JPH09302438A - Nickel/ysz cermet and its manufacture - Google Patents
Nickel/ysz cermet and its manufactureInfo
- Publication number
- JPH09302438A JPH09302438A JP8143427A JP14342796A JPH09302438A JP H09302438 A JPH09302438 A JP H09302438A JP 8143427 A JP8143427 A JP 8143427A JP 14342796 A JP14342796 A JP 14342796A JP H09302438 A JPH09302438 A JP H09302438A
- Authority
- JP
- Japan
- Prior art keywords
- ysz
- calcination
- cermet
- powder
- nio
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- 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
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/50—Fuel cells
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、固体電解質型燃料
電池の燃料電極材料として好適なＮｉ／ＹＳＺサーメッ
ト及びその製造方法に関する。特には、長時間高温にさ
らされた場合にもＮｉの凝集がほとんど生じることがな
く、燃料電極のクラックや剥離及び電気抵抗の増大とい
ったＮｉ凝集に起因する燃料電極の特性劣化を防止する
ことのできるＮｉ／ＹＳＺサーメットに関する。TECHNICAL FIELD The present invention relates to a Ni / YSZ cermet suitable as a fuel electrode material for a solid oxide fuel cell and a method for producing the same. In particular, even when exposed to a high temperature for a long time, Ni agglomeration hardly occurs, and it is possible to prevent characteristic deterioration of the fuel electrode due to Ni agglomeration such as cracking or peeling of the fuel electrode and increase in electric resistance. Regarding Ni / YSZ cermet which can be made.
【０００２】[0002]
【従来の技術】円筒型セルタイプの固体電解質型燃料電
池（以下Ｔ−ＳＯＦＣとも言う）の燃料電極を例にとっ
て従来技術を説明する。Ｔ−ＳＯＦＣは、特公平１−５
９７０５等に開示されている固体電解質型燃料電池（以
下ＳＯＦＣとも言う）の一タイプである。Ｔ−ＳＯＦＣ
は、多孔質支持管−空気電極−固体電解質−燃料電極−
インターコネクターで構成される円筒型セルを有する。
空気電極側に酸素（空気）を流し、燃料電極側にガス燃
料（Ｈ2 、ＣＯ等）を流してやると、このセル内でＯ2-
イオンが移動して化学的燃焼が起り、空気電極と燃料電
極の間に電位が生じ発電が行われる。なお、空気電極が
支持管を兼用する形式のものもある。Ｔ−ＳＯＦＣの実
証試験は、１９９３年段階で２５kw級のもの（セル有効
長５０cm、セル数１１５２本) までが進行中である。2. Description of the Related Art The prior art will be described by taking a fuel electrode of a cylindrical cell type solid oxide fuel cell (hereinafter also referred to as T-SOFC) as an example. T-SOFC is 1-5
It is a type of solid oxide fuel cell (hereinafter also referred to as SOFC) disclosed in 9705 and the like. T-SOFC
Is a porous support tube-air electrode-solid electrolyte-fuel electrode-
It has a cylindrical cell composed of interconnectors.
When oxygen (air) is flown to the air electrode side and gas fuel (H 2 , CO, etc.) is flown to the fuel electrode side, O 2-
Ions move to cause chemical combustion, and an electric potential is generated between the air electrode and the fuel electrode to generate electricity. There is also a type in which the air electrode also serves as the support tube. Demonstration tests of T-SOFCs are in progress up to the 25 kW class (cell effective length 50 cm, 1152 cells) as of 1993.
