JPS5933541B2 - Compound with hexagonal layered structure represented by HoGaMnO↓4 and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel compound HoGaMn04 having a hexagonal layered structure and a method for producing the same.

Conventionally, YFe.

A compound having a hexagonal layered structure represented by 04 is known.

This compound is a compound in which divalent and trivalent iron ions are surrounded by five-coordinated oxygen ions, and Y has six-coordinated oxygen ions around it, as shown by Y3+Fe2+Fe3+OH-. It has magnetism. The present invention is a compound of Y3+Fe2+Fe3+OH-. Things Y3+
Ho3+ instead of , Mn2+ instead of Fe″f (Fe
The object of the present invention is to provide a novel compound in which Ga3- is substituted for 3+, and a method for producing the same. HoGaMn of the present invention
In the compound shown by 04, holmium exists as Ho3+ ion, manganese exists as Mn2+, and gallium exists as trivalent ion, and Ho3+Ga3+Mn2+
It can be expressed as a river. This crystal has a hexagonal layered structure as shown in FIG. The largest circle indicates oxygen, the middle circle indicates holmium, and the smallest black circle indicates gallium and manganese. Ga and Mn are entered randomly. The divalent ions of manganese and the trivalent ions of gallium are surrounded by five-coordinated oxygen ions and occupy the same position crystallographically. Moreover, Ho has six-coordinated oxygen around it. Oxygen, an anion, has a dense structure. The plane index (hkl) of this crystal, the plane spacing (d included) (do is the actual measurement, dc is the calculated value), the relative reflection intensity for X-rays (
I%) are shown in Table 1.

The space group is R'm, its crystal habit is plate-like, and its lattice constant is as follows: ao ■ 34905±O, 000
4(λ)Co■ 25.136±O, 008 (in) 1st
Table HoGaMnO4 This compound is useful as a catalytic material as well as a semiconductor material.

This compound can be produced by the following method.

Holmium oxide (HO2O3), manganese oxide (M
nO) and gallium oxide (Ga2O3) in a molar ratio of about 1:2:1, and heating the mixture at a temperature of 1000 ° C. or higher in a non-oxidizing atmosphere. can. The holmium oxide used in the present invention may be used as it is, but in order to speed up the reaction between the oxides, the smaller the particle size, the better, particularly preferably 10 μm or less.

Furthermore, when used as a semiconductor material, contamination with impurities is avoided, so it is desirable that the raw material be of high purity and that it be calcined in air at about 1000° C. for several hours. Manganese oxide of ordinary reagent grade level may be used.

The particle size is 10 μm for the same reason as the holmium oxide mentioned above.
It is preferable that it is below. Further, it is preferable to calcinate in a mixed gas of carbon dioxide and hydrogen (mixing ratio: 1:1 by volume) at 1000'C for one day, and then rapidly cool to 0°C, as this will speed up the reaction. The gallium oxide may be of special reagent grade.
As mentioned above, the particle size is preferably 10 μm or less. Moreover, it is preferable to calcined in air at 800° C. for one day. These raw materials are thoroughly mixed as they are or with alcohol, acetone, etc. added. These mixing ratios are HO2O3, MnO. The molar ratio of Ga2O3 is 1:2:1. If this ratio is exceeded, the desired layered compound cannot be obtained. These mixtures are sealed in a quartz or platinum container and heated under a non-oxidizing atmosphere.

Since manganese is in a divalent state, in an oxidizing atmosphere (for example, in the atmosphere), manganese will be oxidized and become trivalent, so it is necessary to be in a non-oxidizing atmosphere. The heating temperature may be 1000° C. or higher, and the heating time may be 10 minutes or more, preferably 1 hour or more. There are no restrictions on the rate of temperature increase during heating. After the reaction is completed, it may be rapidly cooled to O'C or rapidly drawn out into the atmosphere. The obtained HOGaMnO4 compound had a black metallic luster and was found to have a crystalline structure by powder X-ray diffraction.

The weight of the sample was precisely weighed before and after heating, and the stoichiometric number of the obtained compound was determined. Example Holmium oxide (HO2O3) powder with a purity of 99.9% or more, manganese oxide (MnO) powder with a purity of 99.9% or more, and gallium oxide (Ga2O3) powder with a purity of 99.9% or more in a molar ratio of 1 The mixture was weighed at a ratio of 2:1, and acetone was added in a mortar and mixed thoroughly to obtain a fine powder mixture with an average particle size of several μm.

The mixture was placed in a platinum tube (inner diameter 8 m7fL) and sealed. This was placed in a box-shaped siliconite furnace set at 1300°C and heated for about 3 days, after which the sample was taken out.
Cool rapidly to room temperature. What was obtained was HOGaMn
It was a hexagonal layered compound of O4. The properties of the crystal were as shown in Table 1.

[Brief explanation of the drawing]

The drawing is a diagram of the HOGaMnO4 crystal of the present invention. The largest circle indicates oxygen, the middle circle indicates holmium, and the smallest black circle indicates gallium and manganese.

Claims (1)

[Claims] 1. A compound having a hexagonal layered structure represented by HoGaMnO_4. 2 Holmium oxide (Ho_2O_3), manganese oxide (MnO) and gallium oxide (Ga_2O_3)
are mixed in a molar ratio of approximately 1:2:1, and this mixture is heated at a temperature of 1000°C or higher in a non-oxidizing atmosphere to form a hexagonal layered structure represented by HoGaMnO_4. A method for producing a compound having