JP4861633B2 - Method for producing carbon / tin oxide nanocomposite - Google Patents

Description

  The present invention relates to a method for producing an inorganic carrier / metal or inorganic carrier / metal oxide nanocomposite used as an electrical wiring material, electrical resistor, capacitor design material, various sensors, catalysts, electrodes, microreactor components, and the like. .

  The smallest unit that expresses the function and performance of a material is mainly in the nano-region, and there are remarkable developments in recent years. However, the nanomaterial itself is not used in bulk, but is used by being supported on some kind of carrier or the like. That is, it can be said that the practical stage was reached only when the carrier was supported in a highly dispersed state. For this reason, the process of compositing different types of components such as inorganic / organic, inorganic / inorganic, and inorganic / metal at the nanoscale is a very effective technique for achieving high-performance materials (Non-patent Document 1). ).

  In the synthesis of inorganic / organic nanocomposites, a sol-gel method is generally used. A metal source such as a metal alkoxide, acetate, or inorganic salt is dissolved in a solvent such as alcohol, and an acid or base, water, and necessary organics are used as a catalyst. It has been reported that an inorganic / organic complex can be easily obtained by preparing a homogeneous solution with components added and then hydrolyzing at room temperature or under heating (Non-patent Document 2).

  In addition, a method for synthesizing an inorganic / organic nanocomposite using a micelle solution or liquid crystal having a specific shape made by a surfactant as a template has been developed and reported (Non-patent Document 3). Furthermore, the inorganic carrier / metal and inorganic carrier / metal oxide nanocomposites are conventionally impregnated or impregnated with a method of directly mixing an inorganic carrier such as carbon and metal or metal oxide fine particles prepared by a sol-gel method or the like. It has been reported that the adsorbed metal component is synthesized by a reaction method, or the deposited component is baked (non-patent document 4).

However, these conventional techniques related to composites using inorganic components as carriers are as follows:
(I) component particles agglomerate during mixing;
(Ii) Precipitated particles are enlarged due to the epitaxial effect of the carrier.
(iii) It is not easy to make the particles ultrafine or highly dispersed due to the fact that the particles aggregate or grow due to the heating effect during firing. This technology has not yet been established.

Shinichi Shinhara, Nanomaterials Frontline, Chemical Doujin, Kazuyuki Hirao, 147-155, 2002 Sakuo Sakuo, Application of the sol-gel method, Agne Jofusha, 1-239, 1997 Tsuyoshi Kijima, “Development of functional fine particles and nanomaterials”, Frontier Publishing Co., Ltd., p. 57-68, 2004 Miura Norio, Complete collection of carbon technology for electronics, Technical Information Association, 427-438, 2004

  The present invention is based on the above-described prior art, and reports on the method for producing an inorganic carrier / metal or inorganic carrier / metal oxide nanocomposite, with the prior art in mind, The present invention intends to provide a novel production method in which metal or metal oxide nanoparticles are supported in a highly dispersed state. Accordingly, the present invention intends to provide a new material that contributes to electric wiring materials, electric resistors, capacitor design materials, various sensors, catalysts, electrodes, microreactor components, and the like.

  The inventors previously added malonic acid to a mixture of furfuryl alcohol (FFA) and the surfactant didodecyldimethylammonium bromide (DDAB), polymerized by heating, and then heated in an inert gas, Inspired by finding that oriented lamellar carbon can be obtained (Non-Patent Document 5), the starting reaction mixture is mixed with a tin oxide raw material, and heated to polymerize the polymer composite and tin oxide. In addition, when this composite was heated in an inert gas to produce a composite material of carbon and tin oxide, the nanoscale size of the added tin oxide was reduced. We found that nanocomposites with highly dispersed nanoparticles were produced.

Therefore, the metal or metal oxide to be used, the surfactant, the organic monomer as the polymer precursor, the type of the organic acid, and the process conditions for compositing the polymer composite by the heat polymerization reaction with the metal or metal oxide, As a result of diligent research on conditions for thermally decomposing this complex, the present invention has been achieved.
M.M. Uota and 4 others, Carbon, 42, 2207-2213, 2004

  That is, one or more metals having a diameter of 500 μm or less selected from the group consisting of various metals including tin and copper, or the group consisting of various metal oxides including tin oxide and copper oxide, or A reaction mixture comprising metal oxide particles, an organic halide having a surfactant as a typical example, an organic monomer serving as a polymer precursor, a low polymer, and an organic acid is prepared, and then the reaction mixture is heated at 100 to 300 ° C. More preferably, it is polymerized by reacting at 150 to 250 ° C., and this polymer is thermally decomposed and carbideized at 350 to 1000 ° C., more preferably 500 to 700 ° C. At the same time, the metal or metal oxide is halogenated. The metal or metal oxide is converted into an inorganic carrier by the above-described process of refining to a diameter of 1 to 100 nm by a reaction that generates a low boiling point product with Method for producing a highly dispersed nano-composite was developed.