【０００３】現状の代表的なＴ−ＳＯＦＣの構成材料、
厚さ及び製造方法は以下のとおりである（Proc. of the
3rd Int. Symp. on SOFC, 1993 ）。 支持管：ＺｒＯ2 （ＣａＯ）、厚さ１．２mm、押し出し 空気電極：Ｌａ（Ｓｒ）ＭｎＯ3 、厚さ１．４mm、スラ
リーコート 固体電解質：ＺｒＯ2 （Ｙ2 Ｏ3 ）、厚さ４０μm 、Ｅ
ＶＤ インターコネクター：ＬａＣｒ（Ｍｇ）Ｏ3 、厚さ４０
μm 、ＥＶＤ 燃料電極：Ｎｉ−ＺｒＯ2 （Ｙ2 Ｏ3 ）、厚さ１００μ
m 、スラリーコート−ＥＶＤ[0003] At present, typical constituent materials of T-SOFC,
The thickness and manufacturing method are as follows (Proc. Of the
3rd Int. Symp. On SOFC, 1993). Support tube: ZrO 2 (CaO), thickness 1.2 mm, extrusion Air electrode: La (Sr) MnO 3 , thickness 1.4 mm, slurry coat Solid electrolyte: ZrO 2 (Y 2 O 3 ), thickness 40 μm, E
VD interconnector: LaCr (Mg) O 3 , thickness 40
μm, EVD fuel electrode: Ni-ZrO 2 (Y 2 O 3 ), thickness 100 μm
m, slurry coat-EVD
【０００４】上述の代表的な燃料電極材料であるＮｉ−
ＺｒＯ2 （Ｙ2 Ｏ3 ）（Ｎｉ／ＹＳＺサーメット）は、
各成分（ＮｉとＹＳＺ）が交錯した微構造を有するが、
Ｎｉが網目のようにつながっているものは導電性が良
く、ＮｉやＹＳＺ粒の凝集が生じて、Ｎｉの網目が切断
されているものは導電性が悪い。ＳＯＦＣの燃料電極の
導電性が悪いとＳＯＦＣの発電効率は低下する。したが
って、ＮｉやＹＳＺの凝集がなく、Ｎｉの網目構造がし
っかりと形成されうるようなＮｉ／ＹＳＺサーメットが
求められる。さらに、ＮｉはＳＯＦＣの運転中にも焼結
凝集を起こそうとするので、Ｎｉの網目は細く均一でな
ければならないという要請もある。なおＮｉが凝集する
と、Ｎｉ、固体電解質、気相（燃料ガス）の三相界面が
減少して酸素イオンと燃料ガスとの反応が低下するとい
う不利も伴う。Ni- which is a typical fuel electrode material described above
ZrO 2 (Y 2 O 3 ) (Ni / YSZ cermet) is
It has a microstructure in which each component (Ni and YSZ) intersects,
When Ni is connected like a mesh, the conductivity is good, and when Ni or YSZ particles are aggregated and the Ni mesh is cut, the conductivity is poor. If the conductivity of the SOFC fuel electrode is poor, the power generation efficiency of the SOFC decreases. Therefore, there is a demand for a Ni / YSZ cermet in which Ni and YSZ are not aggregated and a Ni network structure can be firmly formed. Further, since Ni tends to cause sinter aggregation even during the operation of SOFC, there is also a demand that the Ni mesh should be fine and uniform. Note that when Ni is aggregated, the three-phase interface of Ni, the solid electrolyte, and the gas phase (fuel gas) decreases, and the reaction between oxygen ions and the fuel gas decreases, which is also disadvantageous.
【０００５】このようなＮｉ／ＹＳＺサーメットの微構
造に関しては、次のような２つの提案がなされている。 特開平４−１３３２６４：このＮｉ／ＹＳＺサーメット
の構造では、Ｎｉが多孔質骨格として存在し、そのＮｉ
の骨格がＹＳＺ薄膜によって覆われており、さらにＮｉ
骨格とＹＳＺ薄膜との間に間隙が存在する。その製造方
法は、まずＮｉＯの多孔質膜を固体電解質層上に形成
（実施例はスクリーン印刷）しておいて、このＮｉＯ多
孔質膜にＹＳＺの前駆液を含浸させ、その後熱分解によ
りＹＳＺをＮｉＯ骨格上に生成させ、さらにその後に還
元処理によりＮｉＯをＮｉに還元し、この時にＮｉＯ骨
格の体積収縮によりＮｉ骨格とＹＳＺ薄膜の間に間隙を
形成するというものである。Regarding the microstructure of such Ni / YSZ cermet, the following two proposals have been made. JP-A-4-133264: In this structure of Ni / YSZ cermet, Ni exists as a porous skeleton, and
The skeleton of is covered with YSZ thin film.
