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.

The present invention concerns specific new compounds of formula Li.sub.(2x)Na.sub.(x)MO.sub.(2y/2)F.sub.(1+y) (where 0x0.2 and 0.6y0,8 and M is a transition metal), cathode material comprising the new compounds, batteries and lithium-cells comprising said new compound or cathode material, a process for the production of the new compound and their use.

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.

A proton conducting ceramic membrane comprising a conducting layer, wherein said conducting layer comprises a mixture of a rare-earth tungstate as herein defined and a mixed metal oxide as herein defined. The invention also relates to a reactor comprising said membrane and the use of said membrane in a dehydrogenation process.

The present invention provides a positive electrode active material for secondary battery and a secondary battery including the same. The positive electrode active material includes a core including a lithium composite metal oxide of Formula 1 below, a first surface-treated layer positioned on the surface of the core and including a lithium oxide of Formula 2 below, and a second surface treated layer positioned on the core or the first surface-treated layer and including a lithium compound of Formula 3. Thus, the present invention can improve capacity characteristics and output characteristics of a battery and also reduce the generation of gas,

Li.sub.aNi.sub.1-x-yCo.sub.xM1.sub.yM3.sub.zM2.sub.wO.sub.2 [Formula 1]

Li.sub.mM4O.sub.(m+n)/2 [Formula 2]

Li.sub.pM5.sub.qA.sub.r [Formula 3]

(in formulae 1 to 3, A, M1 to M5, a, x, y, z, w, m, n, p, and q are the same as those defined in the specification).

The present disclosure provides a metal compound. The metal compound is represented by a formula (I): Cu.sub.2A.sub.?B.sub.2-?O.sub.4-? (I). A contains at least one element selected from the groups 6 and 8 of the periodic table. B contains at least one element selected from the group 13 of the periodic table, 0<?<2, and 0<?<1.5. Polymer article containing the metal compound and method for preparing the polymer article as well as selective metallization of a surface of the polymer article are also provided. In addition, the present disclosure provides an ink composition and the selective metallization for a surface of the insulative substrate using the ink composition.

A magnetic hydrotalcite composite which is useful in fields such as wastewater treatment, ultraviolet absorption, electromagnetic wave absorption and acid gas absorption, and a production method thereof. The magnetic hydrotalcite composite comprises an inner layer and an outer layer, in which the inner layer is made of a hydrotalcite compound and the outer layer is made of a ferrite compound.

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.

The invention relates to electrodes comprising a mixed niobium oxide as an active electrode material. The electrodes may be used in metal-ion batteries such as lithium-ion batteries. The mixed niobium oxide may have the formula M.sup.I.sub.x-uM.sup.y.sub.(x/(5-y))M.sup.V.sub.zNb.sub.100-(x/(5-y))-zO.sub.250-u/2, wherein: M.sup.I is a cation having an oxidation state of 1; M.sup.y is a cation having an average oxidation state of y; M.sup.V is a cation having an average oxidation state of 5; 1y4; 0.5x6; 0z10; 0u5; x>u.

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.