JP2011140427A - Method for producing multiple oxide powder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inexpensively and efficiently produce a multiple oxide expressed by a general formula; A<SB>1-X</SB>B<SB>X</SB>MO<SB>3+δ</SB>(in the formula, A is occupied by at least one kind of an element selected from rare earth elements; B is occupied by at least one kind of an element from calcium, strontium and barium; and M is occupied by at least one kind of an element from manganese and vanadium; 0≤x≤1.0; -0.5≤δ≤0.5). <P>SOLUTION: The method for producing multiple oxide includes a process of obtaining a precursor of the multiple oxide or directly crystalline multiple oxide by mixing and pulverizing a raw material using at least one kind of oxide, hydroxide and oxyhydroxide of the element occupying A site, at least one kind of oxide, hydroxide of the element occupying B site and at least one kind of oxide, hydroxide and oxyhydroxide of the element occupying M site as components, under an organic compound vapor atmosphere. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to an A _1-x B _x MO ₃₊ δ-type composite oxide useful as a magnetic material, a catalyst material, and an electrode material (wherein A is occupied by at least one element selected from rare earth elements, B Is occupied by at least one element of calcium, strontium and barium, M is occupied by at least one element of manganese and vanadium, and 0 ≦ x ≦ 1.0, −0.5 ≦ δ ≦ 0. It relates to the manufacturing method of 5).

Conventionally, A _1-x B _x MO ₃₊ δ-type composite oxide having a perovskite structure (wherein A is occupied by at least one element selected from rare earth elements, and B is at least one of calcium, strontium, and barium) It is occupied by one element, M is occupied by at least one element of manganese and vanadium, and 0 ≦ x ≦ 1.0, −0.5 ≦ δ ≦ 0.5) There has been known a “solid phase method” in which raw materials composed of oxides and carbonates of elements occupying sites are mixed and pulverized and reacted by heating at high temperature. However, in the solid phase method that requires heat treatment at a high temperature (1000 ° C. or higher) for a long time, the specific surface area of the perovskite-type composite oxide is reduced, and the obtained perovskite-type composite oxide includes other than the perovskite phase. There was a problem that many impurity phases and unreacted substances remained. In contrast to such conventional techniques, in recent years, the following manufacturing methods have been proposed.

Uniform composite oxide precursor by wet mixing and pulverizing at least one of oxides, hydroxides, oxide hydroxides and simple metals of each component in an aqueous solvent and separating the solid and liquid by filtration or the like A mechanochemical method for obtaining a crystalline perovskite structure compound by heat treatment at 500 ° C. to 1300 ° C. (Patent Documents 1 and 2);
La ₂ (CO ₃ ) ₃ · 8H ₂ O, MnO ₂ or V ₂ O ₃ and a flux component (a molten mixture of lithium carbonate and sodium carbonate) are uniformly mixed, and then about 650 in a carbon dioxide atmosphere. The molten carbonate method (Patent Document 3) in which crystalline LaMnO ₃ or LaVO ₃ having a perovskite structure is obtained by heating and holding at 0 ° C. for 48 hours and then washing with concentrated hydrochloric acid to remove carbonate and unreacted substances (Patent Document 3);
Add citric acid to a mixed aqueous solution of La (NO ₃ ) ₃ and NH ₄ VO ₃ , evaporate to dryness, pyrolyze at 600 ° C., and then heat-treat in air for 2 hours to further reduce LaVO ₄ in a reducing atmosphere. A thermal decomposition method of a complex citrate obtained by heat treatment at 1160 ° C. for 12 hours to obtain crystalline LaVO ₃ having a perovskite structure (Non-patent Document 1).

  Further, in addition to the above methods, as a general method, a complex oxide having a high specific surface area that does not contain an impurity phase, such as a coprecipitation method, a sol-gel method, an alkoxide method, or a hydrothermal synthesis method, is obtained. A method is mentioned. However, in any of these methods, a high-temperature heat treatment is necessary to synthesize a uniform powder, a step of removing by-products, etc. is required, and raw materials are expensive. There is an industrial disadvantage in terms of cost.