There is a gap between the skeleton and the YSZ thin film. The manufacturing method is as follows. First, a NiO porous film is formed on the solid electrolyte layer (screen printing in the example), the NiO porous film is impregnated with a precursor solution of YSZ, and then YSZ is decomposed by thermal decomposition. It is formed on the NiO skeleton, and then NiO is reduced to Ni by a reduction treatment, and at this time, a volume is contracted of the NiO skeleton to form a gap between the Ni skeleton and the YSZ thin film.
【０００６】特開平４−１９２２６１：このＮｉ／ＹＳ
Ｚサーメットの構造は、Ｎｉの多孔質骨格が存在し、こ
の骨格の表面に接してＹＳＺ粒子が散在している、とい
うものである。その製造方法は、平均粒径２μm のＮｉ
Ｏ粉末と平均粒径０．３μm のＹＳＺ粉末をペースト化
し、スクリーン印刷により固体電解質上に燃料電極膜を
形成し、その後１，２００℃焼成、１，０００℃還元処
理を行うというものである。JP-A-4-192261: This Ni / YS
The structure of Z cermet is such that a porous Ni skeleton is present and YSZ particles are scattered in contact with the surface of this skeleton. The manufacturing method is Ni with an average particle size of 2 μm.
O powder and YSZ powder having an average particle size of 0.3 μm are made into a paste, a fuel electrode film is formed on the solid electrolyte by screen printing, and thereafter, 1200 ° C. firing and 1,000 ° C. reduction treatment are performed.
【０００７】[0007]
【発明が解決しようとする課題】上記特開平４−１３３
２６４号の技術には次のような問題点がある。 ＮｉＯ骨格の表面をＹＳＺで覆いきってしまうと、
ＮｉＯの還元が不可能となり、また集電抵抗を下げるた
めに燃料電極表面を機械的に研削するなどの後処理が必
要となる。 ＹＳＺ前駆液の含浸・熱分解の回数がきわめて多い
（実施例１５回）。DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
The H.264 technology has the following problems. If you cover the surface of the NiO skeleton with YSZ,
NiO cannot be reduced, and post-treatment such as mechanically grinding the surface of the fuel electrode is required to reduce the current collecting resistance. The number of times of impregnation / pyrolysis of the YSZ precursor solution is extremely large (Example 15 times).
【０００８】上記特開平４−１９２２６１号の技術には
次のような問題点がある。 ＹＳＺ粉がＮｉ骨格上に散在する程度ではＮｉの焼
結・凝集を抑制する効果は小さく耐久性に劣る燃料電極
となる。 上記と同じ。本発明は、長時間高温にさらされた
場合にもＮｉの凝集がほとんど生じることがなく、ＳＯ
ＦＣの燃料電極のクラックや剥離及び電気抵抗の増大と
いった、Ｎｉ凝集に起因する燃料電極の特性劣化を防止
することのできるＮｉ／ＹＳＺサーメットを提供するこ
とを目的とする。The technique of Japanese Patent Laid-Open No. 4-192261 has the following problems. If the YSZ powder is scattered on the Ni skeleton, the effect of suppressing Ni sintering and agglomeration is small and the fuel electrode has poor durability. Same as above. According to the present invention, even when exposed to a high temperature for a long time, almost no Ni agglomeration occurs, and
An object of the present invention is to provide a Ni / YSZ cermet capable of preventing deterioration of the characteristics of the fuel electrode due to Ni agglomeration, such as cracking and peeling of the FC fuel electrode and increase in electric resistance.
