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.

Provided is a precursor of a positive electrode active material containing, in a reduced amount, impurities which do not contribute to a charge/discharge reaction but rather corrode a firing furnace and peripheral equipment and thus having excellent battery characteristics and safety, and production method thereof. A method for producing a precursor of a positive electrode active material for nonaqueous electrolyte secondary batteries having a hollow structure or porous structure includes obtaining the precursor by washing nickel-manganese composite hydroxide particles having a particular composition ratio and a pore structure in which pores are present within the particles with an aqueous carbonate solution having a carbonate concentration of 0.1 mol/L or more.

Layered double hydroxides having a high surface area (at least 125 m.sup.2/g) and the formula (I)

[M.sup.z+.sub.1-xM.sup.y+.sub.x(OH).sub.2].sup.a+(X.sup.n-).sub.a/n.sup.+bH.sub.2O.c(AMO-solvent)(I)

wherein M and M are different and each is a charged metal cation (and must be present), z=1 or 2; y=3 or 4, 0<x<0.9, b is 0 to 10, c=0 to 10, X is an anion, n is the charge on the anion, and a=z(1x)+xy2; AMO-solvent is aqueous miscible organic solvent, may be prepared by a method which comprises a) precipitating a layered double hydroxide having the formula

[M.sup.z+.sub.1-xM.sup.y+.sub.x(OH).sub.2].sup.a+(X.sup.n-).sub.a/n.sup.+bH.sub.2O wherein M, M, z, y, x, a, b and X are as defined above from a solution containing the cations of the metals M and M and the anion X.sup.n-; b) ageing the layered double hydroxide precipitate obtained in step a) in the original solution; c) collecting, then washing the layered double hydroxide precipitate; d) dispersing the wet layered double hydroxide in an AMO solvent so as to produce a slurry of the layered double hydroxide in the solvent; e) maintaining the dispersion obtained in step d); and f) recovering and drying the layered double hydroxide.

The high surface area products have low particle size and are particularly suitable for use as catalysts, catalyst supports, sorbents and coatings.

The invention relates to electrodes that contain active materials of the formula: Na.sub.aX.sub.bM.sub.cM.sub.d(condensed polyanion).sub.e(anion).sub.f; where X is one or more of Na+, Li+ and K+; M is one or more transition metals; M is one or more non-transition metals; and where a>b; c>0; d0; e1 and f0. Such electrodes are useful in, for example, sodium ion battery applications.

Provided is a cerium-zirconium-based composite oxide having an excellent OSC, high catalytic activity, and excellent heat resistance, and also provided is a method for producing the same. The cerium-zirconium-based composite oxide comprises cerium, zirconium, and a third element other than these elements. The third element is (a) a transition metal element or (b) at least one or more elements selected from the group consisting of rare earth elements and alkaline earth metal elements. After a heat treatment at 1,000 C. to 1,100 C. for 3 hours, (1) the composite oxide has a crystal structure containing a pyrochlore phase, (2) a value of {I111/(I111+I222)}100 is 1 or more, and (3) the composite oxide has an oxygen storage capacity at 600 C. of 0.05 mmol/g or more, and an oxygen storage capacity at 750 C. of 0.3 mmol/g or more.

The present arrangement provides compounds (I) A.sub.aM.sub.m(YO4).sub.yZ.sub.z(I) that are obtained from precursors of the constituent elements by a method having steps that can include dispersion of the precursors in a liquid support having one or more ionic liquids made up of a cation and an anion the electric charges of which balance out to give a suspension of the precursors in the liquid. The suspension is heated to a temperature of 25 to 380 C. and the ionic liquid and the inorganic oxide of formula (I) are separated from the reaction of the precursors.

Please cancel the abstract of this application and replace it with the following amended abstract presented in clean form according to the procedures outlines in MPEP 714(II)(B): It is provided an alkali metal metalate compound with high magnetic exchange bias and ionic conductivity properties having the general formulae (I) A.sub.2[M.sup.1.sub.3-x M.sup.2.sub.x Z.sub.4] with A being one of Li, Na, K; M.sup.1, M.sup.2 being one or more of Cr, Mn, Fe, Co, Ni, Cu, Zn; Z being S or Se; x being 0-3, preferably 0, 0.01, 0.1, 0.5, 1, 1.5, 2, 3; whereby the compounds K.sub.2[Ni.sub.3S.sub.4], K.sub.2[Zn.sub.3S.sub.4], K.sub.2[Mn.sub.3S.sub.4], Na.sub.2[Mn.sub.3Se.sub.4] and K.sub.2[Ni.sub.3Se.sub.4] are exempted.

A sodium-ion battery includes a cathode comprising sodium; and an anode composition comprising a material having the formula: A.sub.aB.sub.bC.sub.cD.sub.dO, where A is an alkali metal, alkaline earth metal, or a combination thereof, where B is titanium, C is vanadium, D is one or more transition metal element other than titanium or vanadium, a+b+c+d1, a0, b+c>0, b0, c0, d>0, and where the material comprises a ilmenite structure, triclinic VFeO.sub.4 structure, cubic Ca.sub.5Co.sub.4(VO.sub.4).sub.6 structure, dichromate structure, orthorhombic -CoV.sub.3O.sub.8 structure, brannerite structure, thortveitite structure, orthorhombic -CrPO.sub.4 structure, or the pseudo rutile structure.

The invention relates to a chemical compound of the formula Ni.sub.bM1.sub.cM2.sub.d(O).sub.x(OH).sub.y, wherein M1 denotes at least one element from the group consisting of Fe, Co, Mg, Zn, Cu and/or mixtures thereof, M2 denotes at least one element from the group consisting of Mn, Al, B, Ca, Cr and/or mixtures thereof, wherein b0.8, c0.5, d0.5, and x is a number between 0.1 and 0.8, y is a number between 1.2 and 1.9, and x+y=2. A process for the preparation thereof, and the use thereof as a precursor for the preparation of cathode material for secondary lithium batteries are described.

Provided is a water-swelling layered double hydroxide characterized by having an organic sulfonic acid anion (A.sup.) between layers, and by being represented by the below mentioned general formula (1): Q.sub.ZR(OH).sub.2(Z+1)(A.sup.).sub.(1y)(X.sup.n).sub.y/n.mH.sub.2O . . . (1). Here, Q is a divalent metal, R is a trivalent metal, A.sup. is an organic sulfonic acid anion, m is a real number greater than 0, and z is in the range of 1.8z4.2. X.sup.n is the n-valent anion remaining without A.sup. substitution, n is 1 or 2, y represents the remaining portion of X.sup.n, and 0y<0.4.