JP2008060043A - Conductive composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prepare an electrode capable of detecting a material even with a small amount of detected materials or capable of handling and retaining a large amount of the treated materials although the electrode has the same degree of size as that of a conventional one. <P>SOLUTION: A conductive composition contains a solid electrolyte having hydrogen ion conductivity, alkaline metal ion conductivity, and anion conductivity or the like, an adsorbing agent such as zeolite, alumina, and silica, and a conductive metal of which the conductivity ((ion+electron) conductivity) at 20°C is at least 5 Ω<SP>-1</SP>m<SP>-1</SP>, and furthermore the conductive composition contains a catalyst such as a platinum group metal, a nickel compound, a cobalt compound, a tungsten compound, and a molybdenum compound. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a conductive composition, and more particularly to a conductive composition suitable as a material for forming various types of electrochemical devices such as gas sensors and fuel cells, and in particular, electrochemical devices.

As a material for forming an electrode in the electrochemical device, Patent Document 1 described below discloses an electrode made of a mixed composition of a metal halide and a solid electrolyte on one side of a solid electrolyte membrane as an electrode for a halogen gas sensor. ing. Further, in Patent Document 2 described later, an inert substance that hardly reacts with the decomposition gas on one side surface of a solid electrolyte membrane is used for a gas sensor that detects a decomposition gas of SF ₆ such as SF ₄ , SOF ₂ , HF, and SO _2. For example, an electrode made of gold is disclosed.

By the way, the above-mentioned conventional electrode has a simple composition such as a mixed composition of metal halide and solid electrolyte, gold, or the like, and for this reason, the electrochemical reaction in the electrode is as follows. It occurs only on the surface of the electrode, in other words, only in a plane. For this reason, when a large amount of a substance to be detected exists, it is necessary to increase the area of the electrode, and it is necessary to increase the size of the electrochemical element, which increases the production cost of the electrochemical element due to the increase in size. There was a problem of securing installation space. In addition, when the amount of reactants to be processed in the electrochemical device varies greatly over time, it is necessary to optimally control the voltage applied to the electrochemical device or the current to be applied in order to perform the target electrochemical reaction. It was. Furthermore, the electrochemical element is required to hold the required amount of a substance such as fuel at the electrode for a necessary time, such as a fuel cell, but the conventional electrochemical element has a holding capacity of the substance at the electrode. Since it is extremely small, conventional electrochemical devices are not suitable for such applications.
JP-A 62-207952 JP-A-10-26602

  In view of the above-mentioned problems in the field, the present invention is capable of detecting even a smaller amount of a substance to be detected, or handling a large amount of a substance to be processed, although it is an electrode of the same size as a conventional electrode. It is an object of the present invention to provide a conductive composition capable of forming an electrode that can be retained.

  The present invention relates to a conductive composition containing a solid electrolyte, a gas adsorbent and a conductive metal (hereinafter referred to as a first conductive composition), and a solid electrolyte, a gas adsorbent and a conductive metal. And a conductive composition containing a catalyst (hereinafter referred to as a second conductive composition).

  Since the first conductive composition of the present invention contains a solid electrolyte and a conductive metal, the conductivity as an electrode in various electrochemical devices is low frequency as will be clarified in the examples below. Underneath has good ionic conductivity. In addition, because it also contains an adsorbent, the reaction surface area inside the conductive composition becomes three-dimensional based on the presence of the adsorbent, and the increase in the reaction surface area based on the three-dimensionalization results in an electrochemical reaction. Unlike a conventional electrode that occurs only in a planar manner, it is possible to create an electrode that can handle an extremely large amount of reactants.

Embodiment Considering an example of a methanol fuel cell as an electrochemical element, in this case, it is necessary to hold an aqueous methanol solution as a fuel in an electrode, which is the first of the present invention including an adsorbent. The electrode formed of the conductive composition not only makes it industrially possible, but also realizes a significant downsizing of the methanol fuel cell. Considering an example of an HF gas sensor installed in a gas insulated switchgear filled with hexafluoride gas as an electrochemical element, this type of conventional gas sensor can measure only the HF gas concentration at the instantaneous wind speed at the time of measurement. However, when the electrode of the HF gas sensor is formed of the first conductive composition of the present invention, it can adsorb and hold a large amount of HF gas, in other words, can accumulate and hold HF gas. The total amount of HF gas generated between them, that is, the integral value of the HF gas amount with respect to time, can be quantified, whereby the life of the gas insulated switchgear can be determined with higher accuracy.

  Since the second conductive composition of the present invention further includes a catalyst in addition to the solid electrolyte, the adsorbent, and the conductive metal, in addition to the above-described effects of the first conductive composition of the present invention, It has the effect of promoting various electrochemical reactions at the electrodes of chemical elements. For example, considering the example of the methanol fuel cell, since the decomposition reaction of methanol is promoted, the power generation efficiency of the methanol fuel cell is improved.