【０００９】[0009]
【課題を解決するための手段】本発明者は、Ｎｉ／ＹＳ
Ｚサーメットの構成成分であるＮｉとＹＳＺの骨格が互
いに三次元的に接触していれば、Ｎｉの焼結がＹＳＺの
骨格によって抑制されるためＮｉの凝集が起こり難く、
耐久性に優れた燃料電極を製造し得るとの着想を得た。
このためには、お互いの成分粒子が均一に混合され、且
つ焼結状態が均一であるように粒径分布幅の狭い状態に
あることが必要と考え、種々の粉末合成方法を検討する
とともにそのキャラクタリゼーションを行った結果、本
発明を完成するに至った。The present inventor has found that Ni / YS
If the skeletons of Ni and YSZ, which are the constituents of the Z cermet, are three-dimensionally in contact with each other, sintering of Ni is suppressed by the skeleton of YSZ, and thus Ni agglomeration is less likely to occur.
The idea was that a fuel electrode with excellent durability could be manufactured.
For this purpose, it is necessary that the component particles of each are uniformly mixed, and that the particle size distribution width is narrow so that the sintering state is uniform, and various powder synthesis methods are studied and As a result of characterization, the present invention has been completed.
【００１０】上記課題を解決するため、本発明のＮｉ／
ＹＳＺサーメットは、ＮｉとＹＳＺ（イットリア安定化
ジルコニア）の粒子の焼結体からなるＮｉ／ＹＳＺサー
メットであって； Ｎｉ／ＹＳＺ組成比が２４／７６〜
６４／３６wt％であり、 粒子の平均粒径が２μm 以下
であり、 該サーメットを貫通する線分が横切る粒界の
数において、 （ＮｉとＹＳＺとの粒界数／全粒界数）
≧０．４、 ここで全粒界数＝ＮｉとＹＳＺとの粒界数
＋ＹＳＺとＹＳＺとの粒界数＋ＮｉとＮｉとの粒界数、
であることを特徴とする。すなわち、粒子の平均粒径
が細かいとともに、Ｎｉ粒とＹＳＺ粒がよく分散してい
る構造を有している。ここで、粒子とは基本的に一次粒
子を指し、これらの凝集した二次粒子においては、二次
粒子内に粒界が存在すると定義する。粒界は一次粒子間
の接合部界面を指し、一次粒子が結合して粒成長した様
な大きな粒子はその単体が１個の粒子であって、その粒
内に粒界は存在しないと考える。In order to solve the above problems, Ni /
The YSZ cermet is a Ni / YSZ cermet composed of a sintered body of particles of Ni and YSZ (yttria-stabilized zirconia); Ni / YSZ composition ratio is 24/76 to
64/36 wt%, the average particle size of the particles is 2 μm or less, and the number of grain boundaries crossed by the line segment penetrating the cermet is (the number of grain boundaries between Ni and YSZ / the number of all grain boundaries).
≧ 0.4, where the total number of grain boundaries = the number of grain boundaries between Ni and YSZ + the number of grain boundaries between YSZ and YSZ + the number of grain boundaries between Ni and Ni,
It is characterized by being. That is, the average particle size of the particles is small, and the Ni particles and the YSZ particles are well dispersed. Here, the particles basically refer to primary particles, and in these agglomerated secondary particles, it is defined that grain boundaries exist within the secondary particles. A grain boundary refers to a joint interface between primary particles, and it is considered that a large particle, such as primary particles that have been bonded and grown, is a single particle, and no grain boundary exists within the particle.