  In this nanocomposite, metal or metal oxide particles on the order of μm react with halogen ions, the generated metal halide evaporates, and the remaining metal or metal oxide component is refined into nanoparticles of several nm. It was found that The mechanism by which this unique refining reaction occurs is that the halogen ions in the reaction mixture act selectively on the metal component, react with the metal component and become a low-boiling metal halide, which is removed by evaporation. Compared to those produced by the method, it has significantly better dispersibility. That is, it is formed by producing nano-level minute highly dispersible inorganic carrier / metal and inorganic carrier / metal oxide nanocomposites.

The present invention relates to fine metal oxide particles made of tin oxide , a polymer precursor solution containing furfuryl alcohol that uniformly disperses the metal oxide particles, and the metal oxide in the polymer precursor solution. A step of preparing a reaction mixture comprising a halogen-containing quaternary amine compound, which is a surfactant containing halogen that uniformly disperses particles , and an organic acid, malonic acid , and heating the reaction mixture to A process of polymerizing a molecular precursor to polymerize, and heating the polymerized product to carbonize it, and a metal oxide (tin oxide) contained therein reacts with a halogen to produce a low-boiling product. Of carbon / tin oxide nanocomposite, in which ultrafine tin oxide particles having a diameter of 1 to 100 nm are highly dispersed in carbon consisting of a step of refining to a diameter of 1 to 100 nm It is a production method.

Here, metallic oxides, reacts with the halogen, fine metal oxide is a tin oxide to produce a low-boiling compounds. The size of this acid halide grains, at the stage of preparing the starting reaction mixture, but is obtained that highly dispersed as those small in diameter, it is possible to use those of 500μm or less. If it is small, the product obtained after the reaction also becomes small or easily reaches the nm level in a short time, and it is preferable to use a micron level or submicron level. As the polymer precursor , furfuryl alcohol that can be polymerized by copolymerization, an organic acid, or a low molecular weight polymer thereof can be used and blended . Interfacial active agent, in preparing the reaction mixture, or metallic oxide particles agglomeration, are used in order to uniformly disperse to prevent or segregated, decomposed by heating, reactive halogen release It must be possible. Examples of such a surfactant include a surfactant made of a quaternary amine compound containing halogen.

Further, the invention derived from this invention, the fine metal oxide particles composed of fine acid tin, said metal oxide and polymer precursor solution to uniformly disperse the particles, polymer precursor solution the metal oxide surfactant containing a halogen to particles uniformly dispersed, and preparing a reaction mixture comprising an inorganic carrier, and heating the reaction mixture, polymerization by polymerizing the polymeric precursor to A step of heating, polymerizing the polymerized product, and a metal or metal oxide contained therein is refined to a diameter of 1 to 100 nm by a reaction that generates a low boiling point product with a halogen, the responsible body made of an inorganic carrier and carbon consisting of ultra fine Hosokin genus oxide particles with a diameter 1~100nm is highly dispersed, inorganic carrier (and carbon) / method for producing a tin oxide nanocomposite There is .

Further, the following uses of the carbon / tin oxide nanocomposite of the present invention are presented .

An electrical material characterized in that the carbon / tin oxide nanocomposite of the present invention is exclusively used as an electrical wiring material, an electrical resistor, or a design material for a capacitor.

A sensor design material, wherein the carbon / tin oxide nanocomposite of the present invention is used as a material in various sensor designs.

A catalyst material comprising the carbon / tin oxide of the present invention .

An electrode material, wherein the carbon / tin oxide nanocomposite of the present invention is exclusively used as an electrode material for electrolysis.

A microreactor using the carbon / tin oxide nanocomposite of the present invention as a microreactor constituent member.

The present invention, consisting of a 1~100nm level class ultrafine Hosokin genus oxide particles obtained by carrying uniformly dispersed to as (tin oxide particles) inorganic support (carbon carrier), ultrafine particles altitude now it can provide a Nanokonpoji' door that is dispersed in. As a result, nanoparticles have progressed to a practical level of practical use, and the usability of nanoparticles has further increased. In the future, the various properties of nanoparticles will become much easier to use. It is expected that reaching the level will be accelerated.