The solid electrolyte used in the present invention may be a conventionally known or well-known one that generally exhibits ionic conductivity at a temperature lower than the melting point. For example, H ₃ Mo ₁₂ PO ₄₀ / 29H ₂ O, H _{3 W 12 PO 4 · 29H 2 O} , H 3 UO 2 PO 4 · 4H 2 O, SrCe 0.95 Yb 0.05 O 3-α, HClO 4 · 4H 2 O, Sb 2 O 5 · 4H 2 O, C _{6 H 12 N 2 (H 2} SO 4) 1.5, Li (N 2 H 5) SO 4, KOH, CsHSO 4, H 3 O + -β '' - Al 2 O 3, NH 4 + -H 3 O ⁺ β ″ -Al ₂ O ₃ , NH ₄ ⁺ -β / β ″ -Ga ₂ O ₃ , HxWO ₃ (where X is 0 to 1, the same applies hereinafter), HxMoO ₃ , (ThO ₂ ) _{0.85 (Y 2 O 3) 0.15,} La 0.96 Ca 0.04 YO 3-α ( And alpha is 0-1, hereinafter the _{same), SrCe 0.95 Yb 0.05 O 3} -α, BaCe 0.90 Nd 0.10 O 3-α, Ba 3 Ca 1.18 Nb 1.82 O 9- _α , a solid polymer electrolyte (for example, trade name manufactured by DuPont; Nafion 117), etc., a hydrogen ion conductive solid electrolyte, Li ₃ N, Li ₁₄ Zn (GeO ₄ ) ₄ , Li _3.6 Si _{0.6 P 0.4, Na 2 O · 11Al} 2 O 3, Na 2 O · 5.33Al 2 O 3, Na 3 Zr 2 Si 2 PO 4, K 2 O · 5.2Fe 2 O 3 0.8ZnO, such as Alkali metal ion conductive solid electrolyte, 7CuBr · C ₆ H ₁₂ N ₄ CH ₂ Br, Rb ₄ Cu ₁₆ I ₇ Cl ₁₃ , α-AgI, RbAg ₄ I ₅ , AgI-Ag ₂ WO ₄ , etc. Genus element Io Conductive solid _{electrolyte, CaF 2, LaF 3, (} CeF 3) 0.95 (CaF 2) 0.05, SnCl l2, PbCl 2 (+ 3% KCl), (ZrO 2) 0.9 (Y 2 O ₃ ) _0.1 , (CeO ₂ ) _0.8 (Gd ₂ O ₃ ) _0.2 , (Bi ₂ O ₃ ) _0.75 (Y ₂ O ₃ ) _0.25 , La _0.8 Sr _0.2 One kind or two or more kinds of anionic conductive solid electrolytes such as Ga _0.8 Mg _0.2 O _3-α are used.

  The adsorbent may be a conventionally known or well-known one that physically or chemically adsorbs or sorbs a gas at a solid-gas interface. For example, zeolitic, zeolite P, rhyolite, chorzeite, zeolite Naturally produced zeolites such as X, zeolite Y, soda zeolite, mordenite, chabasite, erionite, synthetic zeolites whose cations are K and Na, synthetic zeolites whose cations are Na, cations are Ca and Na Other adsorbents such as synthetic zeolite such as a certain synthetic zeolite, zeolite such as alumina, silica gel, bone charcoal, activated clay, and molecular shaping carbon are exemplified, and one or more of these are used.

As the conductive metal, a metal having a conductivity at 20 ° C. of at least 5Ω ⁻¹ · m ⁻¹ , for example, white metal such as platinum, osmium, rhodium, iridium, palladium, gold, silver, copper, nickel, cobalt , Tin or the like is used alone or in combination.