【００１１】また、本発明のＮｉ／ＹＳＺサーメットの
製造方法は、ＮｉとＹＳＺの粒子の焼結体からなるＮｉ
／ＹＳＺサーメットを製造する方法であって； 湿式法
により、Ｎｉ、Ｚｒ、Ｙ及び酸素を含む混合物を得る湿
式混合工程と、 該混合物を分解して上記各金属の酸化
物を含む粉粒体を得る分解工程と、 該粉粒体を仮焼す
る一次仮焼工程と、 仮焼後の粉粒体（ＮｉＯ／ＹＳＺ
複合粉末）を粉砕する粉砕工程と、 この粉砕工程で得
られた粉砕粉を再度仮焼する二次仮焼工程と、二次仮焼
したＮｉＯ／ＹＳＺ複合粉末を、スラリーコート法によ
り基体上に成膜する工程と、 このＮｉＯ／ＹＳＺ複合
粉末膜を１，２００〜１，４５０℃で焼成する工程と、
このＮｉＯ／ＹＳＺ複合粉末膜を還元する工程と、を
含むことを特徴とする。Further, the method for producing a Ni / YSZ cermet according to the present invention is a method in which Ni composed of a sintered body of Ni and YSZ particles is used.
/ YSZ cermet manufacturing method; a wet mixing step of obtaining a mixture containing Ni, Zr, Y and oxygen by a wet method, and decomposing the mixture to obtain a granular material containing an oxide of each metal. A decomposition step to obtain, a primary calcination step of calcination of the powder and granules, and a powder (NiO / YSZ) after the calcination
A pulverization step of pulverizing the composite powder), a secondary calcination step of calcination of the pulverized powder obtained in the pulverization step again, and a secondary calcination NiO / YSZ composite powder on a substrate by a slurry coating method. A step of forming a film, and a step of firing the NiO / YSZ composite powder film at 1,200 to 1,450 ° C.
And a step of reducing the NiO / YSZ composite powder film.
【００１２】[0012]
【発明の実施の形態】本発明の一態様のＮｉ／ＹＳＺサ
ーメットの製造方法は、 ＮｉとＹＳＺの粒子の焼結体
からなるＮｉ／ＹＳＺサーメットを製造する方法であっ
て； Ｎｉイオン、Ｚｒイオン、Ｙイオンを所望割合で
含む原料溶液を調整する溶液調整工程と、 共沈溶液を
上記原料溶液に混合して、上記各金属の１種以上及び酸
素を含む固体物質（共沈物質）を上記原料溶液から共沈
させる共沈工程と、 該共沈物質を分解して上記各金属
の酸化物を含む粉粒体を得る分解工程と、 該粉粒体を
仮焼する仮焼工程と、 仮焼後の粉粒体（ＮｉＯ／ＹＳ
Ｚ複合粉末）を粉砕する粉砕工程と、 この粉砕工程で
得られた粉砕粉を再度仮焼する二次仮焼工程と、二次仮
焼したＮｉＯ／ＹＳＺ複合粉末を、スラリーコート法に
より基体上に成膜する工程と、 このＮｉＯ／ＹＳＺ複
合粉末膜を１，２００〜１，４５０℃で焼成する工程
と、 このＮｉＯ／ＹＳＺ複合粉末膜を還元する工程
と、を含むことを特徴とする。なお、前述のとおり、湿
式混合工程→熱分解によりＮｉ、Ｚｒ、Ｙの酸化物を含
む粉粒体を得ることとしてもよい。BEST MODE FOR CARRYING OUT THE INVENTION A method for producing a Ni / YSZ cermet according to one aspect of the present invention is a method for producing a Ni / YSZ cermet comprising a sintered body of particles of Ni and YSZ; Ni ion, Zr ion , A solution adjusting step of adjusting a raw material solution containing Y ions in a desired ratio, and mixing the coprecipitation solution with the raw material solution to form a solid substance (coprecipitating substance) containing one or more of each metal and oxygen as described above. A coprecipitation step of coprecipitating from the raw material solution, a decomposition step of decomposing the coprecipitation substance to obtain a granular material containing the oxide of each metal, and a calcination step of calcining the granular material. Powdered material after firing (NiO / YS
Z composite powder), a secondary calcination step of calcination of the pulverized powder obtained in this pulverization step again, and a secondary calcinated NiO / YSZ composite powder on a substrate by a slurry coating method. And a step of firing the NiO / YSZ composite powder film at 1,200 to 1,450 ° C., and a step of reducing the NiO / YSZ composite powder film. Note that, as described above, it is possible to obtain a powder or granular material containing oxides of Ni, Zr, and Y by the wet mixing step → thermal decomposition.
