JP5205904B2 - Method for producing metal oxide film and laminate - Google Patents

Description

  The present invention relates to a method for producing a metal oxide film capable of obtaining a metal oxide film whose porosity is changed stepwise or continuously by a simple method, and a laminate including the metal oxide film. It is.

  Conventionally, it has been known that metal oxide films exhibit various excellent physical properties. Taking advantage of these properties, metal oxide films have been used in a wide range of fields such as transparent conductive films, optical thin films, and fuel cell electrolytes. As a method for producing such a metal oxide film, for example, a sol-gel method, a sputtering method, a CVD method, a PVD method, a printing method and the like are known.

  On the other hand, a spray pyrolysis method has been proposed as another method for obtaining such a metal oxide film (Patent Document 1 and Patent Document 2). The spray pyrolysis method is a method in which a metal oxide film is obtained by spraying a solution containing a metal source constituting the metal oxide film onto a high temperature substrate, and a substrate heated to about 500 ° C. is usually used. Since it is used, the solvent instantly evaporates and the metal source undergoes a thermal decomposition reaction, so that the metal oxide film can be obtained in a short and simplified process.

As a study of such spray pyrolysis method, for example, in Patent Document 1, hydrogen peroxide or aluminum acetylacetonate is added to a solution containing a TiO ₂ precursor to prepare a raw material solution, and the temperature is about 500 ° C. A method is disclosed in which a TiO ₂ precursor is thermally decomposed into TiO ₂ by intermittently spraying the raw material solution onto a substrate maintained at a high temperature to obtain a porous TiO ₂ thin film on the substrate. Further, for example, Patent Document 2 is a method for obtaining a porous TiO ₂ thin film by a pyrolysis spray method as in Patent Document 1, but by adding a solution obtained by adding a soluble titanium compound to a raw material solution, TiO ₂ is obtained. ₍₂₎ The adhesion between the thin film and the substrate was improved.

  In addition, the porous metal oxide film can be used for, for example, a gas or liquid reforming film, an optical thin film, a heat radiating / heat insulating member, etc. The porosity is preferably small, that is, dense, and preferably has a large porosity on the surface opposite to the substrate side surface. As described above, a metal oxide film whose porosity is changed stepwise or continuously in the stacking direction or the like is desired.

  For example, in Patent Document 3, a first component made of a metal or a metal compound and a second component made of a metal compound different from the first component are mixed and dispersed with each other on the substrate. A method for forming a porous metal compound thin film, comprising: forming a mixed thin film whose composition ratio with two components changes in the film thickness direction; and then selectively removing the first component in the mixed thin film. It is disclosed. However, this method is a method in which a mixed thin film having a different composition ratio between the first component and the second component is formed, and the first component is removed from the mixed thin film. There was a problem that there was a lot of material loss.

  In Patent Document 4, a metal oxide dispersion containing metal oxide fine particles and a solvent as essential components is sprayed and applied onto a sheet-like electrode, and dried to form a metal oxide porous film. A method for producing a photoactive electrode for a dye-sensitized solar cell is disclosed.

JP 2002-145615 A JP 2003-176130 A JP-A-2005-39013 Japanese Patent Laid-Open No. 2002-324591

  The present invention has been made in view of the above problems, and provides a method for producing a metal oxide film that can obtain a metal oxide film whose porosity has been changed stepwise or continuously by a simple method. The main purpose is to do.

  As a result of previous research, the present inventor has developed a solution in which a metal source such as a metal salt or an organometallic compound is dissolved in a solvent by spraying the heated substrate with a dense metal on the substrate. It has been found that an oxide film can be formed. On the other hand, in the process of completing the present invention, the present inventors sprayed a solution for forming a metal oxide film containing two or more kinds of metal sources having different metal elements onto a heated substrate, thereby producing a porous material. It has been found that a high quality metal oxide film can be formed. This phenomenon is considered to be because two or more kinds of metal sources having different metal elements grow crystals so as to repel each other when the metal oxide film is formed.

  The present invention has been made based on this finding, and by changing the ratio of two or more kinds of metal sources having different metal elements over time, the metal oxide whose porosity has been changed stepwise or continuously. The inventors have found that a film can be formed and have completed the present invention.

  That is, in the present invention, two or more kinds of metal sources having different metal elements are used, and the metal oxide film forming solution having different metal source mole fractions of the two or more kinds of metal sources is used as the metal source mole fraction. A metal oxide film characterized by forming a metal oxide film having a changed porosity on the substrate by contacting the substrate heated to a temperature equal to or higher than the metal oxide film forming temperature while changing A method for manufacturing a material film is provided.

  According to the present invention, a metal oxide film whose porosity has been changed stepwise or continuously can be simplified by bringing the metal oxide film forming solution into contact with a heated substrate while changing the ratio of the metal source. Can get to.

  In the said invention, it is preferable that the said metal source is a metal salt or an organometallic compound. This is because a metal oxide film whose porosity is changed stepwise or continuously can be obtained by a simple method.

  In the said invention, it is preferable that the said solution for metal oxide film formation has a copper containing metal source containing a copper element, and a zinc containing metal source containing a zinc element. This is because a metal oxide film containing a porous component composed of copper oxide and zinc oxide can be obtained.

  In the above invention, the metal oxide film forming solution has a nickel-containing metal source containing a nickel element, a zirconium-containing metal source containing a zirconium element, and an yttrium-containing metal source containing an yttrium element. It is preferable. This is because a metal oxide film containing a porous component composed of nickel oxide and YSZ can be obtained.

  In the said invention, it is preferable that the said solution for metal oxide film formation has a cobalt containing metal source containing a cobalt element, and an iron containing metal source containing an iron element. This is because a metal oxide film containing a porous component composed of cobalt oxide and iron oxide can be obtained.

  In the said invention, it is preferable that the said solution for metal oxide film formation has a titanium containing metal source containing a titanium element and a lanthanum containing metal source containing a lanthanum element. This is because a metal oxide film containing a porous component composed of titanium oxide and lanthanum oxide can be obtained.

  In the said invention, it is preferable that the said solution for metal oxide film formation has a cerium containing metal source containing a cerium element, and a calcium containing metal source containing a calcium element. This is because a metal oxide film containing a porous component composed of cerium oxide and calcium oxide can be obtained.

  In the said invention, it is preferable that the said solution for metal oxide film formation has an indium containing metal source containing an indium element, and a vanadium containing metal source containing a vanadium element. This is because a metal oxide film containing a porous component composed of indium oxide and vanadium oxide can be obtained.

  In the said invention, it is preferable that the said solution for metal oxide film formation has a tantalum containing metal source containing a tantalum element and a gadolinium containing metal source containing a gadolinium element. This is because a metal oxide film containing a porous component composed of tantalum oxide and gadolinium oxide can be obtained.

  In the said invention, it is preferable that the said solution for metal oxide film formation has a chromium containing metal source containing a chromium element, and a molybdenum containing metal source containing a molybdenum element. This is because a metal oxide film containing a porous component composed of chromium oxide and molybdenum oxide can be obtained.

  In the said invention, it is preferable that the said solution for metal oxide film formation has a tungsten containing metal source containing a tungsten element and an aluminum containing metal source containing an aluminum element. This is because a metal oxide film containing a porous component composed of tungsten oxide and aluminum oxide can be obtained.

  Moreover, in this invention, it is a laminated body which has a base material and the metal oxide film formed on the said base material, Comprising: The said metal oxide film is 2 or more types of metal oxides from which a metal element differs And a porous body in which the porosity of the metal oxide film is continuously changed.

  According to this invention, since it has a metal oxide film | membrane whose porosity changed continuously, it can be set as the laminated body applicable to various uses.

  In this invention, there exists an effect that the metal oxide film from which the porosity changed stepwise or continuously can be obtained by a simple method.

  Hereinafter, the manufacturing method of the metal oxide film of the present invention and the laminate will be described in detail.

A. First, a method for producing a metal oxide film of the present invention will be described. The method for producing a metal oxide film of the present invention uses two or more types of metal sources having different metal elements, and the metal oxide film forming solution having different metal source molar fractions of the two or more types of metal sources is used as described above. Forming a metal oxide film with changed porosity on the substrate by contacting the substrate heated to a temperature equal to or higher than the metal oxide film formation temperature while changing the metal source mole fraction. It is a feature.

  According to the present invention, a metal oxide film whose porosity has been changed stepwise or continuously can be simplified by bringing the metal oxide film forming solution into contact with a heated substrate while changing the ratio of the metal source. Can get to. Note that, as described above, when a metal oxide film containing two or more types of metal sources having different metal elements is applied to a heated substrate, the metal oxides having different metal elements grow so as to repel each other. A porous metal oxide film is obtained. In the present invention, it is possible to obtain a metal oxide film whose porosity is changed stepwise or continuously by changing the ratio of the two or more kinds of metal sources stepwise or continuously. Moreover, according to the present invention, a metal oxide film having a changed porosity can be obtained by a simple method of bringing a metal oxide film forming solution into contact with a heated substrate.

