High-temperature thermochemical energy storage materials using doped magnesium-transition metal spinel oxides are provided. -transition metal spinel oxides, such as magnesium manganese oxide (MgMn).sub.3O.sub.4, are promising candidates for high-temperature thermochemical energy storage applications. However, the use of these materials has been constrained by the limited extent of their endothermic reaction. Embodiments described herein provide for doping magnesium-transition metal spinel oxides to produce a material of low material costs and with high energy densities, creating an avenue for plausibly sized modules with high energy storing capacities.

Particulate LMFP cathode materials having high manganese contents and small amounts of dopant metals are disclosed. These cathode materials are made by milling a mixture of precursor materials in a wet or dry milling process. Preferably, off-stoichiometric amounts of starting materials are used to make the cathode materials. Unlike other high manganese LMFP materials, these cathode materials provide high specific capacities, very good cycle life and high energies even at high discharge rates.

An antimicrobial material including a substrate and an antimicrobial mixed metal oxide, mixed metal sulfide, or mixed metal oxysulfide in and/or on the substrate is described, as well as antimicrobial coating materials and coatings formed therefrom. The antimicrobial material may be constituted in an antimicrobial surface of a surface-presenting substrate, to combat transmission and spread of microbial disease, e.g., disease mediated by microbial pathogens such as bacteria, viruses, and fungi. Antimicrobial mixed metal oxide, mixed metal sulfide, or mixed metal oxysulfide as described may be contacted with microorganisms to effect inactivation thereof.

A method for preparing a zinc manganate anode material is disclosed. The method includes the following steps: (1) preparing a solution A containing a manganese ion and a solution B containing zinc alkali; (2) dispersing an adsorption carrier into the solution B; (3) using an alkali solution as a base solution and adding the solution A, the solution B and an oxidant solution to the base solution while stirring; (4) conducting a solid-liquid separation of the materials after reaction to obtain a solid; and (5) washing, drying and calcining the solid to obtain a zinc manganate anode material.

Particulate LMFP cathode materials having high manganese contents and small amounts of dopant metals are disclosed. These cathode materials are made by milling a mixture of precursor materials in a wet or dry milling process. Preferably, off-stoichiometric amounts of starting materials are used to make the cathode materials. Unlike other high manganese LMFP materials, these cathode materials provide high specific capacities, very good cycle life and high energies even at high discharge rates.

The present invention provides a carbon dioxide reduction catalyst capable of reducing carbon dioxide under mild conditions, a carbon dioxide reduction method using the carbon dioxide reduction catalyst, and a carbon dioxide reduction apparatus. A metal oxide of the present invention has a spinel-type crystal structure including a metal element A, manganese, and oxygen. The A is at least one metal element selected from the group consisting of nickel and copper, a molar composition ratio of manganese to oxygen is from 1:1.8 to 1:2.2, and a molar composition ratio of the metal element A to manganese is from 1:1.7 to 1:2.3. In an X-ray diffraction pattern obtained by X-ray diffraction measurement using a Cu-K ray, the metal oxide has an intensity ratio (I.sub.18/I.sub.37) of 0.2 or more between a peak having a 2 value in a range of from 16 to) 20 (P.sub.18) and a peak having a 2 value in a range of from 35 to 39 (P.sub.37).

An antimicrobial material including a substrate and an antimicrobial mixed metal oxide, mixed metal sulfide, or mixed metal oxysulfide in and/or on the substrate is described, as well as antimicrobial coating materials and coatings formed therefrom. The antimicrobial material may be constituted in an antimicrobial surface of a surface-presenting substrate, to combat transmission and spread of microbial disease, e.g., disease mediated by microbial pathogens such as bacteria, viruses, and fungi. Antimicrobial mixed metal oxide, mixed metal sulfide, or mixed metal oxysulfide as described may be contacted with microorganisms to effect inactivation thereof.

[Summary] A positive electrode active material is provided to contain: a solid solution lithium-containing transition metal oxide (A) represented by Li.sub.1.5[Ni.sub.aCo.sub.bMn.sub.c[Li].sub.d]O.sub.3 (where a, b, c and d satisfy the relations of a+b+c+d=1.5, 0.1<d0.4, 1.1a+b+c<1.4, 0.2a0.7 and 0<b/a<1); and a lithium-containing transition metal oxide (B) represented by LiM.sub.XMn.sub.2XO.sub.4 (where M represents Cr or Al, and x satisfies the relation of 0x<2).

A method of reducing magnetic and/or oxidic contaminants in lithium metal oxygen compounds in particle form, in order to obtain purified lithium metal oxygen compounds, by means of treatment in a grinding process and sifting process with continuous or non-continuous removal and obtaining of the purified lithium metal oxygen compound. The grinding process and sifting process are terminated prematurely before the residue amounts to less than 1% of the quantity m. The residue, containing contaminants, is discarded.

Disclosed are positive electrode active materials for a rechargeable battery, positive electrodes including the positive electrode active materials, and rechargeable lithium batteries including the positive electrode active materials. The positive electrode active material comprises first particles comprising a compound having an olivine structure, second particles comprising a compound having a spinel structure, and third particles comprising a compound having a layered structure. The first particles and the second particles constitute a main active material, and the amount of the main active material is about 80 parts by weight to about 90 parts by weight based on 100 parts by weight of the positive electrode active material.