Membrane electrode assembly comprising oxygen evolution reaction catalyst disposed in gas distribution layer (100, 700) or between gas distribution layer (100, 700 and gas dispersion layer (200, 600). Membrane electrode assemblies described herein are useful, for example, in electrochemical devices such as a fuel cell.

An electrochemical cell includes an air electrode in flow communication with a storage tank containing an aqueous solution of hydrogen peroxide, a lithium electrode, a catalyst layer in contact with the air electrode or a gas diffusion layer associated with the air electrode, and a separator layer in contact with the lithium electrode and catalyst layer. The catalyst layer includes a catalyst for two electron reversible oxygen reduction. The catalyst comprises gold, and a cobalt coordination complex or polymer thereof. The cobalt coordination complex comprises a cobalt ion chelated by a tetradentate organic chelating ligand.

It is provided a secondary zinc-air battery comprising at least two secondary zinc-air electrochemical cells, each cell comprising an air cathode that is a bifunctional air electrode (BAE); a zinc-containing anode; a free electrolyte contained in a reservoir; and a first and a second separators; wherein the zinc-containing anode is disposed between the BAE and the free electrolyte, and is separated from the BAE by the first separator and separated from the free electrolyte by the second separator, and wherein the at least two cells are assembled together in such a way that a unique electrolyte reservoir containing the free electrolyte is placed between at least two zinc anodes and thus is shared by the at least two secondary zinc-air electrochemical cells.

A composite cathode including: a cathode conductor layer including a mixed conductor; and a cathode junction layer adjacent to the cathode conductor layer, the cathode junction layer including a solid electrolyte, wherein the mixed conductor has a lithium-ion conductivity and an electrical conductivity, and wherein the solid electrolyte has a lithium-ion conductivity. In addition, the present disclosure provides a lithium-air battery including the composite cathode.

Disclosed are a reversible fuel cell oxygen electrode in which IrO.sub.2 is electrodeposited and formed on a porous carbon material and platinum is applied thereon to form a porous platinum layer, a reversible fuel cell including the same, and a method for preparing the same. According to the corresponding reversible fuel cell oxygen electrode, as the loading amounts of IrO.sub.2 and platinum used in the reversible fuel cell oxygen electrode can be lowered, it is possible to exhibit excellent reversible fuel cell performances (excellent fuel cell performance and water electrolysis performance) by improving the mass transport of water and oxygen while being capable of reducing the loading amounts of IrO.sub.2 and platinum. Further, it is possible to exhibit a good activity of a catalyst when the present disclosure is applied to a reversible fuel cell oxygen electrode and to reduce corrosion of carbon.

An electrode mixture layer composition for a nonaqueous electrolyte secondary battery contains an active material, water and a binder. The binder contains a crosslinked polymer of a monomer component including an ethylenically unsaturated carboxylic acid monomer, and a salt thereof. The crosslinked polymer is a polymer that is crosslinked with allyl methacrylate, and an amount of the allyl methacrylate used is 0.1 to 2.0 parts by weight relative to total 100 parts by weight of non-crosslinking monomers, and a content of the crosslinked polymer and salt thereof is 0.5% to 5.0% by weight of the active material.

A catalyst is provided for the two electron reduction of oxygen. The catalyst can be reversible or near-reversible. The catalyst comprises a gold and a cobalt coordination complex, i.e., N,N-bis(salicylidene)ethylene-diaminocobalt (II) (cobalt salen) or a derivative thereof. The cobalt coordination complex can be polymerized to form a film, for example, via electropolymerization, to cover a gold surface. Also provided are metal-air batteries, fuel cells, and air electrodes that comprise the catalyst, as well as methods of using the catalyst, for example, to reduce oxygen and/or produce hydrogen peroxide.

Porous materials having yolk-shell structures are described. A porous material can include an elemental sulfur nanostructure, a carbon-containing porous shell with an exterior surface and an interior surface that defines and encloses a hollow space within the interior of the shell, and a polysulfide trapping agent. The elemental sulfur nanostructure is comprised in the hollow space of the carbon-containing porous shell. Methods of making and use are also described.

A three-dimensional (3D) porous nanowire electrode can include a plurality of nanowires arranged in a 3D mesh configuration within a defined area. The diameter of each nanowire is within a range of 10 nm-1000 nm. The nanowires are sintered to each other at points of contact in the 3D mesh configuration. The 3D porous electrodes can be used in a variety of electrochemical reactor systems, such as reduction-oxidation batteries, water treatment systems, and electrochemical organic synthesis systems.

An innovative device that integrates, internally to one individual electrochemical cell, the functions of an electrolyzer, a hydrogen accumulator, and a fuel cell. The device can be recharged both electrically, by connecting it to a usual battery charger, and by way of a direct injection of gaseous hydrogen. The present device is very compact and features a reduced weight, consequently it can be advantageously used both to supply power to small-size portable electronic devices and to supply power to motors of electric vehicles.