  Next, the manufacturing method of the metal oxide film of this invention is demonstrated using drawing. FIG. 1 is an explanatory view showing an example of a method for producing a metal oxide film of the present invention. The metal oxide film manufacturing method shown in FIG. 1 uses a metal source A and a metal source B having different metal elements, a metal oxide film forming solution A containing only the metal source A, a metal source A, and a metal source. A solution for forming a metal oxide film containing B (A + B) was prepared, and then the substrate 1 heated to a temperature equal to or higher than the metal oxide film formation temperature was used using the spray device 2 to prepare the solution A and the solution In this method, a metal oxide film is formed on the substrate 1 by sequentially spraying (A + B). By using the above method, a metal comprising a dense metal oxide layer derived from the metal source A and a porous metal oxide layer derived from the metal source A and the metal source B from the substrate surface side. An oxide film can be obtained. Note that the obtained metal oxide film can be referred to as a metal oxide film whose porosity changes stepwise in the stacking direction.

  Moreover, FIG. 2 is explanatory drawing which shows the other example of the formation method of the metal oxide film of this invention. The metal oxide film manufacturing method shown in FIG. 2 uses a metal source A and a metal source B having different metal elements, and contains only a metal oxide film forming solution A containing only the metal source A and only the metal source B. A base plate 1 heated to a temperature equal to or higher than the metal oxide film forming temperature, and using the spray device 2 to spray only the solution A at first. Next, a method of forming a metal oxide film on the substrate 1 by gradually increasing the flow rate of the solution B with respect to the solution A and performing spraying. By using the above method, a metal oxide film having a dense base material surface and continuously increasing porosity toward the opposite side can be obtained.

  In the present invention, the “metal oxide film formation temperature” refers to a temperature at which a metal element contained in a metal source can combine with oxygen and form a metal oxide film on a substrate. It varies greatly depending on the type of metal source such as salt and organometallic compound and the composition of the metal oxide film forming solution such as solvent. In the present invention, such “metal oxide film formation temperature” can be measured by the following method. That is, the lowest base material on which a metal oxide film can be formed by preparing a solution for forming a metal oxide film that actually contains a desired metal source and changing the heating temperature of the base material to make contact Measure the heating temperature. This minimum substrate heating temperature can be set as the “metal oxide film forming temperature” in the present invention. At this time, whether or not the metal oxide film is formed is usually judged from the result obtained from an X-ray diffraction apparatus (Rigaku, RINT-1500). In the case of an amorphous film having no crystallinity, photoelectron spectroscopy is performed. It shall judge from the result obtained from the analyzer (the product made by VG Scientific, ESCALAB 200I-XL).

In particular, in the present invention, as shown in FIG. 1 described above, when using a plurality of metal oxide film forming solutions in which the metal source mole fraction is changed stepwise, the heating temperature of the substrate is set to The temperature may be changed as appropriate so as to be equal to or higher than the metal oxide film formation temperature corresponding to the metal oxide film formation solution, but usually the highest metal oxidation among the plurality of metal oxide film formation solutions. The substrate heating temperature is set to be equal to or higher than the physical film formation temperature, and the metal oxide film is formed at a constant temperature. On the other hand, as shown in FIG. 2 described above, when a metal oxide film forming solution in which the metal source molar fraction continuously changes is used, the highest metal is usually selected from the metal oxide film forming solutions. The heating temperature of the substrate is set to be equal to or higher than the oxide film formation temperature, and the metal oxide film is formed while maintaining the temperature constant.
Hereafter, the manufacturing method of the metal oxide film of this invention is demonstrated in detail for every structure.

1. Metal Oxide Film Forming Solution First, the metal oxide film forming solution used in the present invention will be described. In the present invention, two or more metal sources having different metal elements are used, and the metal oxide film forming solution having different metal source mole fractions of the two or more metal sources is changed in the metal source mole fraction. Meanwhile, a metal oxide film having a changed porosity is obtained by contacting with a heated substrate. The “metal source molar fraction” means a ratio of a specific metal source based on the mole to all metal sources contained in the metal oxide film forming solution.

In the present invention, by using a metal oxide film forming solution in which two or more kinds of metal sources having different metal elements are used and the metal source molar fraction of the metal source is changed, the metal oxide having a changed porosity is used. A material film is obtained. In the present invention, it is preferable to use a metal oxide film forming solution having a metal source mole fraction of 70% or less of the metal source most contained in the metal oxide film forming solution at least once. This is because it is possible to prevent the specific metal element from being excessively present with respect to the other metal element, and it is possible to prevent the other metal oxide crystal from being included in the specific metal oxide crystal. As a result, it is possible to obtain a porous metal oxide film in which different kinds of metal elements are crystal-grown so as to repel each other, the average pore diameter is small, and the surface area is high. The metal source molar fraction is preferably 70% or less, more preferably 60% or less, and still more preferably in the range of 40% to 60%.
The method for changing the metal source molar fraction will be described in detail in “3. Method for changing the metal source molar fraction” described later.

  Hereinafter, the metal source contained in the metal oxide film forming solution will be described first, and then the oxidizing agent, reducing agent, solvent, and additive will be described.

(1) Metal source In the present invention, two or more kinds of metal sources having different metal elements are used. The metal source used in the present invention is usually a metal salt or an organometallic compound. In addition, the combination of the metal sources is not particularly limited as long as it is a combination of metal sources having different metal elements, and can be arbitrarily selected. This is because, when a metal source having a different metal element is used, when a metal oxide film is formed, crystals grow so as to repel each other and a porous metal oxide film can be formed.
Hereinafter, a metal source used in the present invention will be described first, and then a combination of metal sources will be described.

  The metal element constituting the metal source is not particularly limited as long as it can form a metal oxide film. For example, Mg, Al, Si, Ti, V, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Ag, In, Sn, Ce, Sm, Pb, La, Hf, Sc, Gd, Ta, Ca, Cr, Ga, Sr, Nb, Mo, Pd, Sb, Te, Ba, W, etc. can be mentioned.

As described above, the metal source is usually a metal salt or an organometallic compound.
The metal salt is not particularly limited as long as it can form a metal oxide film. For example, a chloride, nitrate, sulfate, perchlorate, acetic acid containing the metal element is used. A salt, a phosphate, a bromate, etc. can be mentioned. Among these, in the present invention, it is preferable to use chloride, nitrate, and acetate. This is because these compounds are easily available as general-purpose products.

  On the other hand, the organometallic compound is not particularly limited as long as it can form a metal oxide film, and specifically, magnesium diethoxide, aluminum acetylacetonate, calcium acetylacetate. Narate dihydrate, calcium di (methoxyethoxide), calcium gluconate monohydrate, calcium citrate tetrahydrate, calcium salicylate dihydrate, titanium lactate, titanium acetylacetonate, tetraisopropyl titanate, tetra Normal butyl titanate, tetra (2-ethylhexyl) titanate, butyl titanate dimer, titanium bis (ethylhexoxy) bis (2-ethyl-3-hydroxyhexoxide), diisopropoxytitanium bis (triethanolaminate), dihydro Cibis (ammonium lactate) titanium, diisopropoxy titanium bis (ethyl acetoacetate), titanium peroxocitrate ammonium tetrahydrate, dicyclopentadienyl iron (II), iron lactate (II) trihydrate, iron ( III) Acetylacetonate, Cobalt (II) Acetylacetonate, Nickel (II) Acetylacetonate dihydrate, Copper (II) Acetylacetonate, Copper (II) Dipivaloylmethanate, Copper (II) ethylacetoacetate (II) ), Zinc acetylacetonate, zinc lactate trihydrate, zinc salicylate trihydrate, zinc stearate, strontium dipivaloylmethanate, yttrium dipivaloylmethanate, zirconium tetra-n-butoxide, zirconium ( IV) Ethoxide, zirconium normal propylate, zirconium normal butyrate, Luconium tetraacetylacetonate, zirconium monoacetylacetonate, zirconium acetylacetonate bisethylacetoacetate, zirconium acetate, zirconium monostearate, penta-n-butoxyniobium, pentaethoxyniobium, pentaisopropoxyniobium, tris (acetylacetate Nato) indium (III), indium (III) 2-ethylhexanoate, tetraethyltin, dibutyltin oxide (IV), tricyclohexyltin (IV) hydroxide, lanthanum acetylacetonate dihydrate, tri (methoxyethoxy) Lanthanum, pentaisopropoxy tantalum, pentaethoxy tantalum, tantalum (V) ethoxide, cerium (III) acetylacetonate n hydrate, lead (II) citrate trihydrate, cyclohexa Lead butyrate, calcium acetylacetonate dihydrate, chromium (III) acetylacetonate, gallium (III) trifluoromethanesulfonate, strontium dipivaloylmethanate, niobium pentachloride, molybdenylacetylacetonate, palladium ( II) Acetylacetonate, antimony (III) chloride, sodium tellurate, barium chloride dihydrate, tungsten chloride (VI) and the like.

  In the present invention, the concentration of the metal source in the metal oxide film forming solution is not particularly limited, but is, for example, in the range of 0.001 to 1 mol / l, particularly 0.01 to 0.5 mol. / L is preferable. This is because if the concentration is within the above range, the metal oxide film can be formed in a relatively short time.

  Next, a combination of metal sources used in the present invention will be described. As described above, in the present invention, two or more metal sources having different metal elements are used. The combination of the metal sources is not particularly limited as long as it is a combination of metal sources having different metal elements, and can be arbitrarily selected. This is because, when a metal source having a different metal element is used, when a metal oxide film is formed, crystals grow so as to repel each other and a porous metal oxide film can be formed.

