JP2010238547A - Catalyst carrier for fuel cell, catalyst for fuel cell, and electrode for fuel cell - Google Patents

Catalyst carrier for fuel cell, catalyst for fuel cell, and electrode for fuel cell Download PDF

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JP2010238547A
JP2010238547A JP2009085381A JP2009085381A JP2010238547A JP 2010238547 A JP2010238547 A JP 2010238547A JP 2009085381 A JP2009085381 A JP 2009085381A JP 2009085381 A JP2009085381 A JP 2009085381A JP 2010238547 A JP2010238547 A JP 2010238547A
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Katsuhiko Saguchi
勝彦 佐口
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Equos Research Co Ltd
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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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Abstract

<P>PROBLEM TO BE SOLVED: To provide a catalyst carrier for a fuel cell which is made from a new material instead of carbon particles, and wherein a principal catalyst is hardly desorbed and catalyst activity is hardly lowered, a catalyst for a fuel cell using the catalyst carrier, and an electrode for the fuel cell using the catalyst. <P>SOLUTION: The catalyst carrier for the fuel cell is made of a perovskite type complex metal oxide particles with conductivity. A stratified perovskite expressed by general formulas: A<SB>2</SB>BO<SB>4</SB>(for example, La<SB>2-X</SB>SrCuO<SB>4</SB>and La<SB>2-X</SB>BaCuO<SB>4</SB>) and 3ABO<SB>3</SB>-A<SB>2</SB>B<SB>2</SB>O<SB>5</SB>(La<SB>4</SB>BaCu<SB>5</SB>O<SB>13.4</SB>) is especially preferable. What a principal catalyst made of noble metal such as Pt is carried by the stratified perovskite can be used as the catalyst for the fuel cell. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

本発明は、層状ペロブスカイト型複合金属酸化物を利用した燃料電池用触媒担体、燃料電池用触媒、及び燃料電池用電極に関する。   The present invention relates to a fuel cell catalyst carrier, a fuel cell catalyst, and a fuel cell electrode using a layered perovskite-type composite metal oxide.

近年、新たな排ガス用触媒として、一般式ＡＢＯ３等で表されるペロブスカイト型複合酸化物の結晶格子におけるＢサイトをＰｔ、Ｐｄ、Ｒｈ等の貴金属で一部置換した化合物が提案されている（特許文献１）。この触媒は触媒活性が高く、耐硫黄被毒性も向上することが知られている。さらには、こうした結晶子中に貴金属元素を含むペロブスカイト型複合酸化物微粒子の結晶子サイズが１〜２０ｎｍまで小さくなった場合、３００°Ｃ以下においても電極触媒としての特性が発現することから、これをカーボン粒子に担持させることにより、燃料電池用の触媒として用いることが提案されている（特許文献２、３）。また、このような結晶子中に貴金属元素を含むペロブスカイト型複合酸化物微粒子は自己再生機能を有しており、従来の金属白金粒子触媒とは異なり、白金粒子の凝集・固着による早期の特性の劣化が起こらないと考えられる。劣化後の特性を十分に保つために、電極用触媒としては一般的に、担体であるカーボン粒子に対して５０重量％もの白金を使用しなければならない現状に対して、特許文献２に記載の微粒子担持カーボン粒子では白金粒子の劣化が起こらず、より少ない貴金属（主として白金）で電極用触媒とすることが可能となる。 In recent years, as a new exhaust gas catalyst, a compound in which the B site in the crystal lattice of a perovskite complex oxide represented by the general formula ABO 3 or the like is partially substituted with a noble metal such as Pt, Pd, or Rh has been proposed ( Patent Document 1). This catalyst is known to have high catalytic activity and improve sulfur poisoning resistance. Furthermore, when the crystallite size of the perovskite type complex oxide fine particles containing a noble metal element in such a crystallite is reduced to 1 to 20 nm, the characteristics as an electrode catalyst are exhibited even at 300 ° C. or lower. It has been proposed to be used as a catalyst for a fuel cell by supporting carbon on carbon particles (Patent Documents 2 and 3). In addition, perovskite-type composite oxide fine particles containing a noble metal element in such a crystallite have a self-regenerative function, and unlike conventional metal platinum particle catalysts, early characteristics due to aggregation and fixation of platinum particles are achieved. Deterioration is not expected. In order to sufficiently maintain the characteristics after deterioration, as a catalyst for electrodes, generally, as much as 50% by weight of platinum with respect to carbon particles as a support must be used. The fine particle-supported carbon particles do not deteriorate the platinum particles, and can be used as an electrode catalyst with a smaller amount of noble metal (mainly platinum).

特開２００４−３２１９８６号公報JP 2004-321986 A 特開２００７−１１２６９６号公報JP 2007-112696 A 特開２００８−４２８６号公報JP 2008-4286 A

上記特許文献２、３に記載されている燃料電池用触媒は、ペロブスカイト型複合酸化物微粒子を主触媒としてカーボン担体に担持させて使用するものであり、ペロブスカイト型複合酸化物微粒子を触媒の担体として用いるという発想はなかった。   The catalysts for fuel cells described in Patent Documents 2 and 3 are used by supporting perovskite composite oxide fine particles on a carbon support as a main catalyst, and using the perovskite composite oxide fine particles as a catalyst support. There was no idea of using it.