【００１３】この態様（共沈法）のＮｉ／ＹＳＺサーメ
ットの製造方法においては、原料溶液として硝酸水溶液
をベースとする溶液を用い、共沈溶液として蓚酸水溶液
を用いることができる。この場合、以下のような共沈反
応が生じる。 Ｎｉ2+＋（ＣＯＯＨ）2 →Ｎｉ（ＣＯＯ）2 ↓＋２Ｈ+ Ｚｒ4+＋２（ＣＯＯＨ）2 →Ｚｒ（ＣＯＯ）4 ↓＋４Ｈ
+ ２Ｙ3+＋３（ＣＯＯＨ）2 →Ｙ2 （ＣＯＯ）6 ↓＋６Ｈ
+ In the method for producing a Ni / YSZ cermet according to this aspect (coprecipitation method), a solution based on a nitric acid aqueous solution can be used as a raw material solution, and an oxalic acid aqueous solution can be used as a coprecipitation solution. In this case, the following coprecipitation reaction occurs. Ni 2+ + (COOH) 2 → Ni (COO) 2 ↓ + 2H + Zr 4+ +2 (COOH) 2 → Zr (COO) 4 ↓ + 4H
+ 2Y 3+ +3 (COOH) 2 → Y 2 (COO) 6 ↓ + 6H
+
【００１４】上記態様のＮｉ／ＹＳＺサーメットの製造
方法においては、原料溶液及び共沈溶液をあらかじめ６
０℃〜沸点に昇温させてから混合することが好ましい。
上記反応のうち蓚酸Ｎｉの沈降反応は、一般的には、常
温においては生じにくい。そのため、均一な組成の共沈
物質を得にくい。それに対して、上記温度域において
は、上述の３反応がほぼ均等に起こるため、均一な組成
の共沈物質を能率よく得ることができる。In the method for producing the Ni / YSZ cermet according to the above-mentioned embodiment, the raw material solution and the coprecipitation solution are preliminarily 6
It is preferable to raise the temperature to 0 ° C. to the boiling point and then mix.
Of the above reactions, the precipitation reaction of Ni oxalate is generally unlikely to occur at room temperature. Therefore, it is difficult to obtain a coprecipitated substance having a uniform composition. On the other hand, in the above temperature range, the above-mentioned three reactions occur almost uniformly, so that a coprecipitated substance having a uniform composition can be efficiently obtained.
【００１５】本発明のＮｉ／ＹＳＺサーメットは、Ｎｉ
／ＹＳＺ組成比が２４／７６〜６４／３６wt％である。
ＹＳＺの比が７６を越えると粉末の焼成膜の導電率が低
くなる。このような観点からは、Ｎｉ／ＹＳＺ組成比
は、４５／５５〜６４／３６であることがより好まし
い。しかし、固体電解質膜と燃料電極との間の傾斜層用
としては、低Ｎｉのものが、膜そのものの導電率は小さ
いが、高Ｎｉ含有層と電解質との間の熱膨張差に起因す
る応力を緩和できるので好ましい。The Ni / YSZ cermet of the present invention is made of Ni
/ YSZ composition ratio is 24/76 to 64/36 wt%.
If the YSZ ratio exceeds 76, the conductivity of the powder fired film becomes low. From such a viewpoint, the Ni / YSZ composition ratio is more preferably 45/55 to 64/36. However, for the graded layer between the solid electrolyte membrane and the fuel electrode, a low Ni one has a low conductivity of the membrane itself, but a stress due to a difference in thermal expansion between the high Ni content layer and the electrolyte. Can be relaxed, which is preferable.
