of platinum of the second catalyst and platinum of the third catalyst is less than 0.4 mg/cm.sup.2.

Disclosed are a positive electrode for lithium air batteries with excellent stability, a method of manufacturing the same, and a lithium air battery including the same, and a lithium air battery with improved stability by including the positive electrode. The positive electrode may include a conductive material and an ionic liquid such that the process of manufacturing the lithium air battery may be simplified, and the stability of the lithium air battery may be further improved as the result of inhibition of side reactions.