The reaction catalyst is generally a substance having a function or an action that lowers the activation energy of the reaction and promptly reaches equilibrium. For example, white metals such as ruthenium, osmium, rhodium, iridium, palladium, and platinum are used. Metal or oxide thereof, Ni, Ni ₄ Fe, Ni ₃ Fe, Ni ₂ Fe, Ni ₃ Fe ₇ , NiFe, NiFe ₃ , NiFe ₅ , Ni ₂ Co, NiCo, NiCo ₂ , Ni ₃ Ti, NiTi, Ni ₃ W, NiW, Ni ₄ Mo, Ni ₃ Mo, NiOx (where X is 0 to 1), Ni ₂ MnO ₄ , Ni _1.5 Mn _1.5 O ₄ , NiMn ₂ O ₄ , Ni _0.8 Cu _{0.2 Mn 2 O 4, Ni 0.8} Cu 0.5 Mn 2 O 4, Ni 0.33 Al 0.67 Ox, Ni 0.80 Al 0.2 _{Ox, Ni 0.87 Al 0.13 Ox,} Ni 0.89 Cu 0.11 Ox, Ni 0.77 Sn 0.23 Ox, Ni 2 FeO 4, Ni 1.5 Fe 1.5 O 4, NiFe 2 Nickel compounds such as O ₄ and NiCr ₂ O ₄ , Co, Co ₃ Fe, CoFe, CoFe ₃ , Co ₉ Ti, Co ₂ Ti, CoTi, CoTi ₂ , Co ₉ W, Co ₃ W, Co ₇ W ₆ , Co ₄ W ₆ , Co ₃ MO, Co ₇ MO ₆ , CoMO, Co ₉ Cu, Co ₃ Cu, CoCu, CoSi ₂ , and other cobalt compounds, W, WB, W ₂ B, W ₂ B ₅ , etc. compounds, Mo, MoB, MoSi _2, molybdenum compounds such _{as, NbB, TaB, TaB 2,} ZrB 2, FeSi 2, one such other compounds, such as or More seed is used.

  As can be seen from the constituent material examples of the conductive composition, nickel, cobalt, and white metal have both functions as a conductive metal and a catalyst. Therefore, the first conductive composition and the second conductive of the present invention are used. This is particularly preferable from the viewpoint of procurement of the type of material used in manufacturing the composition and simplification of the manufacturing process of the conductive composition described later.

  The first conductive composition and the second conductive composition of the present invention can be produced by mixing using at least one or two or more of a solid electrolyte, an adsorbent, a conductive metal, and a catalyst. However, examples of the mixing method include ordinary methods such as mechanical mixing and sputtering. In addition, in order for the conductive composition of the present invention to have more excellent adsorptivity and ionic conductivity under a low-frequency electric field, the first conductive composition and the second conductive composition are molded articles, etc. It is desirable that the constituents be present in close proximity to each other so that they can be handled as one solid.

  Hereinafter, some examples of specific methods for obtaining the molded product will be described. The constituent materials in the conductive composition of the present invention are all inorganic except a part of the solid electrolyte, so that a molded product is obtained separately when the inorganic solid electrolyte is employed and when the organic solid electrolyte is employed. The method will be described.

First, when the constituent materials are all inorganic, the powders of the constituent materials are mixed mechanically and uniformly to obtain a mechanical mixture, and then the mechanical mixture is subjected to high pressure, for example, 50 kg / cm ^{2 to} 1000 kg / Obtained by the high pressure compression method in which compression is performed at a pressure of about cm ^2, the first sintering method in which the mechanical mixture is sintered to such an extent that bonding between particles is caused by mass transfer based on the reduction of surface energy, and the high pressure compression method described above. A second sintering method in which the compressed material is sintered in the same manner as described above, and a sputtering method in which each target material powder or solid piece is used as a target and each target is sputtered onto a collective target assembled in a plate shape. ,and so on.

  As the powder of each constituent material subjected to the mechanical mixing, fine particles having a particle size of about 0.01 μm to 1 μm are preferable. In the present invention, the above particle diameters are all average particle diameter values measured with a Wiegner particle size analyzer. In general, the electrodes in the various electrochemical devices described above are thin with a thickness of about several 0.1 μm to 100 μm, and such a thin one can be obtained by any of the above methods. Although it is possible to slice it and further divide it, it is economically disadvantageous to do it industrially because it requires high technology and expensive equipment, so it can be desired without slicing. It is good to adjust the quantity of the mechanical mixture with which the said 1 solid-material formation method is provided so that thin-film-like 1 solid things, such as a sheet form and film shape which have thickness, may be obtained.

  Since said 2nd sintering method sinters the compression thing obtained by the said high pressure compression method, since compactization of each constituent material in the said compression thing improves further, it is preferable. In the sputtering method, a mixture of constituent materials contained in the disk-shaped collective target is obtained by colliding primary ions such as argon ions with the collective target rotated in one direction. However, the amount ratio of the constituent material in the mixture obtained by sputtering can be adjusted by adjusting the abundance ratio of the constituent material in the disk-shaped collective target at that time.