JP 2008-7394 A JP 2009-209029 A JP 2004-269327 A

Inorg. Chem. 47 (7), 2634

The present invention, efficient production at low cost, wherein the obtaining the _{A 1-x B x MO 3+} δ complex oxide precursor or directly crystalline _{A 1-x B x MO 3+} δ complex oxide It aims to provide a method.

As a result of diligent studies to solve such problems, the present inventors have found that at least one of oxides, hydroxides and oxide hydroxides of elements occupying the A site and elements occupying the B site. A raw material containing at least one of oxides and hydroxides of the above and at least one of oxides, hydroxides and oxide hydroxides of elements occupying M sites in an organic compound vapor by mixing and pulverizing treatment in, without generating by-products other than water and carbon dioxide from it, yet it is possible to omit the step of separating the solid-liquid, efficiently at a low cost, a _1-x The inventors have found that a precursor of a B _x MO ₃₊ δ-type composite oxide or a direct crystalline composite oxide can be produced, and the present invention has been completed.

  In the production method of the present invention, the element occupying the A site is at least one element of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, and Lu. When a composite oxide is targeted, in particular, a composite in which the element occupying the A site is La, the element occupying the B site is strontium, and the element occupying the M site is at least one of manganese and vanadium. This is suitable when an oxide is a target.

  Furthermore, the obtained precursor or crystalline composite oxide is preferably heat-treated at an appropriate temperature according to the intended use.

The mixing and pulverization treatment in the organic compound vapor atmosphere used in the production method of the present invention can be performed without the need for special equipment and expensive raw materials, and no by-products other than carbon dioxide and water are not generated. A by-product removal step is not required. Moreover, it is possible to omit the step of separating the solid and liquid. The precursor or crystalline composite oxide of the composite oxide obtained by such a mixed pulverization process is uniform and contains impurities that cause performance deterioration in various applications without being heat-treated or heat-treated once at a relatively low temperature. A high quality A _1-x B _x MO ₃₊ δ-type composite oxide can be produced efficiently at low cost. In addition, since the obtained composite oxide precursor or crystalline composite oxide is uniform and has a high specific surface area, it can be suitably used for addition to other compounds. Furthermore, an additive component can be suitably introduced into the composite oxide precursor or crystalline composite oxide obtained for the same reason.

2 is an X-ray diffraction pattern of the LaMnO ₃₊ δ crystalline composite oxide obtained in Example 1 due to heating changes. FIG. 4 is an X-ray diffraction pattern of the LaMnO ₃₊ δ crystalline composite oxide obtained in Example 2 by heating. The X-ray diffraction pattern by the heating change of the amorphous hydration precursor of SrMnO ₃ obtained in Example 3. X-ray diffraction pattern by heating the change of the resulting La _0.5 Sr _0.5 MnO ₃₊ δ crystalline composite oxide in Example 4. X-ray diffraction pattern by heating changes the amorphous hydrated precursor LaVO ₃ obtained in Example 5.

  Hereinafter, the raw materials used in the production method of the present invention, the mixing pulverization treatment in an organic compound vapor atmosphere, the heat treatment methods and conditions, and the like will be described in detail.

A _1-x B _x MO ₃₊ δ Type Composite Oxide A composite oxide which is an object of the present invention is represented by the general formula A _1-x B _x MO ₃₊ δ. In the formula, A is occupied by at least one element selected from rare earth elements, B is occupied by at least one element selected from calcium, strontium, and barium, and M is at least one element selected from manganese and vanadium. Occupied with elements. x is a number satisfying 0 ≦ x ≦ 1.0. Further, δ represents an excess amount of oxygen or an oxygen deficiency that varies depending on the composition (B site addition amount, M valence change, etc.) and heat treatment conditions (temperature, atmosphere, etc.). It is a number that satisfies 5 ≦ δ ≦ 0.5.

  In the production method of the present invention, the element occupying the A site is at least one element of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, and Lu. In particular, industrially useful composite oxides such as those in which the element occupying the A site is La, the element occupying the B site is strontium, and the element occupying the M site is manganese and / or vanadium. It is suitable for the target.

