A method for operating a metal-hydrogen battery includes monitoring an indicator of degeneration of the metal-hydrogen battery during normal cycles of discharge and charge; determining whether the energy efficiency of the metal-hydrogen battery during normal cycles of discharge and charge is decayed based on the indicator; and in response to determining that the metal-hydrogen battery during normal cycles of discharge and charge is decayed due to oxidation, regenerating the metal-hydrogen battery.

Aspects of this disclosure pertain to catalyst compositions that include electrically conductive support particles; and metal catalyst particles attached to the electrically conductive support particles. The catalyst compositions may be used in cathodes of carbon oxide reduction electrolyzers.

A redox ion exchange membrane may include an electrically-conductive material; and redox-active materials associated with that material, the redox-active materials having reversible oxidation and reduction properties. The redox-active materials may be inorganic nanostructures on the electrically-conductive material. A hydrogen production device and a fuel cell device may include such a redox ion exchange membrane positioned between the cathode and anode. A method of producing hydrogen gas may include providing a cathode, an anode, and a redox ion exchange membrane positioned between the cathode and the anode, and applying electrical power to the cathode and the anode; where that applying causes simultaneous reciprocal reduction and oxidation reactions on opposite sides of the redox ion exchange membrane, such that H+ is released on one side of the redox ion exchange membrane

The present invention inexpensively provides an electrode material for a fuel electrode, the electrode material having CO.sub.2 resistance and being capable of forming a fuel cell having high electricity generation performance. An electrode material for a fuel electrode, the electrode material constituting a fuel electrode of a fuel cell including a proton-conductive solid electrolyte layer, includes a perovskite-type solid electrolyte component and a nickel (Ni) catalyst component, in which the solid electrolyte component includes a barium component, a zirconium component, a cerium component, and a yttrium component, and the mixture ratio of the zirconium component to the cerium component in the solid electrolyte component is set to be 1:7 to 7:1 in terms of molar ratio.

Embodiments of the invention include fuel cells incorporating sheets and/or powders of silica fibers and methods for producing such devices. The silica fibers may be formed via electrospinning of a sol gel produced with a silicon alkoxide reagent, such as tetraethyl ortho silicate, alcohol solvent, and an acid catalyst.

Methods of forming a metal-alloy graphene nanocomposites are provided. The methods include providing a graphene substrate and forming a conducting polymer layer on a first major surface of the graphene substrate. The methods also include pyrolyzing the conducting polymer layer to form a nitrogen-doped graphene substrate and dispersing a plurality of metal-alloy nanoparticles on a first surface of the nitrogen-doped graphene substrate to form the nanocomposite.

Compositions comprised of a tin film, coated by a shell of less than 50 nm thick made of palladium and tin in a molar ratio ranging from 1:4 to 3:1, respectively, are disclosed. Uses of the compositions as an electro-catalyst e.g., in a fuel cell, and particularly for the oxidation of various materials are also disclosed.

A catalyst carrier, an electrode catalyst, an electrode including the catalyst, a membrane electrode assembly including the electrode, and a fuel cell including the membrane electrode assembly. The catalyst carrier includes a carbon material having a chain structure including a chain of carbon particles and an alumina-carbon composite particle in which a carbon particle encloses an alumina particle, the alumina-carbon composite particle is contained in the carbon material, and the catalyst carrier has a BET specific surface area of 450 to 1100 m.sup.2/g.

A carrier-nanoparticle complex, a catalyst including the same, an electrochemical cell including the catalyst, and a method for preparing a carrier-nanoparticle complex.

A method for producing a catalyst supporting a metal or an alloy on a support, including: independently controlling a temperature of a first supercritical fluid to be first temperature, the first supercritical fluid containing a precursor of the metal or precursor of the alloy that is dissolved in a supercritical fluid; independently controlling a temperature of the support to be a second temperature higher than the temperature of the first supercritical fluid; and supplying the first supercritical fluid controlled to the first temperature to the support, to cause the metal or the alloy to be supported on the support.