  In the case of the mechanical mixing and sintering, the conductive metal and the adsorbent may be put into the above mixing processes separately from each other, or the conductive metal is previously applied to the adsorption inner and outer surfaces of the adsorbent. Plating by electroless plating or the like may be performed as an integrated body of the adsorbent and the conductive metal. In addition, when handling as the integral, if the integral is well dispersed in the conductive composition of the present invention, the conductive metal is compared with the case where the conductive metal and the adsorbent are separately charged and mixed. Thus, there is an advantage that necessary conductivity can be obtained with a small amount. On the other hand, since a part of the adsorbing surface of the adsorbent is covered with the conductive metal, the adsorbing ability of the adsorbent is lowered. Therefore, what is necessary is just to determine the grade of plating so that the best performance can be obtained by trial and error from both the adsorption ability and electroconductivity of the electrically conductive composition of this invention. The same can be said for the handling of the adsorbent and the conductive metal, the degree of plating, and the like when an organic solid electrolyte described later is used.

  Next, the case where an organic solid electrolyte is used will be described. In this case, the organic solid electrolyte is dissolved or dispersed in a suitable organic solvent to form a paste, and then a conductive metal and adsorbent, or an adsorbent plated with a conductive metal, and a catalyst are dispersed therein. Is applied to a solid electrolyte membrane interposed between the positive and negative electrodes, and dried or sintered, for example, when the conductive composition of the present invention is used as an electrode forming material in various electrochemical devices. The way to do is good. Of course, even when an organic solid electrolyte is used, the above-described high-pressure compression method, first sintering method, second sintering method, and sputtering method are also effective.

  The blending ratio of the constituent components in the present invention is not particularly limited as long as the above-described invention object of the present invention is achieved. However, the blending ratio of other components per 100 parts by weight of the solid electrolyte is a general blending ratio. In terms of ratio, the conductive metal is 0.1 to 100 parts by weight, preferably 1 to 20 parts by weight, when it is used without being plated on the adsorbent, When used, it is 0.1 to 50 parts by weight, preferably 0.5 to 10 parts by weight. The adsorbent is 1 to 100 parts by weight, preferably 5 to 20 parts by weight. The catalyst is 1 to 500 parts by weight, preferably 10 to 100 parts by weight.

  When the first conductive composition and the second conductive composition of the present invention are used for forming electrodes in various electrochemical devices, the first conductive composition and the second conductive composition are often used. It is fixed in a state where it is electrically coupled to one or both surfaces of a solid electrolyte film made of the same material as that contained in the solid electrolyte, or made of other materials (hereinafter, the film is referred to as an element intermediate film). . The bonding can be performed by a method in which the thin film-like molded product obtained by the above-described method and the above-mentioned element intermediate film are stacked and compressed at a high pressure, or sintered. Further, when the solid electrolyte in the first conductive composition or the second conductive composition is an organic substance, an organic solvent paste of these compositions is applied to the film in the device and sintered.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. In addition, as a material used in the following examples and comparative examples, a commercial item is used, and it is used by refining it in a mortar if necessary.

Example 1.
Using H ₃ Mo ₁₂ PO ₄₀ / 29H ₂ O with a particle size of about 0.5 μm as a solid electrolyte, erionite with a particle size of about 1.5 μm as a kind of adsorbent, and platinum as a conductive metal It was. Elionite was electrolessly plated with platinum under the following conditions. The electroless plating solution was prepared by dissolving 0.5 g of dinitrodiamine platinum, 50 ml of 28% strength by weight ammonia water, and 250 ml of water under heating, and then adding 10 ml of 50% strength by weight aqueous hydroxylamine hydrochloride solution, The pH is 11.7 adjusted by adding 5 ml of hydrazine hydrate having a concentration of 80% by weight and further adding water so that the total amount becomes 400 ml. 1 g of the above erionite is immersed in 400 ml of the electroless plating solution at a temperature of 24 ° C. with stirring for 20 minutes to perform electroless platinum plating, then filtered, thoroughly washed with ion-exchanged water, and dried. An erionite having a platinum plating layer was obtained. Since 100 parts by weight of erionite before platinum plating was increased to 1 part by weight after platinum plating, 1 part by weight of the increased amount is based on the weight of platinum plating.
Next, 20 parts by weight of the platinum-plated erionite is mixed with 100 parts by weight of the H ₃ Mo ₁₂ PO ₄₀ / 29H ₂ O, and the mixture is high-pressure compressed under a pressure of 1000 kg / cm ² , and a specimen having a thickness of 50 μm. Got.

