JPH0338211B2 - - 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 YbFeZnMgO ₅ , which is a new compound useful as a magnetic material, a semiconductor material, and a catalytic 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, 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] Purpose of the invention The present invention is based on the chemical formula of (YbFeO ₃ ) _o FeO,
Corresponds to n = 1/2, and instead of Fe ²⁺ (Zn ²⁺ +
An object of the present invention is to provide a novel compound obtained by replacing Mg ²⁺ ). Constitution of the Invention The compound represented by YbFeZnMgO ₅ of the present invention is
In the ionic crystal model, Yb ³⁺ (Fe ²⁺ , Zn ²⁺ )
Described as Mg ²⁺ O ₅ ^2- , its structure is YbO _1.5
It is formed by laminating layers, (Fe ³⁺ , Zn ²⁺ )O _2.5 layers, and MgO layers, and one of its characteristics is that it has significant structural anisotropy. Zn ²⁺ is
Creates (Fe ³⁺ , Zn ²⁺ )O _2.5 layer with Fe 3+ ^and Mg ²⁺
creates an MgO layer. The lattice constants as a hexagonal crystal system are as follows. a=3.400±0.001 (Å) c=21.82±0.01 (Å) Planar index (hKl), plane spacing (d (Å)) of this compound
(d _p is the measured value, d _c is the counted 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 it as a magnetic material, a semiconductor, and a catalytic material that has 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, Zn
and Mg in an atomic ratio of 1:1:1:1, and the mixture is heated at a temperature of 600°C or higher in the air, in an oxidizing atmosphere, or when Yb and Fe are in a trivalent state, Zn and Mg are each in a trivalent state. is obtained by heating in a reducing atmosphere in which the compound is not reduced from the divalent 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 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. Thoroughly mix the raw materials as they are or with alcohols, acetone, etc. The mixing ratio of the raw materials needs to be 1:1:1:1 in atomic ratio of Yb, Fe, Zn, and Mg. This naturally makes it impossible to obtain a single phase of the desired compound. This mixture is stored in the air, in an oxidizing atmosphere, or
In a reducing atmosphere where Yb and Fe are not reduced from their trivalent states, and Zn and Mg are not reduced from their divalent states.
Heat over 600℃. 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 YbFeZnMgO ₅ compound powder was brown in color and was found to have a crystalline structure by powder X-ray diffraction. The crystal structure was found to be layered, consisting of _1.5 layers of YbO, _2.5 layers of (Fe, Zn)O, and a stack of MgO layers. Examples 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, reagent grade zinc oxide (ZnO), and reagent grade magnesium oxide (MgO) The powder was weighed in a molar ratio of 1:1:2:2, ethanol was added in an agate mortar, and the mixture was 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 1300°C, and heated for 3 days, after which the sample was taken out of the furnace and rapidly quenched to room temperature. The obtained sample is YbFeZnMgO ₅ single phase,
By powder X-ray diffraction method, the interplanar spacing of each reflection (d _p )
The results of measuring the relative reflection intensity are shown in Table 2. The lattice constants as a hexagonal crystal system were as follows. a=3.400±0.001 (Å) c=21.82±0.01 (Å) The above lattice constant and each plane index (h
The interplanar spacing (d _c (Å)) calculated from Kl) was 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] 1. A compound having a hexagonal layered structure represented by YbFeZnMgO ₅ . 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,
Zn and Mg are mixed in an atomic ratio of 1:1:1:1, and the mixture is heated at a temperature of 600°C or higher in the air, in an oxidizing atmosphere, or when Yb and Fe are in the trivalent state, Zn and A method for producing a compound having a hexagonal layered structure represented by YbFeZnMgO ₅ , which comprises heating in a reducing atmosphere in which Mg is not reduced beyond a divalent state.