The A site, B site, and M site of the A _1-x B _x MO ₃₊ δ-type composite oxide are mixed and pulverized in an organic compound vapor atmosphere, a precursor before heat treatment, and a crystalline composite oxide. In addition, an element other than the elements described above can be added and substituted for solid solution. Further, the manufacturing method of the present invention is applied to A ₁ in which the molar ratio [(A + B) / M] of “the above-mentioned element contained in the A site and B site” and “the above-mentioned element contained in the M site” is _1. It is not limited only to _-x B _x MO ₃₊ δ type complex oxide.

As raw material components of rare earth elements occupying the raw material A site [Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Lu], oxides of these rare earth elements [A ₂ O ₃ , AO ₂ etc.], hydroxides [A (OH) ₃ , A (OH) ₄ etc.], oxide hydroxides [AO (OH) etc.]. In addition, the above compounds include those containing crystal water [A ₂ O ₃ · nH ₂ O, AO ₂ · nH ₂ O, A (OH) ₃ · nH ₂ O, A (OH) ₄ · nH ₂ O, etc. , N is a positive number], non-stoichiometric oxide hydrates [A ₂ O ₃ .XH ₂ O, AO ₂ .XH ₂ O, etc., X is an arbitrary positive number] Those not containing hydrate and those not containing hydrates are desirable, and oxides are more desirable than hydroxides and oxide hydroxides, but the above compounds are not limited to oxides. These substances may be crystalline or amorphous. Any one of the rare earth element occupying the A site may be used alone, or two or more may be used in combination.

As raw material components of elements occupying the B site [calcium (Ca), strontium (Sr), barium (Ba)], oxides of these elements [BO etc.], hydroxides [B (OH) ₂ etc.] Can be mentioned. The above compound contains water of crystallization [BO.nH ₂ O, B (OH) ₂ .nH ₂ O, etc., n is a positive number], non-stoichiometric oxide hydrate [BO · XH ₂ O and the like, and X is an arbitrary positive number], but those not containing water of crystallization and those not hydrated are desirable, and oxides are more desirable than hydroxides and oxide hydroxides. The above compounds are not limited to oxides. These substances may be crystalline or amorphous. Any one of the rare earth element occupying the A site may be used alone, or two or more may be used in combination.

As raw material components of elements occupying M sites [manganese (Mn), vanadium (V)], oxides of these elements [M ₂ O ₃ , M ₃ O ₄ , MO ₂ , M ₂ O ₅ etc.], water Oxides [M (OH) ₃ , M (OH) ₄ , M (OH) ₅ etc.], oxide hydroxides [MO (OH), MO ₂ (OH), MO (OH) ₂ etc.] can be mentioned. The above compound contains crystal water [M ₂ O ₃ · nH ₂ O, M ₃ O ₄ · nH ₂ O, MO ₂ · nH ₂ O, M (OH) ₃ · nH ₂ O, M ( OH) ₄ · nH ₂ O, M (OH) ₅ · nH ₂ O, etc., n is a positive number], non-stoichiometric oxide hydrate [M ₂ O ₃ · XH ₂ O, M ₃ O ₄ · XH ₂ O, MO ₂ .XH ₂ O, M ₂ O ₅ .XH ₂ O, etc., where X is an arbitrary positive number], but those not containing water of crystallization and those not hydrated are desirable, An oxide is more preferable than a hydroxide or an oxide hydroxide, but the above compounds are not limited to oxides. These substances may be crystalline or amorphous. Any one of the raw material components of the element occupying the M site may be used alone, or two or more may be used in combination.

The particle size of the material used as the raw material is preferably 100 μm or less, more preferably 50 μm or less, and still more preferably 10 μm or less.
Moreover, the compounding quantity of each component of a raw material should just make the quantitative ratio in the raw material of each element which occupies A site, B site, and M site the same as the quantitative ratio in the target complex oxide.