Example 2.
HClO ₄ · 4H ₂ O with a particle size of about 0.3 μm as a solid electrolyte, synthetic zeolite with a cation with a particle size of about 5 μm as an adsorbent, K and Na (trade name of JGC Universal) MFI 300) was used gold as the conductive metal. The synthetic zeolite was electrolessly plated with gold under the following conditions. The electroless plating solution is prepared by dissolving 500 ml of components of 0.02M cyano gold (I) potassium solution, 0.2M potassium cyanide, 0.2M potassium hydroxide and 0.4M potassium borohydride under heating. .
1 g of the above synthetic zeolite is immersed in 400 ml of the electroless plating solution at a temperature of 24 ° C. for 20 minutes with stirring, followed by electroless gold plating, followed by filtration, washing thoroughly with ion-exchanged water, drying, and a gold plating layer A synthetic zeolite having Since 100 parts by weight of the synthetic zeolite before gold plating was increased to 118 parts by weight after gold plating, the 18 parts by weight of the increase was based on the weight of the gold plating. Next, 20 parts by weight of the gold-plated synthetic zeolite was mixed with 100 parts by weight of the above HClO ₄ .4H ₂ O and high-pressure compressed under a pressure of 1000 kg / cm ² to obtain a test piece having a thickness of 50 μm.

Example 3.
A solid polymer electrolyte (trade name manufactured by DuPont; Nafion 117) was used as the solid electrolyte, zeolite P having a particle diameter of about 1 μm, which is a kind of zeolite, and silver as the conductive metal. The zeolite P was electrolessly plated with silver under the following conditions. That is, as an electroless plating solution, 2 g / L of silver cyanide, 75 g / L of ammonium chloride, 50 g / L of sodium citrate, and 10 g / L of sodium hypophosphite are dissolved under heating. 1 g of the above zeolite P is immersed in 400 ml of the electroless plating solution with stirring for 20 minutes to give electroless silver plating, then filtered, washed thoroughly with ion-exchanged water, and dried to form a silver plating layer. Zeolite P having was obtained. Since 100 parts by weight of zeolite P before silver plating was increased to 112 parts by weight after silver plating, the 12 parts by weight of the increase was based on the weight of silver plating.
Next, 0.1 liter of alkylbenzene oil (viscosity at 20 ° C .: 18 c.sts) per 100 parts by weight of the solid polymer electrolyte was used to obtain an alkylbenzene oil paste of the solid polymer electrolyte, and then the solid polymer was added to the paste. Injecting and mixing the silver-plated zeolite P at a ratio of 20 parts by weight per 100 parts by weight of the electrolyte to obtain a mixed paste, and further applying the mixed paste onto one side of the film made of the same material as the solid polymer electrolyte separately prepared, The coated material was sintered under the condition of 350 ° C., and a sintered film having a thickness of 30 μm was obtained.

Example 4
Synthetic zeolite (product of JGC Universal Co., Ltd.) with Na ₂ O · 11Al ₂ O ₃ with a particle size of about 13 μm as a solid electrolyte and a cation with a particle size of about 18 μm, Ca and Na, which is a kind of zeolite as an adsorbent. Copper was used as the conductive metal. The synthetic zeolite was electrolessly plated with copper under the following conditions. The electroless plating solution was adjusted to pH 12.5 by adding copper sulfate pentahydrate 15 g / L, EDTA-4Na 45 g / L, formaldehyde 15 g / L, and predetermined amounts of dipyridyl and nickel potassium cyanide as additives. Things were used. 1 g of the above synthetic zeolite is immersed in 400 ml of the electroless plating solution at a temperature of 60 ° C. with stirring for 20 minutes to perform electroless copper plating, then filtered, thoroughly washed with ion-exchanged water, dried, and copper A synthetic zeolite having a plating layer was obtained. Since 100 parts by weight of the synthetic zeolite before the copper plating was increased to 119 parts by weight after the copper plating, the 19 parts by weight of the increase was based on the weight of the copper plating. Next, 20 parts by weight of the copper-plated synthetic zeolite is mixed with 100 parts by weight of the Na ₂ O · 11Al ₂ O ₃ , and high-pressure compression is performed under a pressure of 1000 kg / cm ² to obtain a test piece having a thickness of 30 μm. Got.

Example 5.
7CuBr · C ₆ H ₁₂ N ₄ CH ₂ Br having a particle size of about 17 μm as a solid electrolyte, mordenite having a particle size of about 18 μm, which is a kind of zeolite, as an adsorbent, and platinum as a conductive metal were used. The mordenite was electrolessly plated with platinum by the same method and conditions as in Example 1. Since 100 parts by weight of mordenite before platinum plating was increased to 118 parts by weight after platinum plating, 18 parts by weight of the increased amount is based on the weight of platinum plating. Next, 20 parts by weight of the platinum-plated mordenite is mixed with 100 parts by weight of the 7CuBr · C ₆ H ₁₂ N ₄ CH ₂ Br, and high-pressure compression is performed under a pressure of 1000 kg / mm ² , and the test has a thickness of 80 μm. I got a piece.