また、上記結晶子中に貴金属元素を含むペロブスカイト型複合酸化物微粒子をカーボンに担持させた燃料電池用触媒では、ペロブスカイト型複合酸化物微粒子が脱離し易く、触媒活性が低下しやすいという問題があった。   In addition, the fuel cell catalyst in which the perovskite-type composite oxide fine particles containing a noble metal element in the crystallite are supported on carbon has a problem that the perovskite-type composite oxide fine particles are easily detached and the catalytic activity is easily lowered. It was.

これは、次のような理由によるものと推測される。まず第1の原因としては、カーボン粒子が疎水性であるため、親水性を有するペロブスカイト型複合酸化物微粒子との間の結合力が弱く、脱離し易いことが挙げられる。さらに第2の原因として、カーボン粒子自身の酸化反応によって炭酸ガスとなって侵食されることが挙げられる。すなわち、固体高分子型燃料電池を駆動させた場合、カソード電極では電極反応によって生じた水が溜まり、電極中のプロトンの移動によりアノード側電極に逆拡散する。この逆拡散によって移動した水は、アノード極中に滞留して燃料ガスである水素の供給を阻害する。このためアノード極では水素ガスの拡散律速が発生し、プロトンの生成が阻害され、カソード側で必要となるプロトンの供給を補うため、アノード極側のカーボン粒子自身が酸化され、炭酸ガスとプロトンとが生成する。
一方、カソード極側においては、酸素還元反応の活性化エネルギーの大きいことから、カソードに過電圧（抵抗）が生じ、０．８Ｖ以上の貴電位環境となった場合や、起動停止／連続運転を繰返すうちに、カーボン担体の腐食が発生する。特に、カソード側では、アノード側で水素から得たプロトンがカソード側に供給される酸素と結合して水を生成するため、Ｃ＋２Ｈ２Ｏ→ＣＯ２＋４Ｈ＋＋４ｅ−等の二酸化炭素を生成する反応が進行すると考えられる。
こうして、カソード極及アノード極の両極において触媒担体であるカーボン粒子が炭酸ガスまで酸化され、侵食されることにより、足場を失ったペロブスカイト型複合酸化物微粒子が脱離するのである。 This is presumably due to the following reasons. The first cause is that the carbon particles are hydrophobic, so that the bonding force with the hydrophilic perovskite complex oxide fine particles is weak and easy to be detached. Furthermore, as a second cause, carbon dioxide gas is eroded by the oxidation reaction of the carbon particles themselves. That is, when the polymer electrolyte fuel cell is driven, water generated by the electrode reaction is accumulated in the cathode electrode, and is back-diffused to the anode side electrode by movement of protons in the electrode. The water moved by the reverse diffusion stays in the anode electrode and obstructs the supply of hydrogen as a fuel gas. For this reason, diffusion rate control of hydrogen gas occurs at the anode electrode, the generation of protons is hindered, and the supply of protons necessary on the cathode side is supplemented, so that the carbon particles themselves on the anode electrode side are oxidized, and carbon dioxide gas and protons Produces.
On the other hand, since the activation energy of the oxygen reduction reaction is large on the cathode electrode side, an overvoltage (resistance) is generated at the cathode, resulting in a noble potential environment of 0.8 V or more, and start / stop / continuous operation is repeated. Over time, corrosion of the carbon support occurs. In particular, on the cathode side, protons obtained from hydrogen on the anode side combine with oxygen supplied to the cathode side to generate water, so that carbon dioxide such as C + 2H 2 O → CO 2 + 4H + + 4e − is generated. Is considered to progress.
In this way, the carbon particles as the catalyst carrier are oxidized to carbon dioxide gas at both the cathode electrode and the anode electrode, and the perovskite complex oxide fine particles that have lost the scaffold are detached.

本発明は、上記従来の実情に鑑みてなされたものであって、カーボン粒子に代わる新たな材料からなる燃料電池用触媒の担体を提供することを解決すべき課題としている。また、主触媒が脱離し難く、触媒活性が低下し難い燃料電池用触媒の担体、それを用いた燃料電池用触媒及びそれを用いた燃料電池用電極を提供することを他の解決すべき課題の一つとしている。   The present invention has been made in view of the above-described conventional situation, and an object to be solved is to provide a support for a catalyst for a fuel cell made of a new material replacing carbon particles. Another object to be solved is to provide a support for a fuel cell catalyst in which the main catalyst is difficult to desorb and the catalyst activity is difficult to decrease, a fuel cell catalyst using the same, and a fuel cell electrode using the same. One of them.

本発明の燃料電池用触媒担体は、導電性を有するペロブスカイト型複合金属酸化物微粒子からなることを特徴とする。   The catalyst support for a fuel cell according to the present invention is characterized by comprising conductive perovskite-type composite metal oxide fine particles.

