Methods of forming spinel ferrite nanoparticles containing a chromium-substituted copper ferrite as well as properties (e.g. particle size, crystallite size, pore size, surface area) of these spinel ferrite nanoparticles are described. Methods of preventing or reducing microbe growth on a surface by applying these spinel ferrite nanoparticles onto the surface in the form of a suspension or an antimicrobial product are also described.

Methods of forming spinel ferrite nanoparticles containing a chromium-substituted copper ferrite as well as properties (e.g. particle size, crystallite size, pore size, surface area) of these spinel ferrite nanoparticles are described. Methods of preventing or reducing microbe growth on a surface by applying these spinel ferrite nanoparticles onto the surface in the form of a suspension or an antimicrobial product are also described.

In an aspect, a multiphase ferrite comprises a Co.sub.2W phase that is optionally doped with Ru; a CFO phase having the formula Me.sub.r“Co.sub.1−rFe.sub.2+zO.sub.4, wherein Me” is at least one of Ni, Zn, or Mg, r is 0 to 0.5, and z is −0.5 to 6 0.5; and a CoRu-BaM phase having the formula BaCo.sub.x+yRu.sub.yFe.sub.12−(2/3)x−2yO.sub.19, wherein x is 0 to 2, y is 0.01 to 2; and the Ba can be partially replaced by at least one of Sr or Ca. In another aspect, a composite can comprise a polymer and the multiphase ferrite. In yet another aspect, a method of making a multiphase ferrite can comprise mixing and grinding a CoRu-BaM phase ferrite and a CFO phase ferrite to form a mixture; and sintering the mixture in an oxygen atmosphere to form the multiphase ferrite.

Disclosed herein are doped perovskite oxides. The doped perovskite oxides may be used as a cathode material in an electrochemical cell to electrochemically generate ammonia from N.sub.2. The doped perovskite oxides may be combined with nitride compounds, for instance iron nitride, to further increase the efficiency of the ammonia production.

A process for preparing a stable Li.sub.xMn.sub.2-yMe.sub.yO.sub.4-zCl.sub.z material with a MO.sub.b or MMn.sub.aO.sub.b charge transfer catalyst coating is provided, where Me is Fe, Co, or Ni and M is Bi, As, or Sb. In addition, a Li.sub.xMn.sub.2-yMe.sub.yO.sub.4-zCl.sub.z material with a MO.sub.b or MMn.sub.aO.sub.b charge transfer catalyst coating is provided. Furthermore, a lithium or lithium ion rechargeable electrochemical cell is provided, which includes a cathode material (in a positive electrode) containing a Li.sub.xMn.sub.2-yMe.sub.yO.sub.4-zCl.sub.z material with a MO.sub.b or MMn.sub.aO.sub.b charge transfer catalyst coating.

The present invention is a lithium-phosphorus-based composite oxide/carbon composite used for a positive electrode active material of an electrochemical device, including lithium-phosphorus-based composite oxide with the surface being coated with carbon, wherein the lithium-phosphorus-based composite oxide/carbon composite has elutable fluoride ions, which are eluted to an elute from the composite dispersed to ultrapure water, in a mass ratio of 500 ppm or more and 15000 ppm or less in comparison with the lithium-phosphorus-based composite oxide/carbon composite, and the lithium-phosphorus-based composite oxide has a composition of the following general formula (1):

Li.sub.1-xFe.sub.1-zM.sub.zPO.sub.4-aF.sub.a(−0.1≦x<1,0≦z≦1,0≦a≦4)  (1)

(wherein, M represents one or more kinds of metal element selected from the group of Mn, Ni, Co, V, Cr, Al, Nb, Ti, Cu, and Zn). This provides a lithium-phosphorus-based composite oxide/carbon composite that gives higher charge/discharge capacity when it is used as a positive electrode active material of an electrochemical device even though a trivalent-containing raw material is used.

A mixed conductor represented by Formula 1:
A.sub.4±xTi.sub.5−yG.sub.zO.sub.12−δ  Formula 1 wherein, in Formula 1, A is a monovalent cation, G is at least one of a monovalent cation, a divalent cation, a trivalent cation, a tetravalent cation, a pentavalent cation, or a hexavalent cation, with the proviso that G is not Ti or Cr, wherein 0<x<2, 0.3<y<5, 0<z<5, and 0<δ≤3.

Provided is a new 5 V-class spinel-type lithium-manganese-containing composite oxide capable of achieving both the expansion of a high potential capacity region and the suppression of gas generation. Proposed is the spinel-type lithium-manganese-containing composite oxide comprising Li, Mn, O and two or more other elements, and having an operating potential of 4.5 V or more at a metal Li reference potential, wherein a peak is present in a range of 14.0 to 16.5° at 2θ, in an X-ray diffraction pattern measured by a powder X-ray diffractometer (XRD) using CuKα1 ray.

Provided is a new 5 V class spinel-type lithium manganese-containing composite oxide which enables the expansion of a high potential capacity region and the suppression of gas generation. The 5 V class spinel-type lithium manganese-containing composite oxide has an operating potential of 4.5 V or more at a metal Li reference potential, and contains Li, Mn, O and two or more other elements. The spinel-type lithium manganese-containing composite oxide is characterized in that, in an electronic diffraction image from a transmission electron microscope (TEM), a diffraction spot observed in the Fd-3m structure as well as a diffraction spot not observed in the Fd-3m structure are confirmed.

A method for making lithium iron phosphate is provided. A lithium chemical compound, a ferrous chemical compound, and a phosphate-radical chemical compound are mixed in an organic solvent to form a mixture. The mixture is solvothermal reacted in a solvothermal reactor at a predetermined temperature. A protective gas is introduced into the solvothermal reactor during the solvothermal reaction to increase a pressure in the solvothermal reactor to a level higher than a self-generated pressure of the solvothermal reaction.