Example 6
LaF ₃ with a particle size of about 20 μm as a solid electrolyte, synthetic zeolite (product of JGC Universal) with a cation with a particle size of about 18 μm, which is a kind of zeolite as an adsorbent, and platinum as a conductive metal It was. The synthetic zeolite was electrolessly plated with platinum by the same method and conditions as in Example 1. Since 100 parts by weight of the synthetic zeolite before the platinum plating was increased to 118 parts by weight after the platinum plating, the increased part of 18 parts by weight is based on the weight of the platinum plating. Next, 20 parts by weight of the platinum-plated synthetic zeolite was mixed with 100 parts by weight of LaF _{3 and} compressed under a high pressure of 1000 kg / cm ² to obtain a test piece having a thickness of 90 μm.

Example 7.
Li ₁₄ Zn (GeO ₄ ) ₄ having a particle size of about 20 μm as a solid electrolyte, alumina having a particle size of about 20 μm as an adsorbent, and gold as a conductive metal were used. The alumina was electrolessly plated with gold under the same conditions as in Example 2. Since 100 parts by weight of alumina before gold plating was increased to 116 parts by weight after gold plating, the increased part of 16 parts by weight is based on the weight of platinum plating.
Next, the Li ₁₄ Zn (GeO ₄ ) ₄ and the gold plating / alumina are individually compressed with high pressure at a pressure of 1000 kg / cm ² to obtain a sputtering target having a thickness of 500 μm. A 5 mm disk-shaped collective target was obtained. The ratio of the area of Li ₁₄ Zn (GeO ₄ ) ₄ in the disk-shaped aggregate target: the area of gold plating / alumina was 80:20. Thickness of 3 μm formed by mixing gold plating / alumina at a ratio of 20 parts by weight with respect to 80 parts by weight of Li ₁₄ Zn (GeO ₄ ) ₄ by a sputtering method in which argon ions collide with the disk-shaped aggregate target rotated. The test piece was obtained.

Example 8.
Rb ₄ Cu ₁₆ I ₇ Cl ₁₃ having a particle size of about 20 μm as a solid electrolyte, silica having a particle size of about 20 μm as an adsorbent, and silver as a conductive metal were used. The silica was electrolessly plated with silver under the same conditions as in Example 3. Since 100 parts by weight of silica before silver plating was increased to 114 parts by weight after silver plating, the 14 parts by weight of the increase was based on the weight of silver plating. Next, 100 parts by weight of the Rb ₄ Cu ₁₆ I ₇ Cl ₁₃ is mixed at a ratio of 20 parts by weight of the silver-plated silica and compressed under a pressure of 1000 kg / cm ² and then at 800 ° C. A specimen having a thickness of 50 μm was obtained by sintering.

Example 9.
(ZrO ₂ ) _0.9 (Y ₂ O ₃ ) _0.1 having a particle size of about 20 μm as a solid electrolyte, erionite having a particle size of about 15 μm as an adsorbent, and copper as a conductive metal were used. The erionite was electrolessly plated with copper under the following conditions. That is, as an electroless plating solution, copper sulfate pentahydrate 10 g / L, potassium potassium tartrate 40 g / L, sodium hydroxide (pH 12.5), formaldehyde 13 g / L, additive thiourea 0.1-2 mg / L Using a 20 ° C. solution, 2 g of the above erionite particles are immersed in 400 ml of the electroless plating solution with stirring for 20 minutes to perform electroless copper plating, then filtered, washed thoroughly with ion-exchanged water, and dried. Thus, erionite having a copper plating layer was obtained. Since 100 parts by weight of erionite before copper plating was increased to 121 parts by weight after copper plating, 21 parts by weight of the increase was based on the weight of copper plating. Next, with respect to 100 parts by weight of the (ZrO ₂ ) _0.9 (Y ₂ O ₃ ) _0.1 and 20 parts by weight of the copper plating erionite, the mixture is mixed under a pressure of 900 kg / cm ^2. A test piece having a thickness of 100 μm was obtained by high-pressure compression.

Example 10.
H ₃ Mo ₁₂ PO ₄₀ / 29H ₂ O having a particle size of about 20 μm as a solid electrolyte, erionite having a particle size of about 15 μm as an adsorbent, gold as a conductive metal, and Ni _{2 having a} particle size of about 1 μm as a catalyst. FeO ₄ was used. The erionite was electrolessly plated with gold by the same method and conditions as in Example 2. Since 100 parts by weight of erionite before gold plating was increased to 118 parts by weight after gold plating, the 18 parts by weight of the increase was based on the weight of gold plating. Next, 20 parts by weight of the gold-plated erionite is mixed with 100 parts by weight of the H ₃ Mo ₁₂ PO ₄₀ / 29H ₂ O, and the mixture is high-pressure compressed under a pressure of 900 kg / cm ² to obtain a test piece having a thickness of 100 μm. Got.

