There is provided a method of manufacturing an electrode catalyst layer for fuel cell. This manufacturing method comprises: (a) separating an ionomer solution by centrifugation into a supernatant that includes only an ionomer as a low molecular-weight component in the ionomer solution and a sediment including an ionomer as a high molecular-weight component having a higher molecular weight than that of the low molecular-weight component included in the supernatant; (b) using the ionomer included in the sediment as an ionomer for electrode catalyst layer and producing a catalyst ink that includes catalyst-supported particles with a catalyst metal supported thereon, a solvent and the ionomer for electrode catalyst layer; and (c) using the catalyst ink to form an electrode catalyst layer.

A method of preparing a metal nanoparticle on a surface includes subjecting a metal source to a temperature and a pressure in a carrier gas selected to provide a vapor metal species at a vapor pressure in the range of about 10.sup.4 to about 10.sup.11 atm; contacting the vapor metal species with a heated substrate; and depositing the metal as a nanoparticle on the substrate.

An electrode for use in an electrochemical cell, especially a zinc-bromine flow battery or a hydrogen/bromine flow battery, and methods for manufacturing and using the electrode is provided. The electrode has a metal substrate and a catalytic coating applied onto the substrate wherein the catalytic coating has a Ru-rich mixture of ruthenium and having 70-80 mol % Ru, 1-5 mol % Pt and 17-25 mol % Ir. The catalytic coating composition exhibits a surprisingly high voltage efficiency and operating lifetime despite its relatively low Ir/Ru and Pt/Ru ratios. The underlying metal substrate is for example a porous Ti layer or a layer with titanium suboxides Ti.sub.xO.sub.y.

A catalyst layer, includes: a carrier; metal particles located over the carrier; an underlayer located on the carrier; and an ionomer-based layer located over the underlayer, wherein the underlayer includes a polymer material, and covers at least parts of the metal particles, and the ionomer-based layer includes a proton-conducting resin. A fuel cell electrode includes the catalyst layer, and a fuel cell including the above catalyst layer. A method for producing a catalyst layer, includes: bringing at least one first solution including a polymer material into contact with a metal-particle-supported carrier to form an underlayer; and bringing a second solution including a proton-conducting resin into contact with the metal-particle-supported carrier to coat said metal-particle-supported carrier with the proton-conducting resin.

A gas detector includes an electrochemical gas sensor. The sensor includes a plurality of electrodes. At least one of the electrodes is formed of a catalyst/binder slurry which is halftone printed onto a substrate. The composite printed element and substrate are sintered to form the electrode.

An electrically conductive member of the present disclosure includes a base member containing chromium (Cr), and a first layer provided on a surface of the base member and containing chromium(III) oxide (Cr.sub.2O.sub.3). The first layer also contains titanium (Ti).

There is provided a process for the manufacture of a membrane electrode assembly, a membrane electrode assembly obtainable by such a process, and a fuel cell comprising such a membrane electrode assembly. The electrode is provided by applying a layer of a first electrode first composition on an electrolyte membrane and a layer of a first electrode second composition to the same side of the electrolyte membrane as the first electrode first composition and then heating. The weight ratio of ion exchange material to catalyst in the first electrode first composition is greater than the weight ratio of ion exchange material to first catalyst in the first electrode second composition.

Disclosed herein is an electrode drying method for drying a plurality of electrodes in the state in which the electrodes are stacked, the electrode drying method including interposing a hygroscopic film between adjacent ones of the electrodes and drying the electrodes in the state in which the hygroscopic film is interposed between the electrodes, wherein at least one of the surfaces of the hygroscopic film that faces the electrodes has an uneven structure, or an electrode drying method for drying an electrode sheet in the state in which the electrode sheet is wound, the electrode drying method including winding the electrode sheet with a hygroscopic film and drying the electrode sheet in the state in which the hygroscopic film is interposed between overlapping portions of the electrode sheet, wherein at least one of the surfaces of the hygroscopic film that is disposed opposite the electrode sheet has an uneven structure.

The present invention provides a method of preparing an electrocatalyst ink, the method comprising a step of contacting a dispersion with a separation material.

Disclosed are an electrolyte membrane of a membrane-electrode assembly including an electronic insulation layer, which greatly improves the durability of the electrolyte membrane, and a method of preparing the same. The electrolyte membrane includes an ion exchange layer and an electronic insulation layer provided on the ion exchange layer, and the electronic insulation layer includes one or more catalyst complexes, and a second ionomer. Particularly, each of the one or more catalyst complex includes a catalyst particle and a first ionomer coated on the entirety or a portion of the surface of the catalyst particle, and the one or more catalyst complexes are dispersed the second ionomer.