  Among these, in the present invention, it is preferable to use two or more types of metal sources having a difference in lattice constant of 0.1 or more when the metal element of the metal source is a crystalline metal oxide. If there is a difference in lattice constant, two or more kinds of metal oxides maintain their crystal structures and repel each other, resulting in metal oxidation including a porous metal oxide having a small average pore size and a high surface area. This is because a material film can be obtained.

  In addition, the method for producing a metal oxide film of the present invention uses two or more types of metal sources having different metal elements. Among them, in the present invention, two or three types of metal sources having different metal elements are used. Is preferably used.

  In the present invention, a metal oxide film having a changed porosity is obtained by a combination of two or more kinds of metal sources used. As a combination of metal sources for changing the porosity, any combination can be adopted as described above. The combinations are exemplified below.

(I) Combination of copper-containing metal source and zinc-containing metal source In the present invention, it is preferable to combine a copper-containing metal source containing a copper element and a zinc-containing metal source containing a zinc element. In this case, a metal oxide film containing a porous component composed of copper oxide and zinc oxide can be obtained.

  The copper-containing metal source is not particularly limited as long as it contains a copper element, and may be a metal salt containing a copper element or an organometallic compound containing a copper element. Among them, an organometallic compound containing a copper element is preferable. Furthermore, examples of the organometallic source compound containing copper element include copper (II) acetylacetonate, copper (II) dipivaloylmethanate, and copper (II) ethylacetoacetate. (II) Acetylacetonate is preferred.

  The zinc-containing metal source is not particularly limited as long as it contains a zinc element, and may be a metal salt containing a zinc element or an organometallic compound containing a zinc element. Among them, an organometallic compound containing a zinc element is preferable. Furthermore, examples of the organic metal source compound containing zinc element include zinc acetylacetonate, zinc lactate trihydrate, zinc salicylate trihydrate, zinc stearate and the like, and particularly zinc acetylacetonate. Is preferred.

(Ii) Combination of nickel-containing metal source, zirconium-containing metal and yttrium-containing metal source In the present invention, the nickel-containing metal source containing nickel element, the zirconium-containing metal source containing zirconium element, and the yttrium element are contained. It is preferable to combine with an yttrium-containing metal source. In this case, a metal oxide film containing a porous component composed of nickel oxide and YSZ (yttria stabilized zirconia) can be obtained.

  The nickel-containing metal source is not particularly limited as long as it contains nickel element, and may be a metal salt containing nickel element or an organometallic compound containing nickel element. Among them, a metal salt containing nickel element is preferable. Furthermore, examples of the metal salt containing nickel element include nickel nitrate, nickel chloride, nickel sulfate, nickel perchlorate, nickel acetate, nickel phosphate, nickel bromate and the like. preferable.

  The zirconium-containing metal source is not particularly limited as long as it contains a zirconium element, and may be a metal salt containing a zirconium element or an organometallic compound containing a zirconium element. Among them, an organometallic compound containing a zirconium element is preferable. Furthermore, examples of the organometallic compound containing zirconium element include zirconium acetylacetonate, zirconium tetra-n-butoxide, zirconium (IV) ethoxide, zirconium normal propyrate, zirconium normal butyrate, zirconium tetraacetylacetonate, zirconium. Examples thereof include acetylacetonate bisethylacetoacetate, zirconium acetate, and zirconium monostearate, and zirconium acetylacetonate is particularly preferable.

  The yttrium-containing metal source is not particularly limited as long as it contains an yttrium element, and may be a metal salt containing an yttrium element or an organometallic compound containing an yttrium element. Among them, a metal salt containing an yttrium element is preferable. Furthermore, examples of the metal salt containing an yttrium element include yttrium nitrate, yttrium chloride, yttrium sulfate, yttrium perchlorate, yttrium acetate, yttrium phosphate, and yttrium bromate, and particularly yttrium nitrate. preferable.

  As described above, in the present invention, YSZ is preferably included as one component of the metal oxide film. The ratio of the zirconium-containing metal source and the yttrium-containing metal source used is not particularly limited as long as a desired YSZ can be obtained. For example, when the zirconium-containing metal source is 100, yttrium is converted in terms of mole. It is preferable that a containing metal source exists in the range of 5-20 in the range of 3-30 in.

(Iii) Combination of cobalt-containing metal source and iron-containing metal source In the present invention, it is preferable to combine a cobalt-containing metal source containing a cobalt element and an iron-containing metal source containing an iron element. In this case, a metal oxide film containing a porous component composed of cobalt oxide and iron oxide can be obtained.

  The cobalt-containing metal source is not particularly limited as long as it contains a cobalt element, and may be a metal salt containing a cobalt element or an organometallic compound containing a cobalt element. Among them, an organometallic compound containing a cobalt element is preferable. Furthermore, examples of the organometallic compound containing a cobalt element include cobalt acetylacetonate.

  The iron-containing metal source is not particularly limited as long as it contains an iron element, and may be a metal salt containing an iron element or an organometallic compound containing an iron element. Among them, a metal salt containing an iron element is preferable. Furthermore, examples of the metal salt containing an iron element include iron (III) nitrate, iron (II) sulfate, and iron (III) ammonium sulfate. Among these, iron (III) nitrate is preferable.

(Iv) Combination of titanium-containing metal source and lanthanum-containing metal source In the present invention, it is preferable to combine a titanium-containing metal source containing a titanium element and a lanthanum-containing metal source containing a lanthanum element. In this case, a metal oxide film containing a porous component composed of titanium oxide and lanthanum oxide can be obtained.

  The titanium-containing metal source is not particularly limited as long as it contains a titanium element, and may be a metal salt containing a titanium element or an organometallic compound containing a titanium element. Among them, an organometallic compound containing a titanium element is preferable. Furthermore, examples of the organometallic compound containing titanium element include titanium acetylacetonate, titanium lactate, tetraisopropyl titanate, tetranormal butyl titanate, tetra (2-ethylhexyl) titanate, butyl titanate dimer, titanium bis (ethylhexoxy) bis ( 2-ethyl-3-hydroxyhexoxide), diisopropoxytitanium bis (triethanolaminate), dihydroxybis (ammonium lactate) titanium, diisopropoxytitanium bis (ethylacetoacetate), titanium peroxocitrate ammonium tetrahydrate Among them, titanium acetylacetonate is preferable.

  The lanthanum-containing metal source is not particularly limited as long as it contains a lanthanum element, and may be a metal salt containing a lanthanum element or an organometallic compound containing a lanthanum element. Among them, a metal salt containing a lanthanum element is preferable. Furthermore, examples of the metal salt containing a lanthanum element include lanthanum chloride, lanthanum acetate, and lanthanum nitrate. Of these, lanthanum chloride is preferable.

(V) Combination of cerium-containing metal source and calcium-containing metal source In the present invention, it is preferable to combine a cerium-containing metal source containing a cerium element and a calcium-containing metal source containing a calcium element. In this case, a metal oxide film containing a porous component composed of cerium oxide and calcium oxide can be obtained.

  The cerium-containing metal source is not particularly limited as long as it contains a cerium element, and may be a metal salt containing a cerium element or an organometallic compound containing a cerium element. Among them, a metal salt containing a cerium element is preferable. Furthermore, examples of the metal salt containing a cerium element include cerium chloride, cerium acetate, cerium nitrate, cerium oxalate, diammonium cerium nitrate, and cerium sulfate. Among them, diammonium cerium nitrate is preferable.

  The calcium-containing metal source is not particularly limited as long as it contains calcium element, and may be a metal salt containing calcium element or an organometallic compound containing calcium element. Among them, a metal salt containing a calcium element is preferable. Furthermore, as a metal salt containing a calcium element, calcium chloride etc. can be mentioned, for example.

(Vi) Combination of indium-containing metal source and vanadium-containing metal source In the present invention, it is preferable to combine an indium-containing metal source containing an indium element and a vanadium-containing metal source containing a vanadium element. In this case, a metal oxide film containing a porous component made of indium oxide and vanadium oxide can be obtained.

  The indium-containing metal source is not particularly limited as long as it contains an indium element, and may be a metal salt containing an indium element or an organometallic compound containing an indium element. Among them, a metal salt containing an indium element is preferable. Furthermore, examples of the metal salt containing an indium element include indium chloride, indium nitrate, indium acetate, etc. Among them, indium chloride is preferable.

  The vanadium-containing metal source is not particularly limited as long as it contains a vanadium element, and may be a metal salt containing a vanadium element or an organometallic compound containing a vanadium element. Among them, a metal salt containing a vanadium element is preferable. Furthermore, examples of the metal salt containing the vanadium element include vanadium oxosulfate.

(Vii) Combination of tantalum-containing metal source and gadolinium-containing metal source In the present invention, it is preferable to combine a tantalum-containing metal source containing a tantalum element and a gadolinium-containing metal source containing a gadolinium element. In this case, a metal oxide film containing a porous component made of tantalum oxide and gadolinium oxide can be obtained.

  The tantalum-containing metal source is not particularly limited as long as it contains a tantalum element, and may be a metal salt containing a tantalum element or an organometallic compound containing a tantalum element. Among them, an organometallic compound containing a tantalum element is preferable. Furthermore, examples of the organometallic compound containing a tantalum element include tantalum (V) ethoxide, pentaisopropoxy tantalum, pentaethoxy tantalum, and the like. Among these, tantalum (V) ethoxide is preferable.