本発明の燃料電池用触媒担体は、導電性を有するペロブスカイト型複合金属酸化物微粒子からなるため、電極反応で生じた電子を外部回路に導いたり、外部回路から電子を取り入れて電極還元反応に用いたりするための電子伝導パスを確保することができる。また、ペロブスカイト型複合金属酸化物自身がすでに酸化体であるため、カーボン担体のように酸化によって浸食されるということがない。さらには、ペロブスカイト型複合金属酸化物は親水性であり、同じく親水性であるＰｔ等の貴金属主触媒を担持させた場合、親和力で強く結びつくため、主触媒が脱離しにくく、このため触媒活性の経時的な劣化起こり難い。   Since the catalyst support for fuel cell of the present invention is composed of conductive perovskite type composite metal oxide fine particles, electrons generated in the electrode reaction are led to an external circuit, or electrons are taken from the external circuit and used for an electrode reduction reaction. Can be secured. In addition, since the perovskite complex metal oxide itself is already an oxidant, it is not eroded by oxidation like a carbon carrier. Furthermore, the perovskite-type composite metal oxide is hydrophilic, and when a noble metal main catalyst such as Pt, which is also hydrophilic, is supported, it is strongly bound by affinity, so that the main catalyst is difficult to desorb, so that the catalytic activity is improved. Less likely to deteriorate over time.

導電性を有するペロブスカイト型複合金属酸化物微粒子は、層状ペロブスカイトであることが好ましい。ここで、層状ペロブスカイトとは、ペロブスカイト型結晶構造を有する結晶のうち、結晶の成長方向が（１００）面又は（１１０）面の方向に、２次元シート状に広がっているものをいう。具体的には、一般式Ａ２ＢＯ４及び／又は３ＡＢＯ３・Ａ２Ｂ２Ｏ５で表されるペロブスカイトである。こうした層状ペロブスカイトは、一般に電子伝導性が良好となり、燃料電池における触媒上での電極反応において必要な電子伝導パスの形成を可能とするからである。 The conductive perovskite complex metal oxide fine particles are preferably layered perovskites. Here, the layered perovskite refers to a crystal having a perovskite crystal structure in which the growth direction of the crystal spreads in a two-dimensional sheet shape in the direction of (100) plane or (110) plane. Specifically, it is a perovskite represented by the general formula A 2 BO 4 and / or 3ABO 3 .A 2 B 2 O 5 . This is because such a layered perovskite generally has good electron conductivity and enables formation of an electron conduction path necessary for an electrode reaction on a catalyst in a fuel cell.

本発明の燃料電池用触媒担体に主触媒としての金属を担持させることにより、燃料電池用触媒となる。また、さらにこの燃料電池用触媒を燃料電池の触媒層の成分として用いることができる。   A fuel cell catalyst is obtained by supporting a metal as a main catalyst on the fuel cell catalyst carrier of the present invention. Further, this fuel cell catalyst can be used as a component of the catalyst layer of the fuel cell.

燃料電池用の膜電極接合体（ＭＥＡ）の模式断面図である。It is a schematic cross section of the membrane electrode assembly (MEA) for fuel cells.

＜燃料電池用触媒担体＞
本発明の燃料電池用触媒担体は、導電性のペロブスカイト型複合金属酸化物微粒子からなる。ペロブスカイト型複合酸化物の一般式としては、一般的にはＡＢＯ3やで表されるが、その他Ａ２ＢＯ４や３ＡＢＯ３・Ａ２Ｂ２Ｏ５で表されるものもある。一般式がＡ２ＢＯ４や３ＡＢＯ３・Ａ２Ｂ２Ｏ５で表されるのは層状ペロブスカイトであり、導電性に優れることから、特に好適に用いることができる。Ａ２ＢＯ４で表される層状ペロブスカイトとしては、例えばLa2-XSrCuO4やLa2-XBaCuO4等が挙げられる（ここで、Ｘの範囲は０．１〜１．９である）。また、３ＡＢＯ３・Ａ２Ｂ２Ｏ５で表される層状ペロブスカイトとしては、La4BaCu5O13.4等が挙げられる。 <Catalyst carrier for fuel cells>
The catalyst carrier for a fuel cell of the present invention is composed of conductive perovskite type composite metal oxide fine particles. The general formula of the perovskite type complex oxide is generally represented by ABO 3 , but may be represented by A 2 BO 4 or 3ABO 3 .A 2 B 2 O 5 . The general formula represented by A 2 BO 4 or 3ABO 3 .A 2 B 2 O 5 is a layered perovskite, and is excellent in conductivity, and therefore can be particularly preferably used. Examples of the layered perovskite represented by A 2 BO 4 include La 2-X SrCuO 4 and La 2-X BaCuO 4 (where X ranges from 0.1 to 1.9). Examples of the layered perovskite represented by 3ABO 3 .A 2 B 2 O 5 include La 4 BaCu 5 O 13.4 .

