A transition metal composite hydroxide can be used as a precursor to allow a lithium transition metal composite oxide having a small and highly uniform particle diameter to be obtained. A method also is provided for producing a transition metal composite hydroxide represented by a general formula (1) MxWsAt(OH)2+, coated with a compound containing the additive element, and serving as a precursor of a positive electrode active material for nonaqueous electrolyte secondary batteries. The method includes producing a composite hydroxide particle, forming nuclei, growing a formed nucleus; and forming a coating material containing a metal oxide or hydroxide on the surfaces of composite hydroxide particles obtained through the upstream step.

A transition metal composite hydroxide can be used as a precursor to allow a lithium transition metal composite oxide having a small and highly uniform particle diameter to be obtained. A method also is provided for producing a transition metal composite hydroxide represented by a general formula (1) MxWsAt(OH)2+, coated with a compound containing the additive element, and serving as a precursor of a positive electrode active material for nonaqueous electrolyte secondary batteries. The method includes producing a composite hydroxide particle, forming nuclei, growing a formed nucleus; and forming a coating material containing a metal oxide or hydroxide on the surfaces of composite hydroxide particles obtained through the upstream step.

A cathode composition for a sodium-ion battery. The cathode composition may have the formula NaCr.sub.1-xM.sub.xO.sub.2, where M is one or more metal elements, and x is greater than 0 and less than or equal to 0.5.

A manganese nickel composite hydroxide which serves as a starting material for positive electrode active materials for secondary batteries, and the secondary battery having low resistance and high output characteristics. A manganese nickel composite hydroxide according to the present invention is represented by general formula (A) Mn.sub.1xyNi.sub.xM.sub.y(OH).sub.2+ (wherein 00.27, 0y0.05, 00.5, and M represents at least one element selected from among Mg, Al, Ca, Ba, Sr, Ti, V, Fe, Cr, Co, Cu, Zr, Nb, Mo and W), and has an SO.sub.4 content of 0.90% by weight or less, an Na content of 0.04% by weight or less, a BET specific surface area of from 40 m.sup.2/g to 70 m.sup.2/g (inclusive), and a value obtained by [(d.sub.90 -d.sub.10)/(average particle diameter)] of 0.90 or less, said value being an index indicating the expanse of the particle size distribution.

A method for forming a cathode includes milling a suspension of precursors via a micromedia mill to form a mixture of primary particles in the suspension. The precursors include one or more metal compounds. The method includes spray drying the suspension after the milling to form secondary particles. The secondary particles are agglomerations of the primary particles. The method also includes annealing the secondary particles to form a disordered rocksalt powder.

The present invention provides a layered double hydroxide with improved conductivity, a layered double hydroxide and a composite material containing the layered double hydroxide. The layered double hydroxide is represented by the general formula: [Mg.sup.2+.sub.(1-y)M1.sup.+.sub.y].sub.1-x[Al.sup.3+.sub.(1-z)M2.sup.+.sub.z].sub.x(OH).sub.2A.sup.n.sub.x/n.mH.sub.2O, wherein 0.1x0.4, 0y0.95, and 0z0.95, provided that both y and z are not 0 at the same time; =1 or 2; =2 or 3; A.sup.n is an n-valent anion, provided that n is an integer of 1 or greater; m0; M1.sup.+ is a cation of at least one substituent element selected from monovalent elements, transition metal elements, and other elements with an ionic radius greater than that of Mg.sup.2+; and M2.sup.+ is a cation of at least one element selected from divalent elements, transition metals, and other elements with an ionic radius greater than that of Al.sup.3+.

The present invention provides a positive-electrode active material for non-aqueous secondary battery comprising a sodium transition metal composite oxide represented by Formula:

Na.sub.xFe.sub.1-yM.sub.yO.sub.2, wherein 0.4x0.7, 0.25y<1.0, and M is at least one element selected from the group consisting of manganese, cobalt and nickel, the sodium transition metal composite oxide having a crystal structure substantially composed of P6.sub.3/mmc alone.

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.

Nanowires useful as heterogeneous catalysts are provided. The nanowire catalysts are useful in a variety of catalytic reactions, for example, the oxidative coupling of methane to ethylene. Related methods for use and manufacture of the same are also disclosed.

A system, method, and articles of manufacture for a surface-modified transition metal cyanide coordination compound (TMCCC) composition, an improved electrode including the composition, and a manufacturing method for the composition which may include multiple chelation species (Che_x). The composition, compound, device, and uses thereof according to A.sub.xMn.sub.(y-k)M.sup.j.sub.k[Mn.sup.m(CN).sub.(6-p-q)(NC).sub.p(Che_I).sup.r.sub.q].sub.z. CHE_GROUP (Vac).sub.(1-z).nH.sub.2O, wherein CHE_GROUP includes one or more chelation materials selected from the group consisting of (Che_I).sup.r.sub.w, (Che_II).sup.s.sub.v, and combinations thereof, and wherein 0<j4, 0k0.1, 0(p+q)6, 0<x4, 0<y1, 0<z1, 0<w0.2; 3r3; 0<v0.2; 3s3; and 0n6; wherein x+2(yk)+jk+(m+(r+1)q6)z+wr+vs=0.