  The gadolinium-containing metal source is not particularly limited as long as it contains a gadolinium element, and may be a metal salt containing a gadolinium element or an organometallic compound containing a gadolinium element. Among them, a metal salt containing a gadolinium element is preferable. Furthermore, examples of the metal salt containing a gadolinium element include gadolinium nitrate.

(Viii) Combination of chromium-containing metal source and molybdenum-containing metal source In the present invention, it is preferable to combine a chromium-containing metal source containing a chromium element and a molybdenum-containing metal source containing a molybdenum element. In this case, a metal oxide film containing a porous component composed of chromium oxide and molybdenum oxide can be obtained.

  The chromium-containing metal source is not particularly limited as long as it contains a chromium element, and may be a metal salt containing a chromium element or an organometallic compound containing a chromium element. Among them, a metal salt containing a chromium element is preferable. Furthermore, examples of the metal salt containing chromium element include chromium chloride and ammonium chromate. Among them, chromium chloride is preferable.

  The molybdenum-containing metal source is not particularly limited as long as it contains a molybdenum element, and may be a metal salt containing a molybdenum element or an organometallic compound containing a molybdenum element. Among them, an organometallic compound containing a molybdenum element is preferable. Further, examples of the organometallic compound containing molybdenum element include ammonium molybdate phosphate and molybdenum sulfide, and among them, ammonium phosphate molybdate is preferable.

(Ix) Combination of tungsten-containing metal source and aluminum-containing metal source In the present invention, it is preferable to combine a tungsten-containing metal source containing a tungsten element and an aluminum-containing metal source containing an aluminum element. In this case, a metal oxide film containing a porous component made of tungsten oxide and aluminum oxide can be obtained.

  The tungsten-containing metal source is not particularly limited as long as it contains a tungsten element, and may be a metal salt containing a tungsten element or an organometallic compound containing a tungsten element. Among them, a metal salt containing a tungsten element is preferable. Furthermore, examples of the metal salt containing tungsten element include tungsten hexachloride, tungstic acid, ammonium tungstate, and the like. Among these, tungsten hexachloride is preferable.

  The aluminum-containing metal source is not particularly limited as long as it contains an aluminum element, and may be a metal salt containing an aluminum element or an organometallic compound containing an aluminum element. Among them, a metal salt containing an aluminum element is preferable. Furthermore, examples of the metal salt containing an aluminum element include aluminum nitrate and aluminum chloride. Among these, aluminum nitrate is preferable.

(2) Oxidizing agent Next, the oxidizing agent used in the present invention will be described. The metal oxide film forming solution used in the present invention may contain an oxidizing agent. By using the oxidant, the valence of metal ions and the like can be changed, and an environment in which a metal oxide film can be easily generated can be obtained, and a metal oxide film can be obtained at a lower substrate heating temperature. Can do.

  The concentration of the oxidant in the metal oxide film forming solution varies depending on the type of the oxidant, but is usually within a range of 0.001 to 1 mol / l, particularly 0.01 to 0.1 mol. / L is preferable. If the concentration is less than the above range, the effect of lowering the substrate heating temperature may not be sufficiently exhibited, if the concentration exceeds the above range, there is no significant difference in the effect obtained, This is because it is not preferable in terms of cost.

  Such an oxidizing agent is not particularly limited as long as it can be dissolved in a solvent described later and promote the oxidation of metal ions and the like. For example, hydrogen peroxide, sodium nitrite, Examples thereof include potassium nitrate, sodium bromate, potassium bromate, silver oxide, dichromic acid, and potassium permanganate. Among them, hydrogen peroxide and sodium nitrite are preferably used.

(3) Reducing agent Next, the reducing agent used for this invention is demonstrated. The metal oxide film forming solution used in the present invention may contain a reducing agent. By using the above reducing agent, the pH of the metal oxide film forming solution can be raised, leading to the metal oxide region or the metal hydroxide region in the Pourbaix diagram, and the metal oxide film is easily generated. The metal oxide film can be obtained at a lower substrate heating temperature.

  The concentration of the reducing agent in the metal oxide film forming solution varies depending on the type of the reducing agent, but is usually in the range of 0.001 to 1 mol / l, and more preferably 0.01 to 0.1 mol. / L is preferable. If the concentration is less than the above range, the effect of lowering the substrate heating temperature may not be sufficiently exhibited, if the concentration exceeds the above range, there is no significant difference in the effect obtained, This is because it is not preferable in terms of cost.

  Such a reducing agent is not particularly limited as long as it can be dissolved in a solvent described later and can release electrons by a decomposition reaction. For example, borane-tert-butylamine complex, borane- Examples thereof include borane complexes such as N, N diethylaniline complex, borane-dimethylamine complex, borane-trimethylamine complex, sodium cyanoborohydride, and sodium borohydride. Among these, borane complex is preferably used.

  Moreover, in this invention, you may use combining a reducing agent and the oxidizing agent mentioned above. Such a combination of a reducing agent and an oxidizing agent is not particularly limited as long as it is a combination capable of lowering the substrate heating temperature. For example, hydrogen peroxide or sodium nitrite and any reducing agent can be used. And a combination of an arbitrary oxidizing agent and a borane complex. Among them, a combination of hydrogen peroxide and a borane complex is preferable.

(4) Solvent Next, the solvent used in the present invention will be described. The solvent used in the present invention is not particularly limited as long as it can dissolve the above-described metal source and the like, for example, water; total carbon such as methanol, ethanol, isopropyl alcohol, propanol, butanol and the like. Lower alcohols having 5 or less; toluene; diketones such as acetylacetone, diacetyl, benzoylacetone; ketoesters such as ethyl acetoacetate, ethyl pyruvate, ethyl benzoylacetate, ethyl benzoylformate; and mixed solvents thereof Can do.

(5) Additive The metal oxide film forming solution used in the present invention may contain additives such as ceramic fine particles, an auxiliary ion source, and a surfactant.

By using the ceramic fine particles, a metal oxide film is formed so as to surround the ceramic fine particles, so that a mixed film of different ceramics can be obtained and the volume of the metal oxide film can be increased. In addition, it is preferable that the content of the ceramic fine particles is appropriately selected according to the characteristics of the member to be used.
Examples of the ceramic fine particles include ITO, aluminum oxide, zirconium oxide, silicon oxide, titanium oxide, tin oxide, cerium oxide, calcium oxide, manganese oxide, magnesium oxide, and barium titanate. Etc.

The auxiliary ion source reacts with electrons generated by thermal decomposition of the reducing agent and generates hydroxide ions. By using the above auxiliary ion source, the pH of the metal oxide film forming solution is raised and guided to the metal oxide region or the metal hydroxide region in the Pourbaix diagram, thereby creating an environment in which the metal oxide film is easily generated. A metal oxide film can be obtained at a lower substrate heating temperature. In addition, it is preferable to select and use the usage-amount of the said auxiliary ion source suitably according to the metal source and reducing agent to be used.
Examples of the ceramic fine particles include, for example, chlorate ions, perchlorate ions, chlorite ions, hypochlorite ions, bromate ions, hypobromate ions, nitrate ions, and nitrite ions. Mention may be made of the ionic species selected.

The surfactant acts on the interface between the metal oxide film forming solution and the substrate surface. By using the surfactant, the contact area between the metal oxide film forming solution and the substrate surface can be improved, and a uniform metal oxide film can be obtained. Particularly, when the metal oxide film forming solution is contacted by spraying, the droplets of the metal oxide film forming solution can be sufficiently brought into contact with the substrate surface due to the effect of the surfactant. Used for. In addition, it is preferable to select and use the usage-amount of the said surfactant suitably according to the metal source and reducing agent to be used.
Examples of the surfactant include Surfinol 485, Surfinol SE, Surfinol SE-F, Surfinol 504, Surfinol GA, Surfinol 104A, Surfinol 104BC, Surfinol 104PPM, Surfinol 104E, Surfinol. Examples include Surfinol series such as Nord 104PA (all manufactured by Nissin Chemical Industry Co., Ltd.), NIKKOL AM301, NIKKOL AM313ON (all manufactured by Nikko Chemical Co., Ltd.), and the like.

2. Next, the substrate used in the present invention will be described. The base material used in the present invention holds the metal oxide film.
The material of the base material is not particularly limited as long as it has sufficient heat resistance, and examples thereof include glass, SUS, metal plate, ceramic base material, heat resistant plastic, and the like. It is preferable to use glass, SUS, a metal plate, or a ceramic substrate. It is because it is excellent in versatility.
The base material may be, for example, one having a smooth surface, one having a fine structure, one having a hole, one having grooves, or one having a porous structure. Among them, those having a smooth surface are preferable.

3. Next, a method for bringing the metal oxide film forming solution into contact with a heated substrate while changing the metal source molar fraction will be described. In the present invention, the method for changing the metal source molar fraction is not particularly limited as long as a metal oxide film having changed porosity can be obtained. For example, as shown in FIG. A method using a plurality of metal oxide film forming solutions in which the metal source mole fraction is changed stepwise, and metal oxide film formation in which the metal source mole fraction is continuously changed as shown in FIG. And a method using a working solution.

  A metal oxide film whose porosity is changed stepwise can be obtained by a method using a plurality of metal oxide film forming solutions in which the metal source molar fraction is changed stepwise. Here, some specific examples of this method will be illustrated using the metal source A and the metal source B. Note that the metal source A and the metal source B have different metal elements.