Process of mixing and pulverizing in organic compound vapor atmosphere The mixing and pulverizing process of raw materials in the present invention is generally carried out in an organic compound vapor (gas) atmosphere using a mixing and pulverizing machine. The organic compound vapor (gas) in the present invention is put in a pulverization container together with raw materials. In a normal case, the temperature in the grinding container is about 20 ° C. (room temperature) to about 80 ° C. due to frictional heat of the grinding media and the like. If the mixing pulverizer is equipped with a cooling device, the temperature in the pulverization container is 20 ° C. (room temperature) to minus several tens of degrees C. If the mixing pulverizer is capable of introducing heated gas, the temperature in the pulverization container is 100 ° C. or higher. It is also possible to make it. Any organic compound that becomes vapor (gas) in the pulverization vessel and promotes the reaction with the raw material can be used without particular limitation. Examples of organic compounds that can be vaporized in these temperature ranges include hydrocarbon gases, low-boiling ketones and alcohols, and examples thereof include the following organic compounds.
Hydrocarbon gas: methane gas (boiling point: -161.5 ° C), ethane gas (boiling point: -89.0 ° C),
Propane gas (boiling point: −42.7 ° C.), butane gas (boiling point: −0.5 ° C.), etc. Ketones: acetone (boiling point: 56.1 ° C.), methyl ethyl methone (boiling point: 79.6 ° C.),
Diethyl ketone (boiling point: 101.5 ° C), etc. Alcohols: methanol (boiling point: 64.5 ° C), ethanol (boiling point: 78.3 ° C),
1-propanol (boiling point; 97.2 ° C.), 1-butanol (boiling point; 117.
Aldehydes: formaldehyde (boiling point; -19.3 ° C), acetaldehyde (boiling point; 20
.2 ℃)

Any one of these organic compounds may be used alone, or two or more thereof may be used in combination. Further, it may be used by diluting with an inert gas such as N ₂ , He, or Ar which is not related to the reaction. Even when the container temperature is lower than the boiling point of the organic compound, the saturated vapor amount of the organic compound at the container temperature is, for example, the case where MnO ₂ and V ₂ O ₅ are used as raw materials. There is no problem if the amount is sufficient for the reaction. Further, even if the organic compound vapor in the pulverization vessel is equal to or lower than the saturated vapor pressure, the amount of the organic compound vapor supplied into the pulverization vessel is, for example, more than an amount sufficient for the raw material reduction reaction as shown below. Absent. Further, when the heat treatment step after the pulverization is performed in an inert atmosphere or a reducing atmosphere, for example, the raw material MnO ₂ or V ₂ O ₅ may not be completely reduced to Mn ₂ O ₃ or V ₂ O _3. There may not be. In this case, the vapor amount of the organic compound supplied into the pulverization vessel may be about 1/2 of the theoretical amount of the reduction reaction shown below. That is, the supply amount of the organic compound vapor may be finely adjusted as appropriate depending on the desired crystallinity of the mixed pulverized product.
For example, when the organic compound vapor is acetone:
CH ₃ COCH ₃ + 16MnO ₂ → 3CO ₂ + 3H ₂ O + 8Mn ₂ O ₃
CH ₃ COCH ₃ + 4V ₂ O ₅ → 3CO ₂ + 3H ₂ O + 4V ₂ O ₃
For example, when the organic compound vapor is ethanol:
CH ₃ CH ₂ OH + 12MnO ₂ → 2CO ₂ + 3H ₂ O + 6Mn ₂ O ₃
CH ₃ CH ₂ OH + 3V ₂ O ₅ → 2CO ₂ + 3H ₂ O + 3V ₂ O ₃

  A sufficient amount of organic compound vapor (gas) for the reaction may be supplied into the pulverization vessel, but an organic compound having a boiling point of about 20 ° C. (room temperature) to about 80 ° C., which is the temperature in the normal pulverization vessel. It can be used suitably. Further, it is desirable that all organic compounds are vapor (gas) in the pulverization vessel, but a part of them may remain as a liquid as long as the amount is small.

