JPH0435405B2 - - 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 ScFeZn ₃ O ₆ , 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 Yb ₄
Lattice constant of Fe ₅ O ₁₃ as hexagonal system, YbO _1.5 layer,
Table 1 shows the number of layers in the unit cell of _1.5 FeO layers and _2.5 Fe ₂ O layers. 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,
Corresponds to n = 1/3, Sc ³⁺ instead of Yb ³⁺ , Fe ²⁺
The object of the present invention is to provide a novel compound obtained by replacing Zn ²⁺ in place of Zn 2+ . Structure of the Invention In the ionic crystal model, the compound represented by ScFeZn ₃ O ₆ of the present invention is Sc ³⁺ (Fe ³⁺ , Zn ²⁺ )Zn ₂ ²⁺ O ₆ ^2
- , its structure is ScO _1.5 layer, (Fe,
It is formed by laminating Zn)O _2.5 layers and ZnO layers, and one of its characteristics is that it has significant structural anisotropy. One-third of the Zn ²⁺ ions together with Fe ³⁺ form the (Fe ³⁺ , Zn ²⁺ )O _2.5 layer, and the remaining two-thirds form the ZnO layer. The lattice constants as a hexagonal crystal system are as follows. a=3.274±0.001 (Å) c=41.59±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. Scandium metal or scandium oxide or a compound that decomposes into scandium oxide when heated; Metallic iron or iron oxide or a compound that decomposes into iron oxide when heated; Zinc metal or zinc oxide or a compound that decomposes into zinc oxide when heated. are mixed in an atomic ratio of Sc, Fe, and Zn in an atomic ratio of 1:1:3, and the mixture is
It can be produced by heating at a temperature of 600° C. or higher in the air, an oxidizing atmosphere, or a reducing atmosphere in which Sc and Fe are not reduced to a trivalent ion state and Zn is not reduced to 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 atomic ratio of Sc, Fe, and Zn be 1:1:3. 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
At 600℃ in a reducing atmosphere where Sc 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 powder of the ScFeZn ₃ O ₆ compound 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 ScO, _2.5 layers of (Fe, Zn)O, and a layer of ZnO. Example Scandium oxide (Sc ₂ O ₃ ) with a purity of 99.99% or more
Powder, iron oxide (Fe ₂ O ₃ ) powder with a purity of 99.9% or more,
Weighed reagent-grade zinc oxide (ZnO) powder at a molar ratio of 1:1:6, added ethanol in an agate mortar, and mixed for about 30 minutes to form a fine powder mixture with an average particle size of several μm. Obtained. The mixture was sealed in a platinum tube, placed in a tubular siliconite furnace set at 1450°C, and heated for 5 days, and then the sample was taken out of the furnace and rapidly cooled to room temperature. The obtained sample is _a single phase of _ScFeZn3O6 ,
The results of measuring each plane index (hkl), plane spacing (d _p ), and relative reflection intensity by powder X-ray diffraction method are shown in Table-
2 was true. The lattice constants as a hexagonal crystal system were a=3.274±0.001 (Å) and c=41.59±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] 1. A compound having a hexagonal layered structure represented by ScFeZn ₃ O ₆ . 2 Scandium metal or scandium oxide or a compound that decomposes into scandium 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 Sc, Fe, and Zn in an atomic ratio of 1:1:3, and the mixture is
ScFeZn ₃ O 6 is heated at a temperature of 600°C or higher in the air, in an oxidizing atmosphere, or in a reducing atmosphere in which Sc and Fe are not reduced to a trivalent ion state and Zn is not reduced to a divalent ion _state . A method for producing a compound having a hexagonal layered structure as shown.