A novel polyfluorene-based ionomer, an anion exchange membrane, a method for preparing the polyfluorene-based ionomer, and a method for fabricating the anion exchange membrane are proposed. The polyfluorene-based ionomer contains no aryl ether bonds in the polymer backbone and includes piperidinium groups incorporated into the repeating units. The anion exchange membrane is fabricated from the polyfluorene-based ionomer. The anion exchange membrane has good thermal and chemical stability, excellent mechanical properties, and high ion conductivity. Due to these advantages, the anion exchange membrane can be applied as a membrane for an alkaline fuel cell and to a binder for an alkaline fuel cell or water electrolysis.

A biological cathode and biological battery system for converting carbon feedstock into organic chemicals and producing electrical current is described. The method involves a biological battery system comprising of a reaction vessel and biological cathode electrode. The organic chemicals are processed in a space having at least one anode and at least one cathode with cathode electrode having biologically active material adjacent to at least one layer of the cathode electrode. The material can be a gel, liquid, or solid. This system can be carried out to process organic waste in an environmentally friendly manner.

Provided are a method for producing a liquid composition which is capable of eliminating clouding of a liquid with cerium (IV) hydroxide particles in a relatively short time, and methods for producing a polymer electrolyte membrane, a catalyst layer and a membrane/electrode assembly, each having excellent durability, in a relatively short time. A method for producing a liquid composition containing a fluoropolymer having sulfonic acid groups, trivalent cerium ions and water, which comprises (1) irradiating a solution containing at least one cerium compound selected from the group consisting of cerium carbonate, cerium hydroxide and cerium oxide, the fluoropolymer and the water, with light at least partially in a wavelength region from 300 to 400 nm so that the ultraviolet irradiance on the surface of the solution is at least 0.1 mW/cm.sup.2 or (2) adding a reducing agent to a solution containing at least one cerium compound selected from the group consisting of cerium carbonate, cerium hydroxide and cerium oxide, the fluoropolymer and the water.

A non-aqueous fuel cell catalyst includes a carbon support medium; a coating layer comprising a proton-conducting polymer including a phosphoric acid group coated on a surface of the carbon support medium; and a support member comprising platinum or a platinum alloy supported on the coating layer.

This anode catalyst layer for a fuel cell contains electrode catalyst particles, a carbon carrier on which the electrode catalyst particles are loaded, water electrolysis catalyst particles, a proton-conducting binder, and graphitized carbon. The graphitized carbon has a bulk density of 0.50/cm.sup.3 or less.

To provide a membrane electrode assembly capable of forming a fuel cell excellent in power generation efficiency, and a polymer electrolyte fuel cell. The membrane electrode assembly of the present invention comprises an anode having a catalyst layer containing a proton-conducting polymer and a catalyst, a cathode having a catalyst layer containing a proton-conducting polymer and a catalyst, and a solid polymer electrolyte membrane disposed between the anode and the cathode, wherein the proton-conducting polymer contained in the catalyst layer of at least one of the anode and the cathode, is a polymer (H) having a cyclic ether structural unit and an ion exchange group, and the solid polymer electrolyte membrane contains a fluorinated polymer (S) having an ion exchange group; and the thickness of the solid polymer electrolyte membrane is from 5 to 15 μm, and the ratio of the content M1 [mol %] of the cyclic ether structure unit to the thickness T1 [μm] of the solid polymer electrolyte membrane is 4.5 or more.

Disclosed are a manufacturing method of a membrane electrode assembly capable of increasing the interfacial adhesion between a polymer electrolyte membrane and a catalyst layer, improving substance delivery and performance, and enhancing hydrogen permeation resistance or oxygen permeability; a membrane electrode assembly manufactured thereby; and a fuel cell comprising the membrane electrode assembly. The manufacturing method of the present invention comprises the steps of: adding a catalyst and a first ionomer to a solvent and dispersing the same, thereby producing a dispersed mixture; adding a second ionomer to the dispersed mixture, thereby producing a coating composition; and applying the coating composition directly onto at least one side of the polymer electrolyte membrane.

Provided here are ion conducting materials including one or more macrocycles, and either one or more pendant groups or one or more backbone repeat units. The ion conducting materials exhibit distinctly high ion conductivity in thin film and bulk membrane applications, and further exhibit one or more of ion permselectivity, mechanical strength, self-assembly, stacking, and gating behavior. Further provided are methods for preparation and methods for use of the ion conducting materials.

A coated electrode assembly (CEA) comprising: i) a gas diffusion layer (GDE); and ii) a coating. The GDE comprises a gas diffusion layer (GDL) and a catalyst layer. The catalyst layer is disposed between the coating and the GDL. The catalyst layer comprises a hydrophobic polymer and/or an ionomeric polymer and the coating comprises a hydrophobic polymer and/or an ionomeric polymer. A method for making a CEA is provided. The CEA may have improved performance and stability compared to a membrane electrode assembly (MEA).

A catalyst structure includes: (1) a substrate; (2) a catalyst layer on the substrate; and (3) an adhesion layer disposed between the substrate and the catalyst layer. In some implementations, an average thickness of the adhesion layer is about 1 nm or less. In some implementations, a material of the catalyst layer at least partially extends into a region of the adhesion layer. In some implementations, the catalyst layer is characterized by a lattice strain imparted by the adhesion layer.