JPH0359009B2 - - 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 InFeZnMgO ₅ , which is a new compound useful as a magnetic material, a semiconductor material, and a catalyst material, 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 n moles of YbFeO ₃ are combined with 1 mole of iron oxide (FeO).

【table】

[Table] Purpose of the invention The present invention is based on the chemical formula of (YbFeO ₃ ) _o FeO, where n = 1/2, and In ₃₊ instead of Yb ³⁺ ,
The object of the present invention is to provide a novel compound obtained by replacing Fe ²⁺ with (Zn ²⁺ +Mg ²⁺ ). Structure of the Invention The compound represented by InFeZnMgO ₅ of the present invention is described as In ³⁺ (Fe ³⁺ Zn ²⁺ )Mg ²⁺ O ₅ ^2- in the ionic crystal model, and its structure consists of _1.5 layers of InO, (Fe, Zn) _O2.5
It is formed by laminating layers and MgO layers,
One of its characteristics is that it has significant structural anisotropy. Zn ²⁺ forms the (Fe ³⁺ , Zn ²⁺ )O _2.5 layer together with Fe 3+, ^and Mg ²⁺ forms the MgO layer. The lattice constants as a hexagonal crystal system are as follows. a=3.324±0.001 (Å) c=22.32±0.01 (Å) Planar index (hkl), plane spacing (d ₀ (Å)) of this compound
(d ₀ is the measured value, d _c is the 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, a catalytic material, and the like.

【table】

【table】

[Table] This compound can be produced by the following method. Metallic indium or indium oxide or a compound that decomposes into indium 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. , metallic magnesium, magnesium oxide, or a compound that decomposes into magnesium oxide by heating, and In, Fe, Zn, and Mg in an atomic ratio of 1:1:1:1, and the mixture is
In air, oxidizing atmosphere or In
and Fe are each in the trivalent state, and Mg and Zn are each in the 2-valent state.
It can be produced by heating in a reducing atmosphere that does not reduce the valence state. Commercially available starting materials used in the present invention can be used as they are, but in order to allow the chemical reaction to proceed rapidly, the smaller the particle size, the better, particularly preferably 10 μm or less. Further, when used as a magnetic material or a semiconductor material, it is preferable to use a material with high purity to avoid contamination with impurities. These are thoroughly mixed as is or with alcohol, acetone, etc. These mixing ratios are 1:1:1:1 in atomic ratio of In, Fe, Mg, and Zn.
If this ratio is exceeded, a single phase of the target compound cannot be obtained. This mixture is stored in the air, in an oxidizing atmosphere, or in a state where In and Fe are each in a trivalent state.
Heating is performed at 600° C. or higher in a reducing atmosphere in which Mg and Zn are not reduced from their divalent state. Heating time is several hours or more. There are no restrictions on the rate of temperature increase during heating. After heating, cool it down quickly or
Alternatively, it can be rapidly drawn out into the atmosphere. The obtained InFeZnMgO ₅ 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 is formed by stacking _1.5 layers of InO, _2.5 layers of (Fe ³⁺ Zn ²⁺ )O, and MgO layers. Example: Indium oxide powder with a purity of 99.99% or higher, purity
Weigh out 99.9% or more iron oxide powder, reagent grade magnesium oxide powder, and reagent grade zinc oxide powder in a molar ratio of 1:1:2:2, add ethanol in a mortar, and mix for about 30 minutes. A fine powder mixture with an average particle size of several μm was obtained. The mixture was sealed in a platinum tube, placed in a tubular siliconite furnace set at 1300°C, and heated for 3 days, after which the sample was taken out of the furnace and rapidly cooled to room temperature. The obtained sample is InFeZnMgO ₅ single phase,
By powder X-ray diffraction method, the interplanar spacing of each reflection (d _p )
and the relative reflection intensity was measured. The results are shown in the table-
2 was true. The lattice constants as a hexagonal crystal system were as follows. a=3.324±0.001 (Å) c=22.32±0.01 (Å) The interplanar spacing [d _c (Å)] calculated from this lattice constant and each reflection (hkl) in Table 2 is the actually measured interplanar spacing [d _c (Å)] was in good agreement. Effects of the Invention The present invention provides novel compounds useful as magnetic materials, semiconductor materials, and catalysts.

Claims (1)

[Claims] 1. A compound having a hexagonal layered structure represented by InFeZnMgO ₅ . 2 Metallic indium or indium oxide or a compound that decomposes into indium 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. and metallic magnesium, magnesium oxide, or a compound that decomposes into magnesium oxide upon heating, in an atomic ratio of In, Fe, Zn, and Mg of 1:1:1:1, and the mixture is heated at 600°C or higher. in air, oxidizing atmosphere or
In and Fe are each in trivalent state, Mg and Zn are each in 2 state
1. A method for producing a compound having a hexagonal layered structure represented by InFeZnMgO ₅ , which comprises heating in a reducing atmosphere that does not reduce the valence state.