Ａで示される金属としては、Ｌａ，Ｓｒ，Ｃｅ，Ｃａ，Ｙ，Ｅｒ，Ｐｒ，Ｎｄ，Ｓｍ，Ｅｕ，Ｍｇ，Ｂａ等の２価あるいは３価の金属元素が挙げられ、これらのうちの一種または二種以上の元素から選択するが、ペロブスカイト構造を形成し得る元素であれば、特にこれらに限定されるものではない。また、Ｂで示される金属は、Ｆｅ，Ｃｏ，Ｍｎ，Ｃｕ，Ｔｉ，Ｃｒ，Ｎｉ，Ｎｂ，Ｐｂ，Ｂｉ，Ｓｂ，Ｍｏ等から選ばれる一種以上の遷移金属元素及び一種以上の貴金属元素であるか、または当該一種以上の貴金属元素である。このＢサイトに含まれる貴金属元素としては、Ｐｔ，Ｒｕ，Ｐｄ，Ａｕ等があげられ、これらのうち一種または二種以上の元素から選択するが、少なくともＰｔを含むことが好ましい。このＢサイトに含まれる貴金属元素の総含有量は、Ｂサイト元素中の４〜１００％原子％ が好ましい。Ｂサイトに含まれる貴金属元素の総含有量がこれより少ないと、触媒活性が低くなる。   Examples of the metal represented by A include divalent or trivalent metal elements such as La, Sr, Ce, Ca, Y, Er, Pr, Nd, Sm, Eu, Mg, and Ba. Or it selects from 2 or more types of elements, However, If it is an element which can form a perovskite structure, it will not specifically limit to these. The metal represented by B is one or more transition metal elements and one or more noble metal elements selected from Fe, Co, Mn, Cu, Ti, Cr, Ni, Nb, Pb, Bi, Sb, Mo, and the like. Or one or more of the noble metal elements. Examples of the noble metal element contained in the B site include Pt, Ru, Pd, Au and the like, and one or more elements are selected from these, but it is preferable that at least Pt is contained. The total content of noble metal elements contained in the B site is preferably 4 to 100% atomic% in the B site element. When the total content of noble metal elements contained in the B site is less than this, the catalytic activity is lowered.

本発明の燃料電池用触媒担体は、特許文献２に記載の方法と同様の方法によって得ることができる。すなわち、ペロブスカイト型複合酸化物微粒子を構成する金属の錯イオンを含む溶液を調製し、蒸発乾固することにより、ペロブスカイト型複合酸化物の前駆体微粒子を析出させる。金属錯体としては、塩化物錯体、硝酸アミン錯体などの無機物錯体、あるいは、クエン酸錯体、リンゴ酸錯体、ピコリン酸錯体などの錯体が挙げられ、それぞれ使用する金属元素により、溶液中でイオンとして存在し得る最適なものを適宜選択すればよい。   The catalyst support for a fuel cell of the present invention can be obtained by a method similar to the method described in Patent Document 2. That is, a solution containing metal complex ions constituting the perovskite complex oxide fine particles is prepared and evaporated to dryness to precipitate the perovskite complex oxide precursor fine particles. Examples of metal complexes include inorganic complexes such as chloride complexes and amine nitrate complexes, and complexes such as citric acid complexes, malic acid complexes, and picolinic acid complexes, which exist as ions in solution depending on the metal elements used. What is necessary is just to select the optimal thing which can do suitably.

そしてさらに、このようにして得られたペロブスカイト型複合酸化物の前駆体微粒子に加熱処理を施す。こうしてペロブスカイト型複合酸化物への結晶化工程が終了する。加熱処理は、不活性ガス雰囲気中で行うことが好ましい。還元雰囲気下では、吸着された前駆体粒子がペロブスカイト型複合酸化物にならない場合があるためである。加熱処理の温度は５００〜１０００°Ｃの範囲が好ましく、５５０〜７００°Ｃの範囲がより好ましい。加熱処理温度は、ペロブスカイト型複合酸化物の結晶化温度によるため、構成元素Ａ及びＢ（貴金属元素を含む）として何を選択するかにより適宜変更する。例えばＡ＝Ｌａ，Ｂ＝Ｆｅ及びＰｔの場合、５００°Ｃ以下ではペロブスカイト型構造が形成されず、１０００°Ｃ以上という高温では焼結し、ナノサイズのペロブスカイト型複合酸化物粒子を保持するのが難しい。このような意味で、それぞれの組成において、結晶化する最低温度で熱処理することが最も好ましい。   Further, the perovskite complex oxide precursor fine particles thus obtained are subjected to a heat treatment. Thus, the crystallization step into the perovskite complex oxide is completed. The heat treatment is preferably performed in an inert gas atmosphere. This is because, in a reducing atmosphere, the adsorbed precursor particles may not become a perovskite complex oxide. The temperature of the heat treatment is preferably in the range of 500 to 1000 ° C, more preferably in the range of 550 to 700 ° C. Since the heat treatment temperature depends on the crystallization temperature of the perovskite complex oxide, it is appropriately changed depending on what is selected as the constituent elements A and B (including noble metal elements). For example, in the case of A = La, B = Fe and Pt, the perovskite structure is not formed at 500 ° C. or lower, and sintered at a high temperature of 1000 ° C. or higher to hold nano-sized perovskite complex oxide particles. Is difficult. In this sense, it is most preferable to perform heat treatment at the lowest temperature for crystallization in each composition.