The organic compound vapor may be prepared in advance as vapor and supplied into the pulverization container before the start of the mixing and pulverization process. However, the organic compound is put into the pulverization container in a liquid state and mixed and pulverized. You may vaporize using the heat_generation | fever which arises in a process. Further, in a continuous mixing and pulverizing machine, the organic compound vapor may be mixed with a carrier gas such as an inert gas such as N ₂ , He, or Ar which is irrelevant to the reaction.

  The mixing pulverizer may be any material that can mechanically pulverize and grind the raw material. For example, the raw material and a pulverizing medium (rod, cylinder, ball, bead, etc.) are placed in a pulverization container. A ball mill such as a rolling ball mill, a vibration ball mill, a stirring ball mill, or a planetary ball mill that pulverizes the raw material by stirring is suitable. Crushers with such a ball mill as a continuous type (for example, “SC Mill” manufactured by Nihon Coke Industries Co., Ltd., “Dino Mill” manufactured by Shinmaru Enterprises Co., Ltd., “Lady Mill” manufactured by Imex Co., Ltd.), A ball mill that can use very small balls (beads) having a diameter of 1 mm or less is also recommended. Furthermore, an air circulation type continuous pulverizer that does not use a pulverizing medium (for example, “Cross Jet Mill” manufactured by Kurimoto Seiko Co., Ltd.) can also be used.

As balls (beads) which are typical grinding media, ZrO ₂ (zirconia), Si ₃ N ₄ (silicon nitride), SiC (silicon carbide), WC (tungsten carbide), having a diameter of about 0.1 to 10 mm, A material made of a material such as steel can be used. For example, a zirconia ball “YTZ” (registered trademark) manufactured by Tosoh Corporation is preferable.

  What is necessary is just to adjust the process conditions of mixing and grinding appropriately according to the kind of mixing and grinding machine. For example, when using a planetary ball mill, it is preferable that the filling amount of balls (beads) as a grinding medium is 15 to 60 mL and the filling amount of the raw material is 1 to 30 mL per 100 mL of the container volume. The input amount of the organic compound vapor is as described above, and may be appropriately adjusted depending on the type of the organic compound. Further, the revolution speed of the planetary ball mill is usually 1 to 10 Hz, preferably 4 to 6 Hz, and the processing time for the mixing and grinding is preferably 1 to 10 hours.

  This is a method for recovering the mixed pulverized product, but the product obtained by the mixed pulverization treatment contains a small amount of water produced as a by-product of the reaction. Can do. It is only necessary to separate the powdered mixed pulverized product and the pulverizing medium (such as pulverized balls) with a sieve or the like.

Heat treatment step By collecting the mixed and pulverized product as described above, a powdery precursor of A _1-x B _x MO ₃₊ δ-type composite oxide or a crystalline composite oxide can be obtained.

  The precursor or crystalline composite oxide obtained may be dried by any method such as ordinary ventilation drying or vacuum drying, but drying in a vacuum or an inert atmosphere is preferred. Although drying temperature is not specifically limited, 50-300 degreeC is preferable.

By heat-treating (pre-calcining) the precursor or crystalline composite oxide thus obtained, the precursor is crystallized into an A _1-x B _x MO ₃₊ δ-type composite oxide, and has already been crystallized. The A _1-x B _x MO ₃₊ δ-type composite oxide has improved crystallinity (crystallinity).

The heat treatment conditions (temperature, time, etc.) can be adjusted as appropriate according to the target A _1-x B _x MO ₃₊ δ-type composite oxide (crystallinity, etc.). For example, the temperature of the heat treatment is preferably room temperature to 1300 ° C. The heat treatment may be performed in the air or in an inert gas atmosphere such as argon or nitrogen, but the target A _1-x B _x MO ₃₊ δ-type complex oxide crystal system (crystal It is preferable to select appropriately depending on the structure.

The crystallinity (crystal system, crystal structure, crystallinity, etc.) of the A _1-x B _x MO ₃₊ δ-type composite oxide can be confirmed by an X-ray diffraction pattern.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the scope of the present invention is not limited to these examples.