  For example, using the apparatus shown in FIG. 1, first, a metal oxide film forming solution A containing only the metal source A is sprayed, and then a metal oxide film containing the metal source A and the metal source B When the forming solution (A + B) is sprayed, from the substrate surface side, a dense metal oxide layer derived from the metal source A, and a porous metal oxide layer derived from the metal source A and the metal source B, Can be obtained.

  Further, by using the apparatus shown in FIG. 1, first, a metal oxide film forming solution (A + B) containing a metal source A and a metal source B is sprayed, and then a metal oxidation containing only the metal source A is performed. When spraying the substance film forming solution A, from the substrate surface side, a porous metal oxide layer derived from the metal source A and the metal source B, a dense metal oxide layer derived from the metal source A, Can be obtained.

  Further, by using the apparatus shown in FIG. 1, first, a metal oxide film forming solution A containing only the metal source A is sprayed, and then a metal oxide film containing the metal source A and the metal source B. When the forming solution (A + B) is sprayed and then the metal oxide film forming solution A is sprayed again, a dense metal oxide layer derived from the metal source A and the metal source A and A metal oxide film comprising a porous metal oxide layer derived from the metal source B and a dense metal oxide layer derived from the metal source A can be obtained.

  On the other hand, a metal oxide film having a continuously variable porosity can be obtained by a method using the metal oxide film forming solution in which the metal source molar fraction is continuously changed. Here, some specific examples of this method are illustrated in the same manner as described above.

  For example, a metal oxide film-forming solution A containing only the metal source A and a metal oxide film-forming solution B containing only the metal source B are prepared, and the apparatus shown in FIG. In addition, when only the solution A is sprayed, and then sprayed by gradually increasing the flow rate of the solution B with respect to the solution A, the substrate surface side is dense, and the porosity continuously increases toward the opposite side. An oxide film can be obtained.

  Also, a metal oxide film-forming solution A containing only the metal source A and a metal oxide film-forming solution B containing only the metal source B were prepared, and first using the apparatus shown in FIG. When the mixed solution of the solution A and the solution B is sprayed, and then sprayed by gradually decreasing the flow rate of the solution B with respect to the solution A, the substrate surface side is dense and the porosity is increased toward the opposite side. A metal oxide film that continuously increases can be obtained.

  Also, a metal oxide film-forming solution A containing only the metal source A and a metal oxide film-forming solution B containing only the metal source B were prepared, and first using the apparatus shown in FIG. In the case of spraying only the solution A, and then spraying by gradually increasing the flow rate of the solution B with respect to the solution A, and then spraying by gradually decreasing the flow rate of the solution B with respect to the solution A, It is possible to obtain a metal oxide film that is dense on the side and once increases in porosity toward the opposite side and then decreases in porosity again.

4). Next, a contact method between the substrate and the metal oxide film forming solution in the present invention will be described. The contact method is not particularly limited as long as it is a method in which the above-described base material and the above-described metal oxide film forming solution are brought into contact with each other, but the metal oxide film-forming solution and the base material are brought into contact with each other. It is preferable that the method does not lower the temperature of the substrate. This is because if the temperature of the substrate is lowered, the film formation reaction does not occur and a desired metal oxide film may not be obtained. As a method for preventing the temperature of the base material from being lowered, for example, a method of bringing the metal oxide film forming solution into contact with the base material as droplets, and the like are preferable. If the diameter of the droplet is small, the solvent of the metal oxide film forming solution is instantly evaporated, and the decrease in the substrate temperature can be further suppressed. Further, since the droplet diameter is small, a uniform film can be obtained. This is because a thick metal oxide film can be obtained.

  The method for bringing the droplet of the metal oxide film forming solution having such a small diameter into contact with the substrate is not particularly limited. Specifically, the metal oxide film forming solution is sprayed. The method of making it contact with a base material by this, the method of passing a base material in the space which made the metal oxide film formation solution mist-like, etc. are mentioned.

  Examples of the method of bringing the metal oxide film forming solution into contact with the substrate by spraying include a spraying method using a spray device or the like. In the case of spraying using the above spray device or the like, the diameter of the droplets is preferably within a range of 0.1 to 1000 μm, and more preferably within a range of 0.5 to 300 μm. This is because if the droplet diameter is within the above range, the substrate temperature can be prevented from decreasing, and a uniform metal oxide film can be obtained.

  The spray gas of the spray device is not particularly limited as long as it does not inhibit the formation of the metal oxide film, and examples thereof include air, nitrogen, argon, helium, oxygen and the like. Active gases such as nitrogen, argon and helium are preferred. In addition, the injection amount of the injection gas is, for example, preferably in the range of 0.1 to 50 l / min, and more preferably in the range of 1 to 20 l / min. The spray device may be a fixed device, a movable device, a device that ejects the solution by rotation, a device that ejects only the solution by pressure, or the like. As such a spray device, a commonly used spray device can be used, for example, hand spray (spray gun No. 8012, manufactured by ASONE), ultrasonic nepriser (NE-U17, manufactured by OMRON), etc. Can be used.

  Moreover, in the method of allowing the substrate to pass through the space in which the metal oxide film forming solution is made into a mist, the diameter of the droplets is usually within the range of 0.1 to 300 μm, particularly within the range of 1 to 100 μm. It is preferable that This is because if the droplet diameter is within the above range, the substrate temperature can be prevented from decreasing, and a uniform metal oxide film can be obtained.

  In the present invention, the metal oxide film forming solution and the heated substrate are brought into contact with each other. At this time, the substrate is heated to a temperature equal to or higher than the above-described “metal oxide film forming temperature”. Such “metal oxide film formation temperature” varies depending on the type of metal source such as a metal salt and an organometallic compound, and the composition of the metal oxide film forming solution such as a solvent. It is preferably in the range of 600 ° C, and more preferably in the range of 250 to 400 ° C.

  In addition, the heating method for the base material is not particularly limited, and examples thereof include a heating method such as a hot plate, an oven, a firing furnace, an infrared lamp, a hot air blower, etc. A method in which the metal oxide film forming solution can be contacted while maintaining the temperature at the above temperature is preferable, and specifically, a hot plate or the like is preferably used.

  Next, the contact method between the substrate and the metal oxide film forming solution in the present invention will be specifically described with reference to the drawings. Examples of the method of bringing the metal oxide film forming solution into contact with the substrate by spraying the above-described method include, for example, a method of continuously moving and spraying the substrate with a roller, a method of spraying on a fixed substrate, The method etc. which spray on the flow path like a pipe are mentioned.

  As a method for continuously moving and spraying the substrate with the roller, for example, as shown in FIG. 3, a metal oxide containing only the metal source A using a metal source A and a metal source B having different metal elements is used. A film forming solution A and a metal oxide film forming solution B containing only the metal source B are prepared, and the substrate 1 is heated to a temperature equal to or higher than the metal oxide film forming temperature using rollers 3 to 6. The metal oxide film is formed by spraying only the solution A at first using the spray device 2 and then spraying while gradually increasing the flow rate of the solution B with respect to the solution A. Methods and the like. By this method, it is possible to obtain a metal oxide film whose porosity is changed in a direction perpendicular to the stacking direction of the metal oxide film (moving direction of the base material).

  Moreover, the method of spraying on the fixed base material, for example, as shown in FIG. 1 or FIG. 2, heats the base material 1 to a temperature equal to or higher than the metal oxide film formation temperature using a hot plate or the like, Examples thereof include a method of forming a metal oxide film by spraying the metal oxide film forming solution using the spray device 2. By this method, it is possible to obtain a metal oxide film whose porosity is changed in the stacking direction of the metal oxide films.

  In addition, as a method of passing the base material through the space in which the above-described solution for forming a metal oxide film is made into a mist, for example, as shown in FIG. The metal oxide film is heated to a temperature equal to or higher than the material film formation temperature, and the metal oxide film forming solution A containing only the metal source A is passed through the mist-like space, and then the metal containing the metal source A and metal source B For example, a method of forming a metal oxide film by passing the oxide film forming solution (A + B) through a mist-like space may be used. By this method, a metal oxide film whose porosity has changed in the stacking direction of the metal oxide film can be obtained.

5. In addition, in the method for producing a metal oxide film of the present invention, the metal oxide film obtained by the above-described contact method or the like may be washed. The cleaning of the metal oxide film is performed to remove impurities present on the surface of the metal oxide film, for example, a method of cleaning using a solvent used in the metal oxide film forming solution. Etc.

B. Laminated body Next, the laminated body of this invention is demonstrated. The laminate of the present invention is a laminate having a base material and a metal oxide film formed on the base material, wherein the metal oxide film has two or more kinds of metal oxides having different metal elements. And the porosity of the metal oxide film is continuously changing.

  According to this invention, since it has a metal oxide film | membrane whose porosity changed continuously, it can be set as the laminated body applicable to various uses.

Next, the laminated body of this invention is demonstrated using drawing. FIG. 5 is a schematic cross-sectional view showing an example of the laminate of the present invention. The laminate shown in FIG. 5 has a substrate 1 and a metal oxide film 6 formed on the substrate 1, and the porosity of the metal oxide film 6 is the lowest on the substrate surface side. As it goes to the surface side opposite to the material surface side, it continuously increases in the stacking direction.
Hereinafter, the laminated body of this invention is demonstrated for every structure.