Example 11.
In Example 2, Ni ₄ Fe having a particle diameter of about 0.5 μm was used as a catalyst in the same manner as in the outside, but 20 parts by weight of gold-plated synthetic zeolite particles with respect to 100 parts by weight of HClO ₄ · 4H ₂ O, Ni ₄ Fe20 was mixed at a weight part ratio and compressed at a high pressure under a pressure of 800 kg / cm ² to obtain a test piece having a thickness of 100 μm.

Example 12.
Example 3 is the same as in Example 3 except that CoFe having a particle size of about 0.5 μm was used as a catalyst, and 20 parts by weight of silver-plated zeolite P and 40 parts by weight of CoFe per 100 parts by weight of the solid polymer electrolyte. Application and sintering were carried out at a ratio to obtain a sintered film having a coating thickness of 120 μm.

Example 13.
Example 4 is the same as in Example 4 except that MoB having a particle size of about 0.5 μm was used as a catalyst, and 20 parts by weight of copper-plated zeolite P and 40 parts by weight of MoB per 100 parts by weight of the solid polymer electrolyte. Application and sintering were carried out at a ratio to obtain a sintered film having a thickness of 100 μm.

Example 14.
In the same manner as in Example 5, except that NiCo ₂ having a particle size of about 0.3 μm was used as a catalyst, 20 parts by weight of platinized mordenite with respect to 100 parts by weight of 7CuBr · C ₆ H ₁₂ N ₄ CH ₂ Br Were mixed at a rate of 1000 kg / cm ² and compressed under high pressure to obtain a test piece having a thickness of 80 μm.

Example 15.
Example 6 is the same as in Example 6 except that NiCo ₂ having a particle size of about 0.5 μm was used and mixed at a ratio of 20 parts by weight of platinum-plated synthetic zeolite mordenite to 100 parts by weight of LaF _3. Then, high-pressure compression was performed under a pressure of 900 kg / cm ² to obtain a test piece having a thickness of 100 μm.

Example 16.
In Example 7, 20 parts by weight of gold-plated alumina with respect to 100 parts by weight of Li ₁₄ Zn (GeO ₄ ) _{4 in} the same manner and conditions except that Co ₉ Ti having a particle size of about 0.3 μm was used as a catalyst. Co ₉ Ti was 40 parts by weight, and a test piece having a thickness of 1 μm was obtained by the same sputtering method.

Example 17.
Example 8 is the same as in Example 8 except that MoSi ₂ having a particle size of about 0.5 μm was used as a catalyst. Silver plating / silica 20 with respect to 100 parts by weight of Rb ₄ Cu ₁₆ I ₇ Cl ₁₃ was used. A test piece having a thickness of 50 μm was obtained by mixing at a ratio of 30 parts by weight with 30 parts by weight of MoSi ₂ and compressing and sintering under high pressure.

Example 18.
In Example 9, Ni ₃ W having a particle size of about 0.2 μm was used as a catalyst, and copper-plated erionite 20 was added to 100 parts by weight of (ZrO ₂ ) _0.9 (Y ₂ O ₃ ) _0.1. Part by weight and 30 parts by weight of Ni ₃ W were mixed and high-pressure compressed under a pressure of 800 kg / cm ² to obtain a test piece having a thickness of 100 μm.

Comparative Example 1.
Comparative Example 1 is different from Example 1 in that no erionite is used, and is otherwise the same as Example 1, except that the particle size is 0 with respect to 100 parts by weight of H ₃ Mo ₁₂ PO ₄₀ · 29H ₂ O. 0.1 μm of platinum was mixed at a ratio of 3.4 parts by weight, which was the same amount as in Example 1, and high-pressure compressed under a pressure of 1000 kg / cm ² to obtain a specimen having a thickness of 50 μm.

Comparative Example 2.
Comparative Example 2 is different from Example 3 in that zeolite P is not used, and is otherwise the same as Example 3, except that the paste in Example 3 has a particle size of 0 per 100 parts by weight of the solid polymer electrolyte. .1 μm of silver particles are charged and mixed at a ratio of 3.6 parts by weight, which is the same amount as in Example 3, to obtain a mixed paste, and the same material as the solid polymer electrolyte prepared separately. The coated material was applied on one side of the film, and the coated material was sintered at 350 ° C. to obtain a sintered film having a thickness of 30 μm.

Comparative Example 3.
Comparative Example 3 differs from Example 8 in that silica is not used, and is otherwise the same as Example 8, except that the particle size is 0.1 μm with respect to 100 parts by weight of Rb ₄ Cu ₁₆ I ₇ Cl _13. The silver particles were mixed at a ratio of 3.4 parts by weight, which was the same amount as in Example 8, compressed at a high pressure under a pressure of 1000 kg / cm ² , and then sintered at 800 ° C. to a thickness of 50 μm. The test piece was obtained.