Example 1 LaMnO ₃₊ δ
To a planetary ball mill (stainless steel pot, volume 420 mL) manufactured by Kurimoto Seiko Co., Ltd., 10.1 g of raw material powder La ₂ O _3, 5.4 g of electrolytic MnO ₂ and 0.3 mL of acetone were added to a 2 mmφYTZ ^(R) ball (Tosoh Corporation ^). The product was filled with 168 mL, and the atmosphere inside the container was replaced with argon gas, and then subjected to a revolution and a rotation speed of 6 Hz for 3 hours. After the treated product was collected, vacuum drying was performed at 85 ° C. for 12 hours to obtain a LaMnO ₃₊ δ crystalline composite oxide.

FIG. 1 shows an X-ray diffraction pattern of the LaMnO _{3 +} δ crystalline composite oxide and the LaMnO _{3 +} δ crystalline composite oxide, which were heat-treated at 400 ° C. to 1000 ° C. for 1 hour in the air. . All were single phases of a perovskite structure of crystalline LaMnO ₃₊ δ composite oxide. The specific surface area value is 1 at 5.5m ² / g, 400 ℃ at 3.8 m ² / g, at 600 ℃ 3.6m ² / g, at ^{800 ℃ 2.5m 2 / g, 1000} ℃ at 85 ° C. dry product 0.6 m ² / g.

[Example 2] LaMnO ₃₊ δ
To a planetary ball mill (stainless steel pot, volume 420 mL) manufactured by Kurimoto Seiko Co., Ltd., 10.1 g of raw material powder La ₂ O _3, 5.4 g of electrolytic MnO ₂ and 0.3 mL of ethanol were added to a 2 mmφYTZ ^(R) ball (Tosoh Corporation ^). The product was filled with 168 mL, and the atmosphere inside the container was replaced with argon gas, and then subjected to a revolution and a rotation speed of 6 Hz for 3 hours. After the treated product was collected, vacuum drying was performed at 85 ° C. for 12 hours to obtain a LaMnO ₃₊ δ crystalline composite oxide.

FIG. 2 shows an X-ray diffraction pattern of the LaMnO ₃₊ δ crystalline composite oxide and the LaMnO ₃₊ δ crystalline composite oxide subjected to heat treatment at 400 ° C. to 1000 ° C. for 1 hour in the air. . All were single phases of a perovskite structure of crystalline LaMnO ₃₊ δ composite oxide. The specific surface area value is 1 at 3.1m ² / g, 1000 ℃ at 4.1m ² / g, 800 ℃ at 5.8m ² / g, 400 ℃ at 5.3m ² / g, 600 ℃ at 85 ° C. dry product It was 3 m ² / g.

Example 3 SrMnO ₃
9.6 g of Sr (OH) ₂ produced by vacuum drying the raw material powder Sr (OH) ₂ .8H ₂ O at 100 ° C. for 12 hours on a planetary ball mill (stainless steel pot, volume 420 mL) manufactured by Kurimoto Steel Works and electrolytic MnO ₂ 6.8 g and 0.3 mL of acetone were filled together with 168 mL of ₂ mmφYTZ ^(R) balls (manufactured by Tosoh Corporation), and the atmosphere inside the container was replaced with argon gas, and then the revolution and rotation speed were 6 Hz for 3 hours. Was processed. After the treated product was collected, vacuum drying was performed at 85 ° C. for 12 hours to obtain an amorphous hydrated precursor of SrMnO ₃ composite oxide.

Xr of the amorphous hydration precursor of the SrMnO ₃ composite oxide and the amorphous hydration precursor of the SrMnO ₃ composite oxide subjected to heat treatment at 700 ° C. to 1000 ° C. for 1 hour in the atmosphere. A line diffraction pattern is shown in FIG. A single phase having a perovskite-like structure of crystalline SrMnO ₃ composite oxide was obtained by heat treatment at 700 ° C. or higher. The specific surface area value was 3.8 m ² / g at 4.8m ² / g, 1000 ℃ at 6.3m ² / g, 800 ℃ at 4.1m ² / g, 700 ℃ at 85 ° C. dried product.