＜燃料電池用触媒＞
本発明に係る燃料電池用触媒担体にＰｔ等の貴金属主触媒を担持させることにより、本発明の燃料電池触媒となる。主触媒を担持させる方法としては、従来のカーボン粒子に担持させる方法と同様の公知の方法によって行なうことができる。例えば、含浸法、溶液還元（液相還元担持）法、蒸発乾固法、コロイド吸着法、噴霧熱分解法、逆ミセル（マイクロエマルジョン法）などである。溶液還元法を例として挙げれば次のようになる。すなわち、上記ペロブスカイト型複合酸化物粒子からなる燃料電池用触媒担体に、還元剤及び触媒粒子の前駆体溶液を加え、所定時間、好ましくは３０〜１２０分間、２５〜５０℃で攪拌・混合した後、超音波ホモジナイザーなどを使用してさらに所定時間、好ましくは１０〜３０分間、２５〜５０℃で良好に分散・混合し、均一な分散液を得た後、分散液を所定時間、好ましくは１〜１２時間、６０〜９５℃で還元処理して、導電性材料上に触媒粒子を担持させる。 <Catalyst for fuel cell>
By supporting a noble metal main catalyst such as Pt on the fuel cell catalyst carrier according to the present invention, the fuel cell catalyst of the present invention is obtained. The main catalyst can be supported by a known method similar to the conventional method of supporting carbon particles. For example, impregnation method, solution reduction (liquid phase reduction support) method, evaporation to dryness method, colloid adsorption method, spray pyrolysis method, reverse micelle (microemulsion method) and the like. An example of the solution reduction method is as follows. That is, after adding the reducing agent and the catalyst particle precursor solution to the fuel cell catalyst carrier comprising the perovskite complex oxide particles, and stirring and mixing at 25 to 50 ° C. for a predetermined time, preferably 30 to 120 minutes. Further, using an ultrasonic homogenizer or the like, it is further dispersed and mixed for a predetermined time, preferably 10 to 30 minutes, at 25 to 50 ° C. to obtain a uniform dispersion, and then the dispersion is used for a predetermined time, preferably 1 Reduction treatment is performed at 60 to 95 ° C. for ˜12 hours to carry catalyst particles on the conductive material.

上記方法において、還元剤としては、エタノール、メタノール、プロパノール、ギ酸、ギ酸ナトリウムやギ酸カリウムなどのギ酸塩、ホルムアルデヒド、チオ硫酸ナトリウム、クエン酸、水素化ホウ素ナトリウム（ＮａＢＨ４）及びヒドラジン（Ｎ２Ｈ４）などが使用でき、好ましくは、エタノール、メタノール、プロパノール、ギ酸、ホルムアルデヒド、チオ硫酸ナトリウム、クエン酸、水素化ホウ素ナトリウム及びヒドラジンが使用できる。この際、還元剤の添加量は、下記に詳述する触媒粒子の前駆体を十分還元して導電性材料上に担持できる量であれば特に制限されないが、例えば、担持する触媒金属のモル数に対し、１〜２００倍モルの還元剤を投入することが好ましい。 In the above method, as the reducing agent, ethanol, methanol, propanol, formic acid, formate such as sodium formate and potassium formate, formaldehyde, sodium thiosulfate, citric acid, sodium borohydride (NaBH 4 ) and hydrazine (N 2 H 4 ) and the like can be used, and ethanol, methanol, propanol, formic acid, formaldehyde, sodium thiosulfate, citric acid, sodium borohydride and hydrazine can be preferably used. At this time, the amount of the reducing agent added is not particularly limited as long as it is an amount capable of sufficiently reducing the catalyst particle precursor described in detail below and supporting it on the conductive material. In contrast, it is preferable to add 1 to 200 moles of the reducing agent.

また、触媒粒子の前駆体としては、前記した触媒粒子に使用する金属の種類によって適宜選択できる。例えば、触媒粒子に貴金属粒子を使用する場合には、貴金属イオン源としては、例えば、硝酸ロジウム、硝酸パラジウム等の硝酸塩、塩化白金酸、ジニトロジアンミン白金等の硝酸塩、硫酸塩、アンモニウム塩、アミン、テトラアンミン白金、ヘキサアンミン白金等のアンミン塩、炭酸塩、重炭酸塩、塩化白金、塩化パラジウム等の臭化物、塩化物などのハロゲン化物、亜硝酸塩、蓚酸などの無機塩類、ギ酸塩などのカルボン酸塩および水酸化物、アルコキサイド、酸化物などの、水溶液中で貴金属イオンになれる化合物が好ましく挙げられる。これらのうち、貴金属の塩化白金酸やジニトロジアンミン白金の硝酸塩などが好ましく使用される。また、触媒粒子に遷移金属粒子を使用する場合には、例えば、上記遷移金属の硝酸塩、ジニトロジアンミン塩、硫酸塩、アンモニウム塩、アミン、炭酸塩、重炭酸塩、臭化物、塩化物などのハロゲン化物、亜硝酸塩、蓚酸などの無機塩類、ギ酸塩などのカルボン酸塩および水酸化物、アルコキサイド、酸化物などの、水溶液中で遷移金属イオンになれる化合物が好ましく挙げられる。これらのうち、遷移金属のハロゲン化物、特に塩化物、硝酸塩、及びジニトロジアンミン塩が好ましく使用され、硝酸塩が特に好ましい。なお、上記触媒粒子の前駆体は、単独であってもあるいは２種以上の混合物であってもよい。   Further, the precursor of the catalyst particles can be appropriately selected depending on the type of metal used for the catalyst particles. For example, when noble metal particles are used as catalyst particles, examples of the noble metal ion source include nitrates such as rhodium nitrate and palladium nitrate, nitrates such as chloroplatinic acid and dinitrodiammine platinum, sulfates, ammonium salts, amines, Ammine salts such as tetraammine platinum and hexaammine platinum, bromides such as carbonate, bicarbonate, platinum chloride and palladium chloride, halides such as chloride, inorganic salts such as nitrite and oxalic acid, carboxylates such as formate And compounds capable of forming noble metal ions in an aqueous solution, such as hydroxides, alkoxides and oxides, are preferred. Of these, noble metals such as chloroplatinic acid and nitrate of dinitrodiammine platinum are preferably used. When transition metal particles are used as catalyst particles, for example, halides such as nitrates, dinitrodiammine salts, sulfates, ammonium salts, amines, carbonates, bicarbonates, bromides, chlorides of the above transition metals. Inorganic salts such as nitrite and succinic acid, carboxylates such as formate and hydroxides, alkoxides, oxides and the like, which can be transition metal ions in an aqueous solution, are preferably mentioned. Of these, transition metal halides, particularly chlorides, nitrates, and dinitrodiammine salts are preferably used, and nitrates are particularly preferred. In addition, the precursor of the said catalyst particle may be individual, or 2 or more types of mixtures may be sufficient as it.