1. Metal Oxide Film First, the metal oxide film used in the present invention will be described. The metal oxide film used in the present invention is formed on a substrate to be described later, has two or more different metal elements, and its porosity is continuously changing. In general, the metal oxide film is obtained by the method described in “A. Method for producing metal oxide film” described above.

  In the present invention, the direction in which the porosity of the metal oxide film continuously changes is not particularly limited, and examples thereof include a laminating direction and a direction orthogonal to the laminating direction. Direction is preferred. That is, in the present invention, it is preferable that the porosity of the metal oxide film is continuously changed in the stacking direction. This is because a laminate having excellent versatility can be obtained. Specific examples of such a metal oxide film include those described in “A. Method for producing metal oxide film 3. Method for changing metal source molar fraction” described above.

  Further, in the present invention, the porosity of the metal oxide film continuously changes because the cross section (stacking direction) of the metal oxide film is measured by a transmission electron microscope (TEM) or a scanning electron microscope (SEM). ). Or it can confirm by investigating the ratio of the metal element which exists in a metal oxide film, etc. with a photoelectron spectrometer (ESCA).

  The film thickness of the metal oxide film varies depending on the use of the laminate of the present invention, and is not particularly limited. For example, the film thickness is in the range of 10 nm to 50 μm, and particularly in the range of 100 nm to 10 μm. Preferably there is.

2. Next, the substrate used in the present invention will be described. The base material used in the present invention holds the metal oxide film. The type of the base material is the same as that described in “A. Metal oxide film manufacturing method 2. Base material” described above, and thus the description thereof is omitted here. Further, the thickness and size of the substrate are not particularly limited, and it is preferable to select appropriately according to the use of the present invention.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

  Hereinafter, the present invention will be specifically described with reference to examples.

[Reference Example 1]
In this reference example, a porous metal oxide film made of copper oxide and zinc oxide was produced.
First, a glass plate (75 mm × 25 mm, thickness 0.7 mm) was prepared as a substrate.
Next, a solvent (ethanol 15% by weight, toluene) so that copper acetylacetonate (manufactured by Kanto Chemical Co., Inc.) has a concentration of 0.02 mol / l and zinc acetylacetonate (manufactured by Kanto Chemical Co., Ltd.) has a concentration of 0.02 mol / l. 85 ml) to prepare 500 ml of a porous metal oxide film forming solution.

  Next, the substrate (glass plate) is heated to 500 ° C. with a hot plate (manufactured by ASONE), and the porous metal oxide film forming solution is applied to the substrate with an ultrasonic neplyzer (manufactured by OMRON). 500 ml was sprayed to obtain a porous metal oxide film on the substrate.

  When the porous metal oxide film obtained by the above method was observed with a scanning electron microscope (SEM), it was a porous metal oxide film composed of fine particles having an average particle diameter of 15 nm, and the film thickness was 400 nm. . From the image analysis results, the average pore diameter of the porous metal oxide film was 10 nm. An SEM photograph of the obtained porous metal oxide film is shown in FIG. FIG. 6 is a plan view of the obtained porous metal oxide film. Furthermore, it was clarified that it was composed of copper oxide and zinc oxide by measurement with an X-ray diffractometer (XRD) and a photoelectron spectrometer (ESGLAB200I-XL, manufactured by VG Scientific).

[Example 1-1]
In this example, a metal oxide film whose porosity was changed stepwise in the stacking direction was produced.
First, a glass plate (75 mm × 25 mm, thickness 0.7 mm) was prepared as a substrate.
Next, copper acetylacetonate (manufactured by Kanto Chemical Co., Inc.) was dissolved in a solvent (ethanol 15%, toluene 85%) to a concentration of 0.02 mol / l to prepare 500 ml of a metal oxide film forming solution A. . Next, a solvent (ethanol 15% by weight, toluene) so that copper acetylacetonate (manufactured by Kanto Chemical Co., Inc.) has a concentration of 0.02 mol / l and zinc acetylacetonate (manufactured by Kanto Chemical Co., Ltd.) has a concentration of 0.02 mol / l. 85 ml) to prepare 500 ml of metal oxide film forming solution B.

  Next, the base material (glass plate) is heated to 500 ° C. with a hot plate (manufactured by ASONE Co., Ltd.), and the metal oxide film forming solutions A and B are sequentially applied to the base material by an ultrasonic nebulizer ( All of them were sprayed with Omron Corporation to obtain a metal oxide film on the substrate.

  When the cross section of the metal oxide film obtained by the above method was observed using a scanning electron microscope (SEM), a dense copper oxide film derived from copper acetylacetonate, and copper acetyl in order from the base material. It was confirmed that a porous metal oxide film derived from acetonate and zinc acetylacetonate was formed (see FIG. 7).

[Example 1-2]
In this example, a metal oxide film whose porosity was continuously changed in the stacking direction was produced.
First, the glass plate similar to Example 1-1 was prepared as a base material.
Next, the base material (glass plate) was heated to 500 ° C. with a hot plate (manufactured by ASONE), and the metal oxide film forming solution A used in Example 1-1 was ultrasonically applied to the base material. When spraying 150 ml with a nepriser (manufactured by OMRON Corporation), the metal oxide film forming solution used in Example 1-1 was used at a rate of 1 ml per 30 seconds with respect to the container containing the metal oxide film forming solution A. Solution B was added to obtain a metal oxide film on the substrate.

  When the cross section of the metal oxide film obtained by the above method was observed using a scanning electron microscope (SEM), it was confirmed that the porosity continuously changed from the base material (see FIG. 8). ).

[Reference Example 2]
In this reference example, a porous metal oxide film made of nickel oxide and YSZ (yttria stabilized zirconia) was produced.
First, a cerium oxide substrate doped with 30% gadolinium was prepared as a substrate.
Next, zirconium acetylacetonate (manufactured by Kanto Chemical Co., Inc.) has a concentration of 0.1 mol / l, yttrium nitrate (manufactured by Kanto Chemical Co., Ltd.) has a concentration of 0.008 mol / l, and nickel nitrate (manufactured by Kanto Chemical Co., Ltd.) has a concentration of 0.1 mol / l. / L was dissolved in a solvent (ethanol 50% by weight, toluene 50% by weight) to prepare 300 ml of a porous metal oxide film forming solution.

  Next, the substrate is heated to 500 ° C. with a hot plate (manufactured by ASONE), and 300 ml of the porous metal oxide film forming solution is sprayed onto the substrate with an ultrasonic nebulizer (manufactured by OMRON). As a result, a porous metal oxide film was obtained on the substrate.

  When the porous metal oxide film obtained by the above method was observed with a scanning electron microscope (SEM), it was a porous metal oxide film composed of fine particles having an average particle diameter of 100 nm, and the film thickness was 200 nm. . From the image analysis results, the average pore size of the porous metal oxide film was 60 nm. An SEM photograph of the obtained porous metal oxide film is shown in FIG. FIG. 9A is a plan view of the obtained porous metal oxide film, and FIG. 9B is a cross-sectional view of the obtained porous metal oxide film. Furthermore, it was clarified that it is composed of nickel oxide and YSZ by measurement with an X-ray diffractometer (XRD) and a photoelectron spectrometer (ESGLAB200I-XL, manufactured by VG Scientific).

[Example 2]
In this example, a metal oxide film made of nickel oxide and YSZ (yttria-stabilized zirconia) and having a porosity continuously changing in the stacking direction was produced.
First, a cerium oxide substrate doped with 30% gadolinium was prepared as a substrate.
Next, a solvent (50% by weight of ethanol, 50% by weight of toluene) so that zirconium acetylacetonate (manufactured by Kanto Chemical Co., Inc.) has a concentration of 0.1 mol / l and yttrium nitrate (manufactured by Kanto Chemical Co., Ltd.) has a concentration of 0.008 mol / l. %) To prepare 1 L of metal oxide film forming solution A. On the other hand, nickel nitrate (manufactured by Kanto Chemical Co., Inc.) was dissolved in a solvent (ethanol 80 wt%, water 20 wt%) so that the concentration was 0.1 mol / l to prepare 1 L of metal oxide film forming solution B.

  Next, the substrate is heated to 500 ° C. with a hot plate (manufactured by ASONE), and 150 ml of the metal oxide film forming solution A is sprayed onto the substrate with an ultrasonic nebulizer (manufactured by OMRON). The metal oxide film forming solution B was added to the container containing the metal oxide film forming solution A at a rate of 1 ml per 30 seconds to obtain a metal oxide film on the substrate.

  When the cross section of the metal oxide film obtained by the above method was observed using a scanning electron microscope (SEM), it was confirmed that the porosity continuously changed from the base material (see FIG. 10). ).

[Reference Example 3]
In this reference example, a porous metal oxide film made of cobalt oxide and iron oxide was produced.
First, a glass plate (75 mm × 25 mm, thickness 0.7 mm) was prepared as a substrate.
Next, a solvent (ethanol) is used so that cobalt acetylacetonate (manufactured by Kanto Chemical Co., Inc.) has a concentration of 0.1 mol / l and iron nitrate (III) nonahydrate (manufactured by Kanto Chemical Co., Ltd.) has a concentration of 0.1 mol / l. 100 ml of a solution for forming a porous metal oxide film was prepared.

