An electrocatalyst for the production of hydrogen from water includes a pyrochlore compound with a composition or chemical formula of RE.sub.2(Ru).sub.2xM.sub.2-2xO.sub.7, RE.sub.2(Ir).sub.2xM.sub.2-2xO.sub.7or RE.sub.2(Ir,Ru).sub.2xM.sub.2-2xO.sub.7, where RE is a rare earth element, M is an alkali metal, alkaline carth metal, transition metal, post-transition metal, Ge, or Sb, and x is less than 1.0 and greater than 0.0.

Homogeneous water oxidation catalysts (WOCs) for the oxidation of water to produce hydrogen ions and oxygen, and methods of making and using thereof are described herein. In a preferred embodiment, the WOC is a polyoxometalate WOC which is hydrolytically stable, oxidatively stable, and thermally stable. The WOC oxidized waters in the presence of an oxidant. The oxidant can be generated photochemically, using light, such as sunlight, or electrochemically using a positively biased electrode. The hydrogen ions are subsequently reduced to form hydrogen gas, for example, using a hydrogen evolution catalyst (HEC). The hydrogen gas can be used as a fuel in combustion reactions and/or in hydrogen fuel cells. The catalysts described herein exhibit higher turn over numbers, faster turn over frequencies, and/or higher oxygen yields than prior art catalysts.

This invention concerns a tungsten-containing material, the application thereof and a preparation method thereof. Tungsten-containing materials can be used as electrochemical energy storage materials, fuel cell electrolytes and chemical catalyst materials. Tungsten-containing materials include tungsten oxide and tungsten oxide hydrate, doped tungsten oxides and doped tungsten oxide hydrates, tungsten oxide composites, and tungsten oxide hydrate composites.

Provided is a layered alkali iridate and a layered iridic acid to be used for producing iridium oxide nanosheets, and an iridium oxide nanosheet. A layered alkali iridate with composition of M.sub.xIrO.sub.y.nH.sub.2O (where M is a monovalent metal, x is 0.1 to 0.5, y is 1.5 to 2.5, and n is 0.5 to 1.5), wherein M.sub.xIrO.sub.y.nH.sub.2O has a layered structure. The M is potassium, and the layered alkali iridate has diffraction peaks at 2 diffraction angles of 13.0 and 26.0. A layered iridic acid with a composition of H.sub.xIrO.sub.y.nH.sub.2O (where x is 0.1 to 0.5, y is 1.5 to 2.5, and n is 0 to 1), wherein H.sub.xIrO.sub.y.nH.sub.2O has a layered structure. This layered iridic acid has diffraction peaks at 2 diffraction angles of 12.3 and 24.6. A single crystalline iridium oxide nanosheet having a thickness of 3 nm or less.

A method of manufacturing a multi-layered film at least includes: a step A of forming an electroconductive layer on a substrate; a step B of forming a seed layer so as to coat the electroconductive layer; and a step C of forming a dielectric layer so as to coat the seed layer. In the step B, a compound including strontium (Sr), ruthenium (Ru), and oxygen (O) is formed as the seed layer by a sputtering method. In the step C, where a substrate temperature is defined by Td when the dielectric layer is formed, 560 C.Td720 C. is determined.

Homogeneous water oxidation catalysts (WOCs) for the oxidation of water to produce hydrogen ions and oxygen, and methods of making and using thereof are described herein. In a preferred embodiment, the WOC is a polyoxometalate WOC which is hydrolytically stable, oxidatively stable, and thermally stable. The WOC oxidized waters in the presence of an oxidant. The oxidant can be generated photochemically, using light, such as sunlight, or electrochemically using a positively biased electrode. The hydrogen ions are subsequently reduced to form hydrogen gas, for example, using a hydrogen evolution catalyst (HEC). The hydrogen gas can be used as a fuel in combustion reactions and/or in hydrogen fuel cells. The catalysts described herein exhibit higher turn over numbers, faster turn over frequencies, and/or higher oxygen yields than prior art catalysts.

A mercury-based compound is in powder form and has the general chemical formula: M1.sub.aX.sub.b, where M1 is Hg, MxcMyd or a combination thereof, with Mx being Hg and My being an arbitrary element; wherein X is chloride, bromide, fluoride, iodide, sulphate nitrate or a combination thereof, wherein a, b, c and d are numbers between 0.1 and 10, wherein particles of the powder have a minimum average dimension of width of at least 50 nm and a maximum average dimension of width of at most 20 m, and wherein the mercury-based compound is paramagnetic and is present in an excited state.

To provide a manganese-iridium composite oxide, a manganese-iridium composite oxide and a manganese-iridium composite oxide electrode material, having high catalytic activity produced at low cost, to be used as an anode catalyst for oxygen evolution in water electrolysis, and their production methods. A manganese-iridium composite oxide, which has an iridium metal content ratio (iridium/(manganese+iridium)) of 0.1 atomic % or more and 30 atomic % or less, and has interplanar spacings of at least 0.2430.002 nm, 0.2140.002 nm, 0.1650.002 nm, 0.1400.002 nm, and a manganese-iridium composite oxide electrode material comprising an electrically conductive substrate constituted by fibers at least part of which are covered with the above manganese-iridium composite oxide.

Disclosed herein are a positive electrode active material including at least one selected from among compounds represented by Formula 1 below and a lithium secondary battery including the same that is capable of improving lifetime characteristics and rate characteristics while exhibiting excellent safety: xLi.sub.2M.sub.yMn.sub.(1-y)O.sub.3-zA.sub.z*(1x)LiMO.sub.2-zA.sub.z (1), where M is at least one element selected from a group consisting of Ru, Mo, Nb, Te, Re, Ir, Pt, Cr, S, W, Os, and Po, M is at least one element selected from a group consisting of Ni, Ti, Co, Al, Mn, Fe, Mg, B, Cr, Zr, Zn, and second row transition metals, A and A are each independently a negative monovalent or divalent anion, and 0<x<1, 0.3<y<1, 0z<0.5, and 0z<0.5.

A particulate inorganic material equipped with elemental silver and elemental ruthenium, said inorganic material having an average particle size (d50) in the range of 50 nm to 40 m and a BET surface area in the range of 1 to 1600 m.sup.2/g. The inorganic material as such is selected from the group consisting of aluminum nitride, titanium nitride, silicon nitride, corundum, titanium dioxide in the form of anatase, titanium dioxide in the form of rutile, pyrogenic silica, precipitated silica, sodium aluminum silicate, zirconium silicate, zeolite, hydrotalcite and gamma-aluminum oxide hydroxide.