A method for producing a fluoride fluorescent material comprises: preparing fluoride particles having a composition containing at least one element or ion A selected from the group consisting of alkaline metal elements and NH.sub.4.sup.+, at least one element M selected from the group consisting of Group-4 elements and Group-14 elements, Mn.sup.4+, and F, in which a molar ratio of A in 1 mol of the composition is 2, a total molar ratio of M and Mn.sup.4+ is 1, a molar ratio of Mn.sup.4+ is in a range of more than 0 and less than 0.2, and a molar ratio of F is 6; subjecting the fluoride particles to a first heat treatment at a temperature of 500 C. or more in an inert gas atmosphere; washing the first heat-treated fluoride particles with a washing liquid; and bringing the washed fluoride particles into contact with a fluorine-containing substance and subjecting the resulting fluoride particles to a second heat treatment at a temperature of 400 C. or more.

A coalizing product and a method for the coalescing of oil contaminants from a water flow is described, in which the product according to the invention is arranged in an apparatus for in depth coalescing of oil contaminated water. There are also disclosed uses of the method and the product for coalescing of oil contamination in water.

A coalizing product and a method for the coalescing of oil contaminants from a water flow is described, in which the product according to the invention is arranged in an apparatus for in depth coalescing of oil contaminated water. There are also disclosed uses of the method and the product for coalescing of oil contamination in water.

The present disclosure discloses a method for growing a crystal in oxygen atmosphere. The method may include compensating a weight of a reactant, introducing a flowing gas, improving a volume ratio of oxygen during a cooling process, providing a heater in a temperature field, and optimizing parameters. According to the method, problems may be solved, for example, cracking and component deviation of the crystal during a crystal growth process, and without oxygen-free vacancy. The method for growing the crystal may have excellent repeatability and crystal performance consistency.

An embodiment of the present invention relates to a porous silicon composite, a porous silicon-carbon composite comprising same, and an anode active material, wherein the porous silicon composite and the porous silicon-carbon composite each comprise silicon particles and a magnesium compound together and satisfy a molar ratio (O/Si) of oxygen (O) atom to silicon (Si) atom in a specific range, so that the application of the porous silicon composite and the porous silicon-carbon composite to an anode active material leads to an excellent capacity retention rate as well as a significant improvement in discharge capacity and initial efficiency.

A red phosphor that has optical characteristics and durability under high-temperature and high-humidity environments, and a method for producing the same. The red phosphor includes a Mn-activated complex fluoride represented by the following general formula (1) and bismuth:
A2MF6:Mn4+(1)
wherein A represents at least one alkali metal element selected from the group consisting of lithium, sodium, potassium, rubidium and cesium, and M represents at least one tetravalent element selected from the group consisting of silicon, germanium, tin, titanium, zirconium and hafnium.

The present invention relates to a method for producing a hexafluoromanganate(IV), said method being characterized by comprising: inserting an anode and a cathode into a reaction solution that contains a compound containing manganese having an atomic valence of less than 4 and/or manganese having an atomic valence of more than 4 and hydrogen fluoride; and then applying an electric current having an electric current density of 100 to 1000 A/m.sup.2 between the anode and the cathode. According to the present invention, it becomes possible to produce a hexafluoromanganate(IV) in which the content ratio of manganese having an atomic valence of 4 is high and the contamination with oxygen is reduced and which has high purity. When a complex fluoride red phosphor is produced using the hexafluoromanganate(IV) as a raw material, the phosphor produced has high luminescence properties, particularly high internal quantum efficiency.

The present invention relates to a method for producing a hexafluoromanganate(IV), said method being characterized by comprising: inserting an anode and a cathode into a reaction solution that contains a compound containing manganese having an atomic valence of less than 4 and/or manganese having an atomic valence of more than 4 and hydrogen fluoride; and then applying an electric current having an electric current density of 100 to 1000 A/m.sup.2 between the anode and the cathode. According to the present invention, it becomes possible to produce a hexafluoromanganate(IV) in which the content ratio of manganese having an atomic valence of 4 is high and the contamination with oxygen is reduced and which has high purity. When a complex fluoride red phosphor is produced using the hexafluoromanganate(IV) as a raw material, the phosphor produced has high luminescence properties, particularly high internal quantum efficiency.

The present disclosure relates to the technical field of photocatalysis/electrocatalysis, and in particular to a non-metallic high-entropy compound, and a preparation method and use thereof. In the present disclosure, the non-metallic high-entropy compound includes at least five non-metallic elements, where each of the at least five non-metallic elements has a molar proportion of 0.1% to 99.0%, and a total atomic proportion of the at least five non-metallic elements are 100%. The non-metallic high-entropy compound has a controllable band gap, an adjustable conductivity, and a desirable surface activity, and shows a catalytic reaction activity for hydrogen production by high-efficiency photocatalytic/electrocatalytic water splitting, carbon dioxide reduction, or organic pollutant degradation. Moreover, synthetic raw materials are all non-metals, which are cheap and easily available, while a synthesis process is simple and easy to implement.

The present disclosure relates to the technical field of photocatalysis/electrocatalysis, and in particular to a non-metallic high-entropy compound, and a preparation method and use thereof. In the present disclosure, the non-metallic high-entropy compound includes at least five non-metallic elements, where each of the at least five non-metallic elements has a molar proportion of 0.1% to 99.0%, and a total atomic proportion of the at least five non-metallic elements are 100%. The non-metallic high-entropy compound has a controllable band gap, an adjustable conductivity, and a desirable surface activity, and shows a catalytic reaction activity for hydrogen production by high-efficiency photocatalytic/electrocatalytic water splitting, carbon dioxide reduction, or organic pollutant degradation. Moreover, synthetic raw materials are all non-metals, which are cheap and easily available, while a synthesis process is simple and easy to implement.