JPH0333650B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a compound having a hexagonal layered structure represented by YbGaZn ₆ θ ₉ , which is a new compound useful as an optical functional material, a semiconductor material, and a catalyst material, and a method for producing the same. Conventional technology Conventionally, (Yb ³⁺ Fe ³⁺ θ ₃ ) _o Fe ²⁺ θ (n indicates an integer)
The compound having a hexagonal layered structure represented by is synthesized by the applicant and is known. YbFe ₂ θ ₄ , Yb ₂ Fe ₃ θ ₇ , Yb ₃ Fe ₄ θ ₁₀ and
Lattice constant as hexagonal system of Yb ₄ Fe ₅ θ ₁₃ , Ybθ _1.5 layer,
Table 1 shows the number of Feθ _1.5 layers and Fe ₂ θ _2.5 layers in the unit cell. These compounds have a layered structure in which n moles of YbFeθ ₃ are combined with 1 mole of iron oxide (Feθ).

[Table] Purpose of the Invention The present invention is based on the chemical formula of (YbFeθ ₃ ) _o Feθ, where n
= 1/6 and is obtained by replacing Ga ³⁺ in place of Fe ^{3+ and} Zn ²⁺ in place of Fe 2+. Structure of the Invention In the ionic crystal model, the compound represented by YbGaZn ₆ θ ₉ of the present invention is Yb ³⁺ (Ga ³⁺ Zn ²⁺ )
It is described as Zn ₅ ²⁺ θ ₉ ^2- , and its structure consists of Ybθ _1.5 layers,
It is formed by laminating a (Ga ³⁺ Zn ²⁺ ) θ _2.5 layer and a Znθ layer, and one of its characteristics is that it has significant structural anisotropy. 1/6 of Zn ²⁺ forms a (Ga ³⁺ , Zn ^{2+ )} θ _2.5 layer with Ga 3+, and the remaining 5/6
Creates a Znθ layer. The lattice constants as a hexagonal crystal system are as follows. a = 3.305 ± 0.001 (Å) c = 42.08 ± 0.01 (Å) Planar index (hkl), plane spacing (d (Å)) of this compound
(d _p is an actual measured value, d _c is a calculated value) and the relative reflection intensity (I (%)) for X-rays is shown in Table 2. This compound is useful as an optical functional material, a semiconductor material, and a catalyst material.

【table】

[Table] This compound can be produced by the following method. Metallic ytterbium or ytterbium oxide or a compound that decomposes into ytterbium oxide by heating; Metallic gallium or gallium oxide or a compound that decomposes into gallium oxide by heating; Metallic zinc or zinc oxide or a compound that decomposes into zinc oxide by heating. Yb,
Ga and Zn are mixed in an atomic ratio of 1:1:6, and the mixture is heated at a temperature of 650°C or higher in the air, in an oxidizing atmosphere, or in an oxidizing atmosphere where Yb and Ga are each in a trivalent ion state and Zn is in a trivalent ion state. It can be produced by heating in a reducing atmosphere that does not reduce the divalent ion state. Commercially available starting materials used in the present invention may be used as they are, but in order for the chemical reaction to proceed quickly, it is better to have a small particle size, especially 10 μm.
It is preferable that it is below. Further, when used as an optical functional material or a semiconductor material, it is preferable to have high purity since contamination with impurities is avoided. Examples of compounds whose starting materials yield metal oxides by heating include hydroxides, carbonates, and nitrates of the respective metals. The raw materials are thoroughly mixed as they are or together with alcohols, acetone, etc. The mixing ratio of the raw materials needs to be such that the ratio of Yb, Ga, and Zn is in an atomic ratio of 1:1:6. If this is removed, a single phase of the target compound cannot be obtained. This mixture is stored in the air, in an oxidizing atmosphere, or
Yb and Ga are each in a trivalent ion state, Zn is each in a divalent state
In a reducing atmosphere that does not reduce from the valent ion state
Heat at 650℃ or higher. Heating time is several hours or more. There are no restrictions on the rate of temperature increase during heating. After heating, it can be rapidly cooled, or it can be rapidly drawn out into the atmosphere. The obtained YbGaZn ₆ θ ₉ compound powder was colorless and was found to have a crystalline structure by powder X-ray diffraction. Its crystal structure is layered,
It was found that it was formed by stacking a Ybθ _1.5 layer, a (Ga, Zn)θ _2.5 layer, and a Znθ layer. Example: Ytterbium oxide (Yb ₂ θ ₃ ) powder with a purity of 99.99% or more, gallium oxide (Ga ₂ θ ₃ ) powder with a purity of 99.9% or more, and reagent grade zinc oxide (Znθ) powder in a 1:1 molar ratio. The mixture was weighed at a ratio of 12 to 12, ethanol was added in an agate mortar, and mixed for about 30 minutes to obtain a fine powder mixture with an average particle size of several μm. The mixture was sealed in a platinum tube, placed in a tubular siliconite furnace set at 1450°C, and heated for 4 days, after which the sample was taken out of the furnace and rapidly cooled to room temperature. The obtained sample is YbGaZn ₆ θ ₉ single phase,
The results of measuring the plane index (hkl), plane spacing (d _p ), and relative reflection intensity by powder X-ray diffraction are shown in Table-
2 was true. The lattice constants as a hexagonal crystal system were a=3.305±0.001 (Å) and c=42.80±0.01 (Å). The above lattice constants and the surface index (hkl) in Table 2
The calculated interplanar spacing (d _c (Å)) was in excellent agreement with the actually measured interplanar spacing (do (Å)). Effects of the Invention The present invention provides novel compounds useful as optical functional materials, semiconductor materials, and catalysts.

Claims (1)

[Claims] A compound having a hexagonal layered structure represented by 1 YbGaZn ₆ θ ₉ . 2 Metallic ytterbium or ytterbium oxide or a compound that decomposes into ytterbium oxide when heated; Metallic gallium or gallium oxide or a compound that decomposes into gallium oxide when heated; Metallic zinc or zinc oxide or a compound that decomposes into zinc oxide when heated. A compound that is
Yb, Ga, and Zn are mixed in an atomic ratio of 1:1:6, and the mixture is heated to a temperature of 650°C or higher in the air, in an oxidizing atmosphere, or when Yb and Ga are each in a trivalent ion state, Zn 1. A method for producing a compound having a hexagonal layered structure represented by YbGaZn 6 θ 9 , which comprises heating in a reducing atmosphere in which YbGaZn ₆ θ ₉ is not reduced to a divalent ion state.