次に、上記燃料電池用触媒を用いた燃料電池用の膜電極接合体（ＭＥＡ）について説明する。   Next, a fuel cell membrane electrode assembly (MEA) using the fuel cell catalyst will be described.

図１に、燃料電池用の膜電極接合体（ＭＥＡ）の模式断面図を示す。この膜電極接合体１０は、固体高分子電解質膜１１の一面側に配置された空気極側触媒層１２と、他面側に配置された燃料極側触媒層１３とを備えており、さらにそれらの外側に空気極側ガス拡散層１４と、燃料極側ガス拡散層１５とを備えている。ガス拡散層１４、１５としては、多孔質のカーボンクロスやカーボンシートなどを用いることができる。この膜電極接合体１０は、以下に示すような一般的な方法で製造することができる。   FIG. 1 is a schematic cross-sectional view of a membrane electrode assembly (MEA) for a fuel cell. The membrane electrode assembly 10 includes an air electrode side catalyst layer 12 disposed on one surface side of the solid polymer electrolyte membrane 11, and a fuel electrode side catalyst layer 13 disposed on the other surface side, and further The air electrode side gas diffusion layer 14 and the fuel electrode side gas diffusion layer 15 are provided outside. As the gas diffusion layers 14 and 15, porous carbon cloth or carbon sheet can be used. The membrane electrode assembly 10 can be manufactured by a general method as described below.

エタノール、プロパノールなどの低級アルコールを主成分とする溶媒に、触媒担持カーボン粒子、高分子電解質溶液などを混合し、マグネチックスターラー、ボールミル、超音波分散機などの一般的な分散器具を用いて分散させて、触媒ペーストを作製する。次に、得られた触媒ペーストを、空気極用ガス拡散層及び燃料極用ガス拡散層にそれぞれ塗布し、乾燥させて、空気極及び燃料極を形成する。この際、塗布方法は、スプレー塗布やスクリーン印刷などの方法がとられる。次に、これらの電極膜が形成されたガス拡散層で、固体高分子電解質膜を挟み、ホットプレスして一体化させ、膜電極接合体を作製する。   Catalyst-supported carbon particles, polymer electrolyte solution, etc. are mixed in a solvent mainly composed of lower alcohol such as ethanol and propanol, and dispersed using a general dispersing device such as a magnetic stirrer, ball mill, or ultrasonic disperser. To prepare a catalyst paste. Next, the obtained catalyst paste is applied to the air electrode gas diffusion layer and the fuel electrode gas diffusion layer, respectively, and dried to form the air electrode and the fuel electrode. At this time, the application method is a spray application method or a screen printing method. Next, the polymer electrolyte membrane is sandwiched between the gas diffusion layers on which these electrode membranes are formed and integrated by hot pressing to produce a membrane electrode assembly.

以上のようにして得られた図１に示すごとき膜電極接合体１０において、空気極側触媒層２及び燃料極側触媒層３のそれぞれに図示しない集電板を設けて電気的な接続を行い、空気極側触媒層２に空気（酸素）燃料極側触媒層３に水素を、をそれぞれ供給することにより、燃料電池とすることができる。   In the membrane electrode assembly 10 as shown in FIG. 1 obtained as described above, a current collector plate (not shown) is provided on each of the air electrode side catalyst layer 2 and the fuel electrode side catalyst layer 3 for electrical connection. By supplying hydrogen to the air electrode side catalyst layer 2 and hydrogen to the air (oxygen) fuel electrode side catalyst layer 3, a fuel cell can be obtained.

以下、本発明を具体化した実施例について詳細に説明する。   Hereinafter, embodiments embodying the present invention will be described in detail.

