JPH0359011B2 - - 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 YbFeZn ₇ O ₁₀ , which is a new compound useful as a magnetic material, a semiconductor material, a catalyst material, etc., and a method for producing the same. Conventional technology Conventionally, (Yb ³⁺ Fe ³⁺ O ₃ ) _o Fe ²⁺ O (n indicates an integer)
The compound having a hexagonal layered structure represented by is synthesized by the applicant and is known. YbFe ₂ O ₄ , Yb ₂ Fe ₃ O ₇ , Yb ₃ Fe ₄ O ₁₀ and
Lattice constant of Yb ₄ Fe ₅ O ₁₃ as hexagonal system, YbO _1.5
Table 1 shows the number of layers in the unit cell, FeO _1.5 layer, and Fe ₂ O _2.5 layer. These compounds have a layered structure in which YbFeO ₃ is thought to be combined at a ratio of n moles (n=1, 2, 3, . . . ) per mole of iron oxide (FeO).

[Table] Purpose of the invention The present invention is based on the chemical formula of (YbFeO ₃ ) _o FeO,
The object of the present invention is to provide a novel compound corresponding to n=1/7 and obtained by replacing Fe ²⁺ with Zn ₂₊ . Structure of the Invention The compound represented by YbFeZn ₇ O ₁₀ of the present invention is Yb ³⁺ (Fe ³⁺ ,Zn ²⁺ )Zn ₆ ²⁺ in the ionic crystal model.
Described as O ₁₀ ^2- , its structure is YbO _1.5 layers,
It is formed by laminating a (Fe,Zn)O _2.5 layer and a ZnO layer, and one of its characteristics is that it has significant structural anisotropy. 1/7 of Zn ²⁺ ion is
Together with Fe ³⁺ , (Fe ³⁺ , Zn ²⁺ )O _2.5 layers are formed, and the remaining 6/7 forms a ZnO layer. The lattice constants as a hexagonal crystal system are as follows. a = 3.307 ± 0.001 (Å) c = 72.19 ± 0.01 (Å) Planar index (hkl), interplanar 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 a magnetic material, a semiconductor material, and a catalytic material. For example, it is possible to use them as magnetic materials, semiconductors, and catalyst materials that have two-dimensional properties with strong anisotropy.

【table】

[Table] This compound can be produced by the following method. metal ytterbium or ytterbium oxide or a compound that decomposes into ytterbium oxide when heated; metal iron or iron oxide or a compound that decomposes into iron oxide when heated; metal zinc or zinc oxide or a compound that decomposes into zinc oxide when heated. Yb, Fe, and Zn are mixed in an atomic ratio of 1:1:7, and the mixture is heated at a temperature of 650°C or higher in the air, in an oxidizing atmosphere, or when Yb and Fe are Trivalent ion state,
It can be produced by heating in a reducing atmosphere in which Zn is not reduced from a divalent ion state. Commercially available starting materials 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 a magnetic 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 requires that the ratio of Yb, Fe, and Zn be in an atomic ratio of 1:1:7. 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
650℃ in a reducing atmosphere where Yb and Fe are not reduced from the trivalent ion state and Zn from the divalent ion state.
Heat above. 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 YbFeZn ₇ O ₁₀ compound powder was brown in color 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 _1.5 layers of YbO, _2.5 layers of (Fe, Zn)O, and a layer of ZnO. Example Ytterbium oxide (Yb ₂ O ₃ ) powder with a purity of 99.99% or more, iron oxide (Fe ₂ O ₃ ) powder with a purity of 99.9% or more, and reagent grade zinc oxide (ZnO) powder in a 1:1 molar ratio The mixture was weighed at a ratio of 14:1, 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, and then the sample was taken out of the furnace and rapidly cooled to room temperature. The obtained sample was a single phase of YbFeZn ₇ O ₁₀ , and the surface index (hkl),
The results of measuring the interplanar spacing (d _p ) and relative reflection intensity are shown in Table 2. The lattice constants as a hexagonal crystal system were a=3.307±0.001 (Å) and c=72.19±0.01 (Å). The above lattice constants and the surface index (hkl) in Table 2
The calculated interplanar spacing (d _c (Å)) is in extremely good agreement with the actually measured interplanar spacing (d _p (Å)). Effects of the Invention The present invention provides novel compounds useful as magnetic materials, semiconductor materials, and catalysts.

Claims (1)

[Claims] A compound having a hexagonal layered structure represented by 1 YbFeZn ₇ O ₁₀ . 2. Metallic ytterbium or yzterbium oxide or a compound that decomposes into ytterbium oxide when heated; Metallic iron or iron oxide or a compound that decomposes into iron oxide when heated; Metallic zinc or zinc oxide or a compound that decomposes into zinc oxide when heated. Yb, Fe, and Zn are mixed in an atomic ratio of 1:1:7, and the mixture is heated in the air, in an oxidizing atmosphere, or in an oxidizing atmosphere at a temperature of 650°C or higher. It is characterized by heating in a reducing atmosphere where Zn is less reduced than the trivalent ion state and the divalent ion state, respectively.
A method for producing a compound having a hexagonal layered structure represented by YbFeZn ₇ O ₁₀ .