The invention of this application has the above characteristics, and will be specifically described below. However, these examples merely disclose one aspect of the present invention, and are not intended to limit the present invention. That is, as described above, the aim of the present invention is to provide a carbon support / tin oxide nanocomposite.

Further, the outline of the production method is at least an organic halide (quaternary amine compound containing halogen) such as tin oxide particles, cetyltrimethylammonium bromide, didodecyldimethylammonium bromide, an organic monomer (full The precursor obtained by mixing a reaction mixture composed of ( furyl alcohol) and an organic acid (malonic acid) under appropriate conditions is fired to derive a highly dispersed nanocomposite, and the precursor is constructed. The optimum temperature and mixing conditions vary depending on the characteristics of the target metal species or metal oxide species and the surfactant used. On the other hand, an Example shows only the example of the aspect with respect to this invention to the last, and the manufacturing method of this invention should not be limited by this Example.

FIG. 1 is an observation photograph of a carbon / tin oxide nanocomposite, which is an example of the present invention, by a transmission electron microscope. According to this, it is observed that the carbon / tin oxide nanocomposite of the present invention exhibits high dispersion. Is done. FIG. 2 is an X-ray diffraction diagram of a carbon / tin oxide nanocomposite that is an example of the present invention. According to this, the carbon / tin oxide nanocomposite of the present invention is so finely divided and highly dispersed that it cannot be detected by X-ray diffraction. It shows that it has become. Further, the TG curve of FIG. 3 shows that the SnO ₂ content of the carbon / tin oxide nanocomposite is 2.68 wt%.

Example 1;
Furfuryl alcohol (FFA) and didodecyldimethylammonium bromide (DDAB) were mixed at a molar ratio of 2: 1, sonication was performed, and 5 wt% of SnO was added to FFA. Next, malonic acid (MA) was added at a molar ratio of FFA: MA = 2: 1 and reacted at 40 ° C. The obtained product was reacted at 200 ° C. for 5 hours and then calcined in air at 300 ° C. for 5 hours and then in a nitrogen atmosphere at 600 ° C. for 5 hours to obtain a carbon / tin oxide nanocomposite. When TEM observation of a sample heated at 600 ° C. in nitrogen was performed, as shown in FIG. 1, crystalline fine particles having a diameter of 5 nm were dispersed on amorphous carbon to form a carbon / metal oxide nanocomposite. I understood. As shown in FIG. 2A, no peak due to Sn and SnO ₂ was observed in the XRD pattern of the sample. Also shows that SnO ₂ content of 2.68wt% from TG curve of FIG.

The present invention, in addition to the above examples, stacked Experiment variety, as a result of organizing data obtained, metallic oxides (tin oxide), a complex of a polymer containing a surfactant as precursors by firing, in which it was confirmed that the production of non-machine support / metal oxide nanocomposite of much highly dispersed than those prepared by the conventional method.

The present invention has succeeded in developing a novel method for producing a non-machine support / metal oxide nanocomposite, its industrial significance is very large. Disclosure of detailed physical properties, specific data on various characteristics and effects in various technical fields, and research and development of new technical possibilities and developments related to this will be conducted in the future. a large place to wait, but those that are left, intended to provide a convenient and novel non-machine support / metal oxide nanocomposite of the manufacturing process, exerts an excellent function and effect in various fields, greatly It is expected to contribute to industrial development.

  That is, examples include new materials that contribute to electrical wiring materials, electrical resistors, capacitor design materials, various sensors, catalysts, electrodes, microreactor components, etc., and are used as basic industrial materials that are not limited to specific fields. I can do it. Of course, it is also used for other purposes, and it is expected that it will be widely used in the future as an excellent material with various properties and contribute to the development of industry.

Observation by transmission electron microscope of carbon / tin oxide nanocomposite of the present invention X-ray diffraction pattern of carbon / tin oxide nanocomposite of the present invention TG weight reduction diagram of carbon / tin oxide nanocomposite of the present invention

Claims (1)

Tin oxide particles, which are fine metal oxide particles, a polymer precursor solution containing furfuryl alcohol that uniformly disperses the tin oxide particles, and the tin oxide particles uniformly dispersed in the polymer precursor solution A step of preparing a reaction mixture comprising a halogen-containing quaternary amine compound which is a surfactant containing halogen and an organic acid, malonic acid , and heating the reaction mixture to polymerize the polymer precursor The polymerized product is heated to carbonize and the tin oxide contained therein reacts with the halogen to produce a low-boiling product with a diameter of 1 to 100 nm. Of carbon / tin oxide nanocomposites in which ultrafine tin oxide particles with a diameter of 1 to 100 nm are highly dispersed in carbon comprising Law.