  Next, the substrate (glass plate) is heated to 500 ° C. with a hot plate (manufactured by ASONE), and the porous metal oxide film forming solution is applied to the substrate with an ultrasonic neplyzer (manufactured by OMRON). 100 ml was sprayed to obtain a porous metal oxide film on the substrate.

  When the porous metal oxide film obtained by the above method was observed with a scanning electron microscope (SEM), it was a porous metal oxide film composed of fine particles having an average particle diameter of 60 nm, and the film thickness was 200 nm. . From the image analysis results, the average pore diameter of the porous metal oxide film was 30 nm. An SEM photograph of the obtained porous metal oxide film is shown in FIG. FIG. 11 is a plan view of the obtained porous metal oxide film. Furthermore, it was clarified that it was composed of cobalt oxide and iron oxide by measurement with an X-ray diffractometer (XRD) and a photoelectron spectrometer (ESGLAB200I-XL, manufactured by VG Scientific).

[Example 3]
In this example, a metal oxide film whose porosity was continuously changed in the stacking direction was produced.
First, a glass plate (75 mm × 25 mm, thickness 0.7 mm) was prepared as a substrate.
Next, cobalt acetylacetonate (manufactured by Kanto Chemical Co., Inc.) was dissolved in a solvent (ethanol 50%, toluene 50%) to a concentration of 0.1 mol / l to prepare 100 ml of metal oxide film forming solution A. . Next, iron nitrate (III) nonahydrate (manufactured by Kanto Chemical Co., Inc.) was dissolved in a solvent (ethanol) to a concentration of 0.1 mol / l to prepare 100 ml of metal oxide film forming solution B.

Next, the base material (glass plate) is heated to 500 ° C. with a hot plate (manufactured by ASONE), and the metal oxide film forming solution A is applied to the base material with an ultrasonic nebulizer (manufactured by OMRON). When spraying 100 ml, the metal oxide film forming solution B is added to the container containing the metal oxide film forming solution A at a rate of 1 ml per 30 seconds to obtain a metal oxide film on the substrate. It was.
When the cross section of the metal oxide film obtained by the above method was observed using a scanning electron microscope (SEM), it was confirmed that the porosity continuously changed from the base material (see FIG. 12). ).

[Reference Example 4]
In this reference example, a porous metal oxide film made of titanium oxide and lanthanum oxide was produced.
First, a glass plate (75 mm × 25 mm, thickness 0.7 mm) was prepared as a substrate.
Next, a solvent (50% by weight of ethanol) was used so that titanium acetylacetonate (manufactured by Kanto Chemical Co., Inc.) had a concentration of 0.1 mol / l and lanthanum chloride heptahydrate (manufactured by Kanto Chemical Co., Ltd.) had a concentration of 0.1 mol / l. And 100 ml of a solution for forming a porous metal oxide film was prepared.

  Next, the substrate (glass plate) is heated to 500 ° C. with a hot plate (manufactured by ASONE), and the porous metal oxide film forming solution is applied to the substrate with an ultrasonic neplyzer (manufactured by OMRON). 100 ml was sprayed to obtain a porous metal oxide film on the substrate.

  When the porous metal oxide film obtained by the above method was observed with a scanning electron microscope (SEM), it was a porous metal oxide film composed of fine particles having an average particle diameter of 30 nm, and the film thickness was 300 nm. . From the image analysis results, the average pore diameter of the porous metal oxide film was 20 nm. An SEM photograph of the obtained porous metal oxide film is shown in FIG. FIG. 13 is a plan view of the obtained porous metal oxide film. Furthermore, it was clarified that it was composed of titanium oxide and lanthanum oxide by measurement with an X-ray diffractometer (XRD) and a photoelectron spectrometer (ESGLAB 200I-XL, manufactured by VG Scientific).

[Example 4]
In this example, a metal oxide film whose porosity was changed stepwise in the stacking direction was produced.
First, a glass plate (75 mm × 25 mm, thickness 0.7 mm) was prepared as a substrate.
Next, titanium acetylacetonate (manufactured by Kanto Chemical Co., Inc.) is dissolved in a solvent (ethanol 50% by weight, isopropyl alcohol 50% by weight) to a concentration of 0.1 mol / l, and a metal oxide film forming solution A is obtained. 200 ml was prepared. Next, titanium acetylacetonate (manufactured by Kanto Chemical Co., Inc.) is dissolved in a solvent (ethanol) so that the concentration is 0.05 mol / l and lanthanum chloride heptahydrate (manufactured by Kanto Chemical Co., Ltd.) is 0.05 mol / l. 100 ml of metal oxide film forming solution B was prepared.

  Next, the base material (glass plate) is heated to 500 ° C. with a hot plate (manufactured by ASONE Co., Ltd.), and the metal oxide film forming solutions A and B are sequentially applied to the base material by an ultrasonic nebulizer ( All of them were sprayed with Omron Corporation to obtain a metal oxide film on the substrate.

  When the cross section of the metal oxide film obtained by the above method was observed using a scanning electron microscope (SEM), a dense titanium oxide film derived from titanium acetylacetonate, and titanium acetyl, in order from the base material. It was confirmed that a porous metal oxide film derived from acetonate and lanthanum chloride was formed (see FIG. 14).

[Reference Example 5]
In this reference example, a porous metal oxide film made of cerium oxide and calcium oxide was produced.
First, a glass plate (75 mm × 25 mm, thickness 0.7 mm) was prepared as a substrate.
Next, a solvent (ethanol 50% by weight, ethanol diammonium cerium (IV) (manufactured by Kanto Chemical Co., Inc.) was adjusted to a concentration of 0.1 mol / l and calcium chloride (manufactured by Kanto Chemical Co., Ltd.) to a concentration of 0.1 mol / l. 300 ml of an ethyl acetoacetate solution was prepared to prepare 300 ml of a porous metal oxide film forming solution.

  Next, the substrate (glass plate) is heated to 500 ° C. with a hot plate (manufactured by ASONE), and the porous metal oxide film forming solution is applied to the substrate with an ultrasonic neplyzer (manufactured by OMRON). 300 ml was sprayed to obtain a porous metal oxide film on the substrate.

  When the porous metal oxide film obtained by the above method was observed with a scanning electron microscope (SEM), the film thickness was 350 nm. From the image analysis results, the average pore size of the porous metal oxide film was 100 nm. An SEM photograph of the obtained porous metal oxide film is shown in FIG. FIG. 15 is a plan view of the obtained porous metal oxide film. Furthermore, it was clarified that it was composed of cerium oxide and calcium oxide by measurement with an X-ray diffractometer (XRD) and a photoelectron spectrometer (ESGLAB 200I-XL, manufactured by VG Scientific).

[Example 5]
In this example, a metal oxide film whose porosity was continuously changed in the stacking direction was produced.
First, a porous substrate (φ13 mm, thickness 0.8 mm) composed of nickel oxide and samarium-doped ceria cermet was prepared as a base material.
Next, diammonium cerium (IV) nitrate (manufactured by Kanto Chemical Co., Inc.) is dissolved in a solvent (ethanol 50 wt%, ethyl acetoacetate 50 wt%) to a concentration of 0.1 mol / l to form a metal oxide film 500 ml of preparation solution A was prepared. Next, calcium chloride (manufactured by Kanto Chemical Co., Inc.) is dissolved in a solvent (ethanol 50 wt%, ethyl acetoacetate 50 wt%) to a concentration of 0.1 mol / l, and 500 ml of metal oxide film forming solution B is added. Prepared.

  Next, the base material (porous substrate) is heated to 500 ° C. with a hot plate (manufactured by ASONE), and the metal oxide film forming solution A is applied to the ultrasonic nebulizer (manufactured by OMRON Corporation). When spraying 500 ml, the metal oxide film forming solution B is added at a rate of 2 ml per 30 seconds to the container containing the metal oxide film forming solution A, and the metal oxide film is formed on the substrate. Obtained.

  When the cross section of the metal oxide film obtained by the above method was observed using a scanning electron microscope (SEM), a dense film was first formed from the porous substrate, and the porosity continuously changed thereafter. It was confirmed that this was done (see FIG. 16).

[Reference Example 6]
In this reference example, a porous metal oxide film made of indium oxide and vanadium oxide was produced.
First, a glass plate (75 mm × 25 mm, thickness 0.7 mm) was prepared as a substrate.
Next, a solvent (ethanol 50 wt%, acetone 50 wt%) so that indium chloride (Kanto Chemical Co., Ltd.) has a concentration of 0.05 mol / l and vanadium oxosulfate (Kanto Chemical Co., Ltd.) has a concentration of 0.12 mol / l. 100 ml of a solution for forming a porous metal oxide film was prepared.

  Next, the substrate (glass plate) is heated to 500 ° C. with a hot plate (manufactured by ASONE), and the porous metal oxide film forming solution is applied to the substrate with an ultrasonic neplyzer (manufactured by OMRON). 100 ml was sprayed to obtain a porous metal oxide film on the substrate.

  When the porous metal oxide film obtained by the above method was observed with a scanning electron microscope (SEM), it was a porous metal oxide film composed of fine particles having an average particle diameter of 150 nm, and the film thickness was 350 nm. . From the image analysis results, the average pore size of the porous metal oxide film was 60 nm. An SEM photograph of the obtained porous metal oxide film is shown in FIG. FIG. 17 is a plan view of the obtained porous metal oxide film. Furthermore, it was clarified that it was composed of indium oxide and vanadium oxide by measurement using an X-ray diffractometer (XRD) and a photoelectron spectrometer (ESGLAB 200I-XL, manufactured by VG Scientific).

