JPS5933540B2 - Compound having hexagonal layered structure represented by ErGaMnO↓4 and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel compound ErGaMnO4 having a hexagonal layered structure and a method for producing the same.

Conventionally, compounds having a hexagonal layered structure represented by YFe2O4 are known.

In this compound, as shown by Y3+Fe2+Fe3+Kawaichi, divalent and trivalent iron ions are surrounded by five-coordinated oxygen ions, and Y has six-coordinated oxygen ions around it. , has magnetic properties. The present invention provides a novel compound in which Er3+ is substituted for Y3+, Mn2+ is substituted for Fe2+, and Ga3+ is substituted for Fe3+ in the compound Y3+Fe゛+Fe゜+OH-, and a method for producing the same. In the compound represented by ErGaMn04 of the present invention, erbium is Er3
+ ions, manganese exists as Mn2+, and gallium exists as trivalent ions, Er3+Ga3+Mn2+OH-
It can be expressed as This crystal has a hexagonal layered structure as shown in FIG. The largest circle indicates oxygen, the middle circle indicates erbium, and the smallest black circle indicates gallium and manganese. Ga and Mn are entered randomly. Manganese 2
The valence ions and the trivalent ions of Ga are surrounded by five-coordinated oxygen ions and occupy the same position crystallographically. Furthermore, Er has six-coordinated oxygen atoms around it. Oxygen, an anion, has a dense structure. Table 1 shows the plane index (hkl), plane spacing (d) (do indicates actual measurement, dc indicates calculated value), and relative X-ray reflection intensity (I%) of this crystal.

The space group is R'm, its crystal habit is plate-like, and its lattice constant is as follows: a0 = 13.4737±O, 00
02 (λ) c0 = 25.298 ± O, oo5 (λ) 1st
Table ErGaMn04 This compound is useful as a catalytic material as well as a semiconductor material.

This compound can be produced by the following method.

Erbium oxide (Er2O3), 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. Commercially available erbium oxides used in the present invention may be used as they are, 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 erbium 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 (mixture ratio: 1:1 by volume) at 1000° C. for one day, and then rapidly cool to 0° C., because the reaction speeds up. 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. The mixing ratio of Kohori et al. is Er2O:3, 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, it will be oxidized and become trivalent in an oxidizing atmosphere (for example, in the atmosphere), 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 0°C or rapidly drawn out into the atmosphere. The obtained ErGaMnO4 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 the reaction, and the stoichiometric number of the resulting compound was determined. ExamplesErbium oxide (Er2O3) powder with a purity of 99.9% or higher, manganese oxide (MnO) with a purity of 99.9% or higher, gallium oxide (with a purity of 99.9% or higher)
Ga2O3) powder was weighed at a molar ratio of 1:2:1, acetone was added in a mortar, and the mixture was thoroughly mixed 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 mm) 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 and rapidly cooled to room temperature. What was obtained was a hexagonal layered compound of ErGaMnO4. The properties of the crystal are the first
It was as shown in the table.

[Brief explanation of the drawing]

The drawing is a diagram of an ErGaMnO4 crystal of the present invention.

Claims (1)

[Claims] 1. A compound having a hexagonal layered structure represented by ErGaMnO_4. 2 Erbium oxide (Er_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 ErGaMnO_4. A method for producing a compound having