The invention relates to methods for producing coloured materials with the use of metal nanoparticles of gold, copper or silver, to said coloured materials, and to the uses of same in various applications.

A magnetoplumbite-type hexagonal ferrite powder containing a powder of a magnetoplumbite-type hexagonal ferrite represented by Formula (1) and a powder of a compound represented by Formula (2), in which a magnetic field strength Hα, which corresponds to 90% of a magnetization quantity obtained in a case where an external magnetic field of 50 kOe is applied, satisfies 19 kOe≤Hα≤28 kOe, a radio wave absorber, and a method of controlling resonance frequency of a magnetoplumbite-type hexagonal ferrite powder are provided. In Formula (1), A represents at least one metal element selected from the group consisting of Sr, Ba, Ca, and Pb, and x satisfies 1.5≤x≤8.0. In Formula (2), A.sup.a represents at least one metal element selected from the group consisting of Sr, Ba, Ca, and Pb.

AFe.sub.(12-x)Al.sub.xO.sub.19  Formula (1)

A.sup.aAl.sub.2O.sub.4  Formula (2)

The present disclosure provides a positive electrode active material which can impart an excellent low temperature output characteristic to a nonaqueous electrolyte secondary battery, and can suppress an increase in resistance after cycle charging and discharging. The positive electrode active material herein disclosed includes a core part including a lithium transition metal composite oxide, and a coating part including a titanium-containing compound on at least a partial surface of the core part. The coating part includes brookite type TiO.sub.2 and a lithium titanium (LiTi) composite oxide including lithium (Li) and titanium (Ti) as titanium-containing compounds, and at least part of titanium (Ti) of the titanium-containing compound is incorporated in a solid solution in the surface of the core part.

Bilayer structured hydrated Ca—V oxide is disclosed as a high capacity cathode for rechargeable aqueous Zn-ion batteries, as well as methods for forming same to provide an improved cathode with significant improvements over existing cathode structures and materials.

An object of the present invention is to provide zirconium oxide nanoparticles that have excellent dispersibility in a polar solvent and are capable of increasing a core concentration in a dispersion liquid. Zirconium oxide nanoparticles according to the present invention are coated with at least one compound selected from the group consisting of R.sup.1—COOH, (R.sup.1O).sub.3-n—P(O)—(OH).sub.n, (R.sup.1).sub.3-n—P(O)—(OH).sub.n, (R.sup.1O)—S(O)(O)—(OH), R.sup.1—S(O)(O)—(OH), and (R.sup.1).sub.4-m—Si(R.sup.4).sub.m, wherein R.sup.1 represents a group comprising a carbon atom and at least one element selected from the group consisting of an oxygen atom, a nitrogen atom, and a sulfur atom, and having the total number of carbon atoms, oxygen atoms, nitrogen atoms, and sulfur atoms of 8 or less; R.sup.4 represents a halogen atom or —OR.sup.2, and R.sup.2 represents a hydrogen atom or an alkyl group; and n represents 1 or 2, and m represents an integer of 1 to 3.

A method embodiment involves preparing single metal or mixed transition metal chalcogenide using exfoliation of two or more different bulk transition metal dichalcogenides in a manner to form an intermediate hetero-layered transition metal chalcogenide structure, which can be treated to provide a single-phase transition metal chalcogenide.

A positive electrode active material for a non-aqueous electrolyte secondary battery achieves high output characteristics and battery capacity, and allows a high electrode density to be achieved in the case of using the material for a positive electrode of a battery; and a non-aqueous electrolyte secondary battery uses the positive electrode active material, thereby achieving a high output with a high capacity. Prepared is a nickel composite hydroxide including plate-shaped secondary particles aggregated with overlaps between plate surfaces of multiple plate-shaped primary particles, where shapes projected from directions perpendicular to the plate surfaces of the plate-shaped primary particles are any plane projection shape of spherical, elliptical, oblong, and massive shapes, and the secondary particles have an aspect ratio of 3 to 20, and a volume average particle size (Mv) of 4 μm to 20 μm measured by a laser diffraction scattering method.

A radical anion based functionalization of two-dimensional (2D) layered materials is proposed. The covalent functionalization of the basal plane of 2D materials with charge neutral radicals is typically unstable to reduction, leading to detachment of the functional groups from the basal plane upon reduction. This instability hinders the use of functionalized 2D materials as rechargeable electroactive species, unless the functional groups are bound to the edges of the 2D material. However, to achieve high capacity without the creation of many edges and defects, a stable functionalization of the basal plane in the reduced state is required. This goal can be achieved by radical anion functionalization, whereby the reduced/discharged state of the basal-plane-functionalized 2D material is produced. The product of the radical anion functionalization can be used as the discharged state of a cathode active material, solid electrolyte or part of a polymer composite.

A group of reductive 2D materials (R2D) with extended reactive vacancies and a method for making the R2D with extended reactive vacancies are provided, especially the example of the reductive boron nitride (RBN). To create defects such as vacancies, boron nitride (BN) powders are milled at cryogenic temperatures. Vacancies are produced by milling, and the vacancies can be used to reduce various metal nanostructures on RBN. Due to the thermal stability of the RBN and the enhanced catalytic performance of metal nanostructures, RBN-metals can be used for different catalysts, including electrochemical catalysts and high temperature catalysts.

A positive electrode active material for non-aqueous electrolyte secondary batteries that can achieve a high output characteristic and a high battery capacity when used in a positive electrode of a battery and that can achieve a high electrode density, and a non-aqueous electrolyte secondary battery that uses such a positive electrode active material and can achieve a high capacity and a high output. A lithium-manganese-cobalt composite oxide includes plate-shaped secondary particles each obtained by aggregation of a plurality of plate-shaped primary particles caused by overlapping of plate surfaces of the plate-shaped primary particles, wherein a shape of the primary particles is any one of a spherical, elliptical, oval, or a planar projected shape of a block-shaped object, and the secondary particles have an aspect ratio of 3 to 20 and a volume-average particle size (Mv) of 4 μm to 20 μm as measured by a laser diffraction scattering process.