[Reference Example 7]
In this reference example, a porous metal oxide film made of tantalum oxide and gadolinium oxide was produced.
First, a glass plate (75 mm × 25 mm, thickness 0.7 mm) was prepared as a substrate.
Next, a solvent (ethanol 50% by weight, acetylacetone 50) so that tantalum (V) ethoxide (manufactured by Kanto Chemical Co., Inc.) has a concentration of 0.1 mol / l and gadolinium nitrate (manufactured by Kanto Chemical Co., Ltd.) has a concentration of 0.15 mol / l. 100 ml of a solution for forming a porous metal oxide film was prepared.

  Next, the substrate (glass plate) is heated to 500 ° C. with a hot plate (manufactured by ASONE), and the porous metal oxide film forming solution is applied to the substrate with an ultrasonic neplyzer (manufactured by OMRON). 100 ml was sprayed to obtain a porous metal oxide film on the substrate.

  When the porous metal oxide film obtained by the above method was observed with a scanning electron microscope (SEM), it was a porous metal oxide film composed of fine particles having an average particle diameter of 20 nm, and the film thickness was about 600 nm. It was. An SEM photograph of the obtained porous metal oxide film is shown in FIG. FIG. 18 is a cross-sectional view of the obtained porous metal oxide film. Furthermore, it was clarified that it was composed of tantalum oxide and gadolinium oxide by measurement with an X-ray diffractometer (XRD) and a photoelectron spectroscopic analyzer (manufactured by VG Scientific, ESCALAB 200I-XL).

[Reference Example 8]
In this reference example, a porous metal oxide film made of chromium oxide and molybdenum oxide was produced.
First, a glass plate (75 mm × 25 mm, thickness 0.7 mm) was prepared as a substrate.
Next, a solvent (ethanol 50% by weight, acetoacetic acid) was prepared so that chromium chloride (manufactured by Kanto Chemical Co., Inc.) had a concentration of 0.1 mol / l and ammonium phosphate molybdate (manufactured by Kanto Chemical Co., Ltd.) had a concentration of 0.1 mol / l. 100 ml of a solution for forming a porous metal oxide film was prepared.

  Next, the substrate (glass plate) is heated to 500 ° C. with a hot plate (manufactured by ASONE), and the porous metal oxide film forming solution is applied to the substrate with an ultrasonic neplyzer (manufactured by OMRON). 100 ml was sprayed to obtain a porous metal oxide film on the substrate.

  When the porous metal oxide film obtained by the above method was observed with a scanning electron microscope (SEM), it was a porous metal oxide film composed of fine particles having an average particle diameter of 20 nm, and the film thickness was 100 nm. . From the image analysis results, the average pore size of the porous metal oxide film was 15 nm. An SEM photograph of the obtained porous metal oxide film is shown in FIG. FIG. 19 is a plan view of the obtained porous metal oxide film. Furthermore, it was revealed by the X-ray diffractometer (XRD) and the photoelectron spectroscopic analyzer (VG Scientific, ESCALAB200I-XL) that it is composed of chromium oxide and molybdenum oxide.

[Reference Example 9]
In this reference example, a porous metal oxide film made of tungsten oxide and aluminum oxide was produced.
First, a glass plate (75 mm × 25 mm, thickness 0.7 mm) was prepared as a substrate.
Next, a solvent (50% by weight of ethanol, 50% by weight of acetylacetone) so that tungsten hexachloride (manufactured by Kanto Chemical Co., Inc.) has a concentration of 0.2 mol / l and aluminum nitrate (manufactured by Kanto Chemical Co., Ltd.) has a concentration of 0.2 mol / l. 500 ml of a solution for forming a porous metal oxide film was prepared.

  Next, the substrate (glass plate) is heated to 500 ° C. with a hot plate (manufactured by ASONE), and the porous metal oxide film forming solution is applied to the substrate with an ultrasonic neplyzer (manufactured by OMRON). 500 ml was sprayed to obtain a porous metal oxide film on the substrate.

  When the porous metal oxide film obtained by the above method was observed with a scanning electron microscope (SEM), it was a porous metal oxide film composed of fine particles having an average particle diameter of 20 nm, and the film thickness was 400 nm. . From the image analysis results, the average pore size of the porous metal oxide film was 60 nm. An SEM photograph of the obtained porous metal oxide film is shown in FIG. FIG. 20 is a plan view of the obtained porous metal oxide film. Furthermore, it was clarified that it was composed of tungsten oxide and aluminum oxide by measurement with an X-ray diffractometer (XRD) and a photoelectron spectrometer (ESGLAB200I-XL, manufactured by VG Scientific).

It is explanatory drawing which shows an example of the manufacturing method of the metal oxide film of this invention. It is explanatory drawing which shows the other example of the manufacturing method of the metal oxide film of this invention. It is explanatory drawing which shows the other example of the manufacturing method of the metal oxide film of this invention. It is explanatory drawing which shows the other example of the manufacturing method of the metal oxide film of this invention. It is a schematic sectional drawing which shows an example of the laminated body of this invention. 4 is a SEM photograph of the metal oxide film obtained in Reference Example 1. It is a SEM photograph of the metal oxide film obtained in Example 1-1. It is a SEM photograph of the metal oxide film obtained in Example 1-2. 4 is a SEM photograph of the metal oxide film obtained in Reference Example 2. 3 is a SEM photograph of the metal oxide film obtained in Example 2. 4 is a SEM photograph of the metal oxide film obtained in Reference Example 3. 4 is a SEM photograph of the metal oxide film obtained in Example 3. 4 is a SEM photograph of the metal oxide film obtained in Reference Example 4. 4 is a SEM photograph of the metal oxide film obtained in Example 4. 6 is a SEM photograph of the metal oxide film obtained in Reference Example 5. 6 is a SEM photograph of the metal oxide film obtained in Example 5. 10 is a SEM photograph of the metal oxide film obtained in Reference Example 6. 10 is a SEM photograph of the metal oxide film obtained in Reference Example 7. 10 is a SEM photograph of the metal oxide film obtained in Reference Example 8. 10 is a SEM photograph of the metal oxide film obtained in Reference Example 9.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Base material 2 ... Spray apparatus 3, 4, 5 ... Roller 6 ... Metal oxide film

Claims (12)

Using two or more types of metal sources having different metal elements, a metal oxide film forming solution having different metal source molar fractions of the two or more types of metal sources while changing the metal source molar fraction while performing metal oxidation A method for producing a metal oxide film, wherein a metal oxide film having a changed porosity is formed on the substrate by bringing the substrate into contact with a substrate heated to a temperature equal to or higher than a physical film formation temperature ,
The method of bringing the metal oxide film forming solution into contact with the base material is a method of bringing the metal oxide film forming solution into contact with the base material by spraying the metal oxide film forming solution, or the metal oxide film forming solution. A method for producing a metal oxide film, characterized in that the substrate is passed through a mist-like space .   The method for producing a metal oxide film according to claim 1, wherein the metal source is a metal salt or an organometallic compound.   2. The metal oxide film according to claim 1, wherein the metal oxide film forming solution has a copper-containing metal source containing a copper element and a zinc-containing metal source containing a zinc element. Production method.   The metal oxide film forming solution has a nickel-containing metal source containing a nickel element, a zirconium-containing metal source containing a zirconium element, and an yttrium-containing metal source containing an yttrium element. The method for producing a metal oxide film according to claim 1.   2. The metal oxide film according to claim 1, wherein the metal oxide film forming solution has a cobalt-containing metal source containing a cobalt element and an iron-containing metal source containing an iron element. Production method.   2. The metal oxide film according to claim 1, wherein the metal oxide film forming solution has a titanium-containing metal source containing a titanium element and a lanthanum-containing metal source containing a lanthanum element. Production method.   2. The metal oxide film according to claim 1, wherein the metal oxide film forming solution includes a cerium-containing metal source containing a cerium element and a calcium-containing metal source containing a calcium element. Production method.   2. The metal oxide film according to claim 1, wherein the metal oxide film forming solution has an indium-containing metal source containing an indium element and a vanadium-containing metal source containing a vanadium element. Production method.   2. The metal oxide film according to claim 1, wherein the metal oxide film forming solution has a tantalum-containing metal source containing a tantalum element and a gadolinium-containing metal source containing a gadolinium element. Production method.   2. The metal oxide film according to claim 1, wherein the metal oxide film forming solution has a chromium-containing metal source containing a chromium element and a molybdenum-containing metal source containing a molybdenum element. Production method.   2. The metal oxide film according to claim 1, wherein the metal oxide film forming solution has a tungsten-containing metal source containing a tungsten element and an aluminum-containing metal source containing an aluminum element. Production method. A laminate having a substrate and a metal oxide film formed on the substrate,
The metal oxide film has two or more kinds of metal oxides having different metal elements, and the porosity of the metal oxide film is continuously changed ;
Further, the two or more kinds of metal oxides are copper oxide and zinc oxide, nickel oxide and yttria stabilized zirconia, cobalt oxide and iron oxide, titanium oxide and lanthanum oxide, cerium oxide and calcium oxide, indium oxide and vanadium oxide, A laminate comprising tantalum oxide and gadolinium oxide, chromium oxide and molybdenum oxide, or tungsten oxide and aluminum oxide .

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