Comparative Example 4.
Comparative Example 4 differs from Example 16 in that alumina is not used, and is otherwise the same as Example 16, except that the particle size is 0.1 μm with respect to 100 parts by weight of Li ₁₄ Zn (GeO ₄ ) _4. A test piece having a thickness of 1 μm was obtained by the same sputtering method with a proportion of 16 parts by weight of the same gold particles as in Example 16 and 40 parts by weight of Co ₉ Ti.

With respect to each molded product obtained in Examples 1 to 18 and Comparative Examples 1 to 4, ionic conductivity, gas adsorbing ability, and moisture adsorbing ability were measured under the following test conditions, and the measurement results thereof. Are summarized in the table of FIG.
(Ion + Electron) Conductivity: Conductivity (Ω ⁻¹ · m ⁻¹ ) measured at a temperature of 20 ° C. and a frequency of 1 kHz. Ionic conductivity: Determined by measuring the ratio of ion current by Tubandt method.
Gas adsorption capacity: The test piece was vacuum-treated at 100 ° C. under a high vacuum of 0.1 mmHg or higher for 2 hours, then kept at room temperature under the high vacuum for 2 hours to cool and dry. The piece was held in NO ₂ gas at a temperature of 20 ° C. for 2 hours, the weight difference of the test piece before and after the 2 hour holding was measured, and the weight difference was taken as the gas adsorption capacity of NO ₂ gas.
Moisture adsorption ability: The test piece was vacuum-treated at 100 ° C. under a high vacuum of 0.1 mmHg or higher for 2 hours, then kept at room temperature under the high vacuum for 2 hours to cool and dry. The piece was held in a room at a temperature of 20 ° C. and a relative humidity of 50% for 2 hours, and the weight difference of the test piece before and after the 2 hour holding was measured.

  From FIG. 1, since Comparative Examples 1 to 4 do not contain an adsorbent, the proportion of the conductive metal increases accordingly, so that the ionic conductivity is superior to that of Examples 1 to 18, but the gas adsorption capacity. In addition, there is a disadvantage that the moisture adsorption capacity is extremely low. On the other hand, in Examples 1-18, although it is inferior to Comparative Examples 1-4 in ionic conductivity, it still has sufficient value for using with the electrode for electrochemical elements, and also the conventional electrochemical It can be seen that the device electrode has a high level of gas adsorbing ability and moisture adsorbing ability that cannot be found at all.

  As mentioned above, although this invention was demonstrated by Embodiment 1-18 and Comparative Examples 1-4, this invention is not limited to those embodiment, The subject in this invention and the mind of a solution means were followed. Various variations are included. For example, the solid electrolyte, the adsorbent, the conductive metal, and the catalyst may be those other than those used in Embodiments 1 to 18, and in Embodiments 1 to 18, the solid electrolyte, the adsorbent, and the conductivity. One type of material was used for both the metal and the catalyst, but it was a mixture of two or more solid electrolytes, two or more adsorbents, two or more conductive metals, and two or more catalysts. May be.

The conductive composition of the present invention includes various NOx gas, ammonia gas, halogen gas, various gases such as SF ₆ decomposition gas, various inorganic compounds, in addition to NO ₂ and moisture shown in the above examples. Since it has a function of adsorbing the aqueous solution, alcohol, lower hydrocarbon oil, or other various liquids, in addition to the methanol fuel cell and the HF gas sensor exemplified above, other than the NOx detection sensor and the methanol fuel cell. It is expected to be used as an electrode forming material in various fuel cells, indoor humidity detection and adjustment devices, or other electrochemical devices and elements.

It is a table | surface which shows the ionic conductivity, gas adsorption ability, and water | moisture-content adsorption capacity of Example 1- Example 18 of this invention.

Claims (6)

  A conductive composition comprising a solid electrolyte, an adsorbent, and a conductive metal.   2. The solid electrolyte is at least one selected from a hydrogen ion conductive solid electrolyte, an alkali metal ion conductive solid electrolyte, a group 1b metal ion conductive solid electrolyte, and an anion conductive solid electrolyte. The electroconductive composition as described.   2. The conductive composition according to claim 1, wherein the adsorbent is at least one selected from zeolite, alumina, and silica. 2. The conductive composition according to claim 1, wherein the conductive metal has a conductivity at 20 ° C. of at least 5Ω ⁻¹ m ⁻¹ .   The electrically conductive composition of Claims 1-4 containing a catalyst. 6. The conductive composition according to claim 5, wherein the catalyst is at least one selected from platinum group metals, platinum group metal compounds, nickel, nickel compounds, cobalt, cobalt compounds, tungsten, tungsten compounds, molybdenum, and molybdenum compounds.

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