−層状ペロブスカイト型複合金属酸化物からなる触媒担体の合成−
層状ペロブスカイト型複合金属酸化物からなる触媒担体は特許文献２の実施例に記載の方法と同様の方法で合成することができる。
＜LaFeO3からなる触媒担体の製造＞
（錯イオン調製工程）
塩化ランタン七水和物3.７１ｇ及び塩化鉄六水和物2.５７ｇを水１００ｍｌに溶解し、ランタンイオン及び鉄イオンに対して当量のクエン酸を加え、ランタン及び鉄のクエン酸錯イオンを含む水溶液を調整する。 -Synthesis of catalyst support composed of layered perovskite complex metal oxide-
A catalyst carrier comprising a layered perovskite complex metal oxide can be synthesized by a method similar to the method described in the Examples of Patent Document 2.
<Manufacture of catalyst support made of LaFeO 3 >
(Complex ion preparation process)
Dissolve 3.71 g of lanthanum chloride heptahydrate and 2.57 g of iron chloride hexahydrate in 100 ml of water, add an equivalent amount of citric acid to lanthanum ion and iron ion, and add citrate complex ion of lanthanum and iron. Prepare the aqueous solution.

（結晶化工程）
こうして得た、ランタン及び鉄のクエン酸錯イオンを含む水溶液を、９０°Ｃで乾燥させ、さらに、これを窒素中６００°Ｃで加熱処理し、LaFeO3粒子からなる触媒担体を得る。 (Crystallization process)
The aqueous solution containing lanthanum and iron citrate complex ions thus obtained is dried at 90 ° C., and further heat-treated at 600 ° C. in nitrogen to obtain a catalyst support composed of LaFeO 3 particles.

−燃料電池用触媒の製造−
上記のようにして得たLaFeO3粒子からなる触媒担体へのＰｔ等の貴金属からなる主触媒の担持方法は、カーボン粒子への担持方法と同様に行なうことができる。すなわち、塩化白金酸六水和物0.２６ｇをエタノール５０ｍｌに溶解し、白金イオンを含むエタノール溶液を調製する。このエタノール溶液を、先に得られたLaFeO3粒子からなる触媒担体に含浸させ、６０°Ｃで乾燥させる。こうして、Ｐｔ担持LaFeO3を得る。 -Manufacture of fuel cell catalysts-
The method for supporting the main catalyst made of a noble metal such as Pt on the catalyst support made of LaFeO 3 particles obtained as described above can be performed in the same manner as the method for supporting the carbon particles. That is, 0.26 g of chloroplatinic acid hexahydrate is dissolved in 50 ml of ethanol to prepare an ethanol solution containing platinum ions. This ethanol solution is impregnated into the catalyst support made of LaFeO 3 particles obtained earlier and dried at 60 ° C. Thus, Pt-supported LaFeO 3 is obtained.

−電極作製用ペーストの製造−
上記のようにして得られたＰｔ担持LaFeO3に、ナフィオン（登録商標）をイソプロピルアルコールに溶かした５質量％溶液を加え公転式遠心攪拌機を行い、電極作製用ペーストを得ることができる。 -Production of electrode paste-
A 5 mass% solution of Nafion (registered trademark) dissolved in isopropyl alcohol is added to the Pt-supported LaFeO 3 obtained as described above, and a revolving centrifugal stirrer is performed to obtain a paste for electrode preparation.

−燃料電池単層セルの製造−
上記電極作製用ペーストを用いて燃料電池単層セルを作製することができる。すなわち、まず電極作製用ペーストをカーボンクロスの表面にＰｔ担持量が０．４ｍｇ／ｃｍ２となるように印刷して、乾燥して拡散層を得る。なお、拡散層の上に印刷して触媒層を形成する替わりに、ポリテトラフルオロエチレン製のシート上に上記電極作製用ペーストで印刷し、乾燥後、剥離させて自立した触媒層膜を作製し、これを拡散層と熱圧着させて触媒層を形成してもよい。 -Manufacture of fuel cell single layer cells-
A fuel cell single-layer cell can be produced using the above electrode production paste. That is, first, the electrode preparation paste is printed on the surface of the carbon cloth so that the amount of Pt supported is 0.4 mg / cm 2 and dried to obtain a diffusion layer. Instead of printing on the diffusion layer and forming the catalyst layer, the electrode layer-forming paste is printed on a polytetrafluoroethylene sheet, dried and then peeled off to produce a self-supporting catalyst layer film. The catalyst layer may be formed by thermocompression bonding with the diffusion layer.

この発明は、上記発明の実施例の説明に何ら限定されるものではない。特許請求の範囲の記載を逸脱せず、当業者が容易に想到できる範囲で種々の変形態様もこの発明に含まれる。   The present invention is not limited to the description of the embodiments of the invention. Various modifications may be included in the present invention as long as those skilled in the art can easily conceive without departing from the description of the scope of claims.

