A preparation method of a tetragonal NaV.sub.2O.sub.5.H.sub.2O nanosheet-like powder includes steps of: (S1) simultaneously adding NaVO.sub.3 and Na.sub.2S.9H.sub.2O into deionized water, and then magnetically stirring, and obtaining a black turbid solution; (S2) sealing after putting the black turbid solution into an inner lining of a reaction kettle, fixing the sealed inner lining in an outer lining of the reaction kettle, placing the reaction kettle into a homogeneous reactor, and then performing a hydrothermal reaction; and (S3) after completing the hydrothermal reaction, naturally cooling the reaction kettle to the room temperature, and then alternately cleaning through water and alcohol, and then collecting a product, drying the product, and finally obtaining the tetragonal NaV.sub.2O.sub.5.H.sub.2O nanosheet-like powder with a thickness in a range of 30-60 nm and a single crystal structure grown along a (002) crystal orientation.

Provided are a dielectric, a capacitor and a semiconductor device that include the dielectric, and a method of preparing the dielectric, the dielectric including: a composition represented by Formula 1; and an oxide including a perovskite type crystal structure having a polar space group or a non-polar space group other than a Pbnm space group:
A.sub.xB.sub.yO.sub.3-<Formula 1> wherein, in Formula 1, A is a monovalent, divalent, or trivalent cation, B is a trivalent, tetravalent, or pentavalent cation, and 0.5x1.5, 0.5y1.5, and 00.5.

A down-converted light emitting combination that generates a visible light when an ultraviolet light is incident is provided. The down-converted light emitting combination includes a first structure made of a first material that generates a visible light of a first color when an ultraviolet light of a first wavelength range is incident and a second structure made of a second material that generates a visible light of a second color different from the first color when the ultraviolet light of a second wavelength range different from the first wavelength range is incident, and the first material and the second material have different emission colors and distributions of intensities of the visible lights generated depending on a wavelength of the incident ultraviolet light.

The present invention discloses a method for preparing a vanadium battery electrolyte by using a waste vanadium catalyst. The method includes step A: soaking a waste vanadium catalyst in an oxalic acid solution for 2-8 h, to generate a solution containing vanadyl oxalate; step B: cleaning the waste vanadium catalyst, and collecting the vanadyl oxalate solution; and step C: adding a polyacid ester into the vanadyl oxalate solution; and after full reaction, removing impurities by filtration, and concentrating the filtrate to obtain a vanadyl oxalate mother solution. The method for preparing a vanadium battery electrolyte by using a waste vanadium catalyst according to the present invention does not generate wastes which cause environmental pollution in the treatment process, and can make a solution in the waste vanadium catalyst treatment process generate the electrolyte for preparing a vanadium battery. The process is simple and the treatment cost is low.

The present invention discloses a method for preparing a vanadium battery electrolyte by using a waste vanadium catalyst. The method includes step A: soaking a waste vanadium catalyst in an oxalic acid solution for 2-8 h, to generate a solution containing vanadyl oxalate; step B: cleaning the waste vanadium catalyst, and collecting the vanadyl oxalate solution; and step C: adding a polyacid ester into the vanadyl oxalate solution; and after full reaction, removing impurities by filtration, and concentrating the filtrate to obtain a vanadyl oxalate mother solution. The method for preparing a vanadium battery electrolyte by using a waste vanadium catalyst according to the present invention does not generate wastes which cause environmental pollution in the treatment process, and can make a solution in the waste vanadium catalyst treatment process generate the electrolyte for preparing a vanadium battery. The process is simple and the treatment cost is low.

In general, the present disclosure is directed to methods for synthesizing vanadium oxide nanobelts, as well as the corresponding chemical composition of the vanadium oxide nanobelts. Also described are materials which can incorporate the vanadium oxide nanobelts, such as including the vanadium oxide nanobelts as a cathode material for use in energy storage applications (e.g., batteries). The vanadium oxide nanobelts described herein display structural characteristics that may provide improved diffusion and/or charge transfer between ions. Thus, batteries incorporating implementations of the current disclosure may demonstrate improved properties such as higher capacity retention over charge discharge cycling.

A foreign element-containing vanadium sulfide contains, as constituent elements, vanadium, sulfur, and a foreign element, wherein the compositional ratio of the foreign element to the vanadium (M1/V) is in the range of 0.05 to 1.5 in terms of molar ratio; the compositional ratio of the sulfur to the vanadium (S/V) is in the range of 3.0 to 10.0 in terms of molar ratio; and the foreign element includes at least one member selected from the group consisting of Nb, Ti, Zr, Mo, Sc, and Y, or includes at least one member selected from the group consisting of Li, B, N, O, F, Mg, S, Cl, Ca, Br, Sr, Sc, I, Fe, Co, Ni, Zn, Y, Mo, Tc, and Cd. The foreign element-containing vanadium sulfide is an electrode active material for a lithium ion secondary battery that exhibits satisfactorily high initial capacity and that provides improved electrochemical performance or cycle performance.

A foreign element-containing vanadium sulfide contains, as constituent elements, vanadium, sulfur, and a foreign element, wherein the compositional ratio of the foreign element to the vanadium (M1/V) is in the range of 0.05 to 1.5 in terms of molar ratio; the compositional ratio of the sulfur to the vanadium (S/V) is in the range of 3.0 to 10.0 in terms of molar ratio; and the foreign element includes at least one member selected from the group consisting of Nb, Ti, Zr, Mo, Sc, and Y, or includes at least one member selected from the group consisting of Li, B, N, O, F, Mg, S, Cl, Ca, Br, Sr, Sc, I, Fe, Co, Ni, Zn, Y, Mo, Tc, and Cd. The foreign element-containing vanadium sulfide is an electrode active material for a lithium ion secondary battery that exhibits satisfactorily high initial capacity and that provides improved electrochemical performance or cycle performance.

Provided are the following: a mixture of visible light-responsive photocatalytic titanium oxide fine particles which can conveniently produce a photocatalyst thin film that exhibits photocatalyst activity even with only visible light (400-800 nm) and that exhibits high transparency; a dispersion liquid of the fine particles; a method for producing the dispersion liquid; a photocatalyst thin film; and a member having the photocatalyst thin film on a surface thereof. The mixture of visible light-responsive photocatalytic titanium oxide fine particles is characterized by containing two kinds of titanium dioxide fine particles: first titanium oxide fine particles, in which a tin component and a transition metal component (excluding an iron group element component) that increases visible light response properties form a solid solution, and second titanium oxide fine particles, in which an iron group element component and a chromium group element component form a solid solution.

Provided are the following: a mixture of visible light-responsive photocatalytic titanium oxide fine particles which can conveniently produce a photocatalyst thin film that exhibits photocatalyst activity even with only visible light (400-800 nm) and that exhibits high transparency; a dispersion liquid of the fine particles; a method for producing the dispersion liquid; a photocatalyst thin film; and a member having the photocatalyst thin film on a surface thereof. The mixture of visible light-responsive photocatalytic titanium oxide fine particles is characterized by containing two kinds of titanium dioxide fine particles: first titanium oxide fine particles, in which a tin component and a transition metal component (excluding an iron group element component) that increases visible light response properties form a solid solution, and second titanium oxide fine particles, in which an iron group element component and a chromium group element component form a solid solution.