Example 4 La _0.5 Sr _0.5 MnO ₃₊ δ
It was produced by vacuum drying raw material powder La ₂ O ₃ 5.7 g and Sr (OH) ₂ .8H ₂ O at 100 ° C. for 12 hours in a planetary ball mill (stainless steel pot, volume 420 mL) manufactured by Kurimoto Seiko Co., Ltd. 4.2 g of Sr (OH) _2, 6.0 g of electrolytic MnO ₂ , and 1.0 mL of acetone were filled together with 168 mL of ₂ mmφYTZ ^(R) balls (manufactured by Tosoh Corporation), and the atmosphere inside the container was replaced with argon gas. Then, the process for 3 hours was performed at revolution and rotation speed 6Hz. After recovering the treated product, vacuum drying was performed at 85 ° C. for 12 hours to obtain a crystalline composite oxide of La _0.5 Sr _0.5 MnO ₃₊ δ.

The La _0.5 Sr _0.5 MnO ₃₊ δ crystalline composite oxide and the La _0.5 Sr _0.5 MnO ₃₊ δ crystalline composite oxide were heat-treated at 400 ° C. to 1000 ° C. for 1 hour in the atmosphere. A line diffraction pattern is shown in FIG. All were single phases of a perovskite structure of crystalline La _0.5 Sr _0.5 MnO ₃₊ δ composite oxide. The specific surface area value is 1 at 3.3m ² / g, 1000 ℃ at 13.3m ² / g, 800 ℃ at 5.9m ² / g, 400 ℃ at 6.1m ² / g, 600 ℃ at 85 ° C. dry product It was 4 m ² / g.

[Example 5] LaVO ₃
To a planetary ball mill (stainless steel pot, volume 420 mL) manufactured by Kurimoto Seiko Co., Ltd., 10.3 g of raw material powder La ₂ O _3, 5.7 g of V ₂ O ₅ , and 1.0 mL of acetone were added to a 2 mmφYTZ ^(R) ball ( After filling with 168 mL of Tosoh Corp. and substituting the atmosphere inside the container with argon gas, it was subjected to a revolution and a rotation speed of 6 Hz for 3 hours. After the treated product was recovered, vacuum drying was performed at 85 ° C. for 12 hours to obtain an amorphous hydrated precursor of LaVO ₃ .

FIG. 5 shows an X-ray diffraction pattern of the LaVO ₃ amorphous hydration precursor and the LaVO ₃ amorphous hydration precursor subjected to heat treatment at 300 ° C. to 1000 ° C. for 1 hour in argon. . It was a single phase of a perovskite structure of crystalline LaVO ₃ composite oxide by heating at 800 ° C. or higher. The specific surface area when heat-treated at 800 ° C. for 1 hour was 6.4 m ² / g.

Claims (4)

General formula A _1-x B _x MO ₃₊ δ (where A is occupied by at least one element selected from rare earth elements, and B is occupied by at least one element selected from calcium, strontium, and barium) , M is a method for producing a composite oxide which is occupied by at least one element of manganese and vanadium and is represented by 0 ≦ x ≦ 1.0 and −0.5 ≦ δ ≦ 0.5) ,
At least one of oxides, hydroxides and oxide hydroxides of elements occupying A site, at least one of oxides and hydroxides of elements occupying B site, and elements occupying M site The precursor of the composite oxide or the direct crystallinity is obtained by mixing and pulverizing a raw material containing at least one of oxides, hydroxides, and oxide hydroxides in an organic compound vapor atmosphere. A method for producing an A _1-x B _x MO ₃₊ δ-type composite oxide, comprising a step of obtaining a composite oxide. The rare earth element occupying the A site is at least one element of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, and Lu. The method for producing an A _1-x B _x MO ₃₊ δ-type composite oxide according to claim 1. The rare earth element occupying the A site is La, the element occupying the B site is strontium, and the element occupying the M site is at least one element of manganese and vanadium. A method for producing the A _1-x B _x MO ₃₊ δ-type composite oxide according to ₁ . A crystalline A _1-x B _x MO comprising a step of heat-treating a precursor of the composite oxide or the crystalline composite oxide obtained by the production method according to claim 1. Method for producing ₃₊ δ-type complex oxide.

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