１１…固体高分子電解質膜
１２…空気極側触媒層
１３…燃料極側触媒層
１４…空気極側ガス拡散層
１５…燃料極側ガス拡散層
１０…膜電極接合体 DESCRIPTION OF SYMBOLS 11 ... Solid polymer electrolyte membrane 12 ... Air electrode side catalyst layer 13 ... Fuel electrode side catalyst layer 14 ... Air electrode side gas diffusion layer 15 ... Fuel electrode side gas diffusion layer 10 ... Membrane electrode assembly

Claims (5)

導電性を有するペロブスカイト型複合金属酸化物微粒子からなる燃料電池用触媒担体   Catalyst support for fuel cell comprising conductive perovskite type composite metal oxide fine particles 前記ペロブスカイト型複合金属酸化物微粒子は層状ペロブスカイトからなることを特徴とする請求項１記載の燃料電池用触媒担体。   2. The fuel cell catalyst carrier according to claim 1, wherein the perovskite-type composite metal oxide fine particles are composed of layered perovskite. 前記ペロブスカイト型複合金属酸化物微粒子は一般式Ａ２ＢＯ４及び／又は３ＡＢＯ３・Ａ２Ｂ２Ｏ５で表される化合物からなることを特徴とする請求項２記載の燃料電池用触媒担体。 3. The fuel cell catalyst carrier according to claim 2, wherein the perovskite-type composite metal oxide fine particles are composed of a compound represented by the general formula A 2 BO 4 and / or 3ABO 3 .A 2 B 2 O 5 . 請求項１乃至３のいずれか１項記載の燃料電池用触媒担体に主触媒としての金属が担持されていることを特徴とする燃料電池用触媒。   A fuel cell catalyst, wherein a metal as a main catalyst is supported on the fuel cell catalyst carrier according to any one of claims 1 to 3. 請求項４に記載の燃料電池用触媒を用いてなる燃料電池用電極。   A fuel cell electrode comprising the fuel cell catalyst according to claim 4.
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2012104273A (en) * 2010-11-08 2012-05-31 Hitachi Zosen Corp Metal-air battery
JP2012164610A (en) * 2011-02-09 2012-08-30 Toyota Motor Corp Solid electrolyte containing layered metal oxide, and method for manufacturing the same
JP2012164609A (en) * 2011-02-09 2012-08-30 Toyota Motor Corp Electrode containing layered metal oxide, and fuel cell comprising solid electrolyte layer
US8986894B2 (en) 2011-02-09 2015-03-24 Toyota Jidosha Kabushiki Kaisha Solid electrolyte including layered metal oxide, fuel cell including thereof, production method for solid electrolyte, and production method for electrode catalyst

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04298240A (en) * 1991-03-27 1992-10-22 Tokuyama Soda Co Ltd Composition for electrode
JPH0773886A (en) * 1993-09-03 1995-03-17 Nippon Telegr & Teleph Corp <Ntt> Solid electrolyte type fuel cell
JPH07161360A (en) * 1993-12-07 1995-06-23 Nippon Telegr & Teleph Corp <Ntt> Air electrode material for low temperature action type solid fuel cell
JP2005050760A (en) * 2003-07-31 2005-02-24 Seimi Chem Co Ltd Anode electrode catalyst for solid polymer electrolytic fuel cell
JP2005166397A (en) * 2003-12-02 2005-06-23 Central Res Inst Of Electric Power Ind Oxygen ion conductor using stratiform cobalt oxide, and fuel cell using it
JP2006236778A (en) * 2005-02-24 2006-09-07 Toyota Motor Corp Catalyst for fuel cell, membrane electrode complex, and solid polymer electrolyte fuel cell
JP2006260844A (en) * 2005-03-15 2006-09-28 Toshiba Corp Catalyst for fuel cell electrode, fuel cell electrode, membrane electrode assembly, and fuel cell
JP2007012284A (en) * 2005-06-28 2007-01-18 Toshiba Corp Electrode catalyst, manufacturing method thereof, fuel electrode, and fuel cell apparatus
WO2007145215A1 (en) * 2006-06-13 2007-12-21 Hitachi Maxell, Ltd. Carbon particle having deposited fine particles, process for producing the same, and electrode for fuel cell

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04298240A (en) * 1991-03-27 1992-10-22 Tokuyama Soda Co Ltd Composition for electrode
JPH0773886A (en) * 1993-09-03 1995-03-17 Nippon Telegr & Teleph Corp <Ntt> Solid electrolyte type fuel cell
JPH07161360A (en) * 1993-12-07 1995-06-23 Nippon Telegr & Teleph Corp <Ntt> Air electrode material for low temperature action type solid fuel cell
JP2005050760A (en) * 2003-07-31 2005-02-24 Seimi Chem Co Ltd Anode electrode catalyst for solid polymer electrolytic fuel cell
JP2005166397A (en) * 2003-12-02 2005-06-23 Central Res Inst Of Electric Power Ind Oxygen ion conductor using stratiform cobalt oxide, and fuel cell using it
JP2006236778A (en) * 2005-02-24 2006-09-07 Toyota Motor Corp Catalyst for fuel cell, membrane electrode complex, and solid polymer electrolyte fuel cell
JP2006260844A (en) * 2005-03-15 2006-09-28 Toshiba Corp Catalyst for fuel cell electrode, fuel cell electrode, membrane electrode assembly, and fuel cell
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WO2007145215A1 (en) * 2006-06-13 2007-12-21 Hitachi Maxell, Ltd. Carbon particle having deposited fine particles, process for producing the same, and electrode for fuel cell

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