【００１６】本発明のＮｉ／ＹＳＺサーメットをＳＯＦ
Ｃの燃料電極材として用いる場合には、Ｎｉ／ＹＳＺサ
ーメット原料粉末の粒径を０．１〜１０μm とすること
が好ましい。ガス透過性と導電率とのバランスが良好だ
からである。この際、燃料電極の上層を比較的粗い粒を
用い、下層を比較的細かい粒を用いて形成することもで
きる。The Ni / YSZ cermet of the present invention is SOF
When used as a C fuel electrode material, the particle size of the Ni / YSZ cermet raw material powder is preferably 0.1 to 10 μm. This is because the balance between gas permeability and conductivity is good. At this time, the upper layer of the fuel electrode may be formed using relatively coarse particles, and the lower layer may be formed using relatively fine particles.
【００１７】本発明のＮｉ／ＹＳＺサーメットの製造方
法においては、二次仮焼した後に、所望の粒度やＢＥＴ
値が得られないときには、さらに粉砕、三次仮焼、粉
砕、四次仮焼、粉砕、五次仮焼へと進んでもよい。ただ
し、回数を繰り返しても粉砕によって微粒化されるので
粉体特性はある粒度、ＢＥＴ値に収束するので大きな変
化は現れなくなり、その処理効果は小さいものとなる。
また、工程数が増えるので製造条件上コスト高となって
くる。さらに、粉体の焼結性が劣るものとなってくるの
で成膜焼成温度を上げなければならず、ＳＯＦＣセルを
構成する他の部材の焼結をも引き起こすことで、セル特
性が変化する危険性が生じる。したがって、通常条件で
セル作製の可能な工程繰り返し数は５回以下が好まし
い。In the method for producing the Ni / YSZ cermet of the present invention, after the secondary calcination, the desired grain size and BET are obtained.
When the value cannot be obtained, further pulverization, tertiary calcination, pulverization, quaternary calcination, pulverization, and fifth calcination may be performed. However, even if the number of times is repeated, the particles are pulverized into fine particles, and the powder characteristics converge to a certain particle size and BET value, so that a large change does not appear and the treatment effect is small.
Further, since the number of steps is increased, the cost is increased due to manufacturing conditions. Furthermore, since the sinterability of the powder becomes inferior, it is necessary to raise the film formation firing temperature, and the sintering of other members constituting the SOFC cell is also caused, which may change the cell characteristics. Sexuality occurs. Therefore, it is preferable that the number of process repetitions that allows cell production under normal conditions be 5 or less.
【００１８】仮焼条件については一次仮焼の条件が（８
００〜１，２５０℃）×（２〜１０Hr）であり、二次仮
焼の条件が（７００〜１，０５０℃）×（２〜１０Hr）
が好ましい。さらには一次仮焼の仮焼条件が（９００〜
１，２００℃）×（２〜１０Hr）であり、二次仮焼の仮
焼条件が（８００〜１，０００℃）×（２〜１０Hr）が
より好ましい。その理由は、一次仮焼の際には、８００
℃以下の熱処理（仮焼）温度であると、硝酸成分が残る
可能性があって原料粉末の純度が落ちることと、熱処理
をしても焼結が進まずに微粒子のままの状態で残り、後
のＳＯＦＣ燃料電極成膜（焼成）の際に過剰に焼結して
しまうからである。また、１，２５０℃以上の仮焼では
仮焼粉が固くなるので次工程での粉砕効率が低下し、製
造工程上好ましくない。二次仮焼の際には、温度が７０
０℃以下では、粉末が殆ど焼結しないので二次仮焼の効
果が小さい。また、１，０５０℃以上であると、焼結が
進んで再び粒径の大きな粉体となり易い。したがって、
二次仮焼後の粒径がＳＯＦＣセルへの成膜に好ましい粒
度範囲に納まるように制御することが重要である。二次
仮焼の温度は一次仮焼の温度よりも低くする、つまり一
次仮焼よりも二次仮焼の条件を穏やかにすることが一般
的である。なぜならば、二次仮焼条件が高温、長時間で
あれば、一次仮焼終了粉よりも粒径の大きな粒子が生成
し、ＳＯＦＣセルへの成膜に好ましくないからである。Regarding the calcination conditions, the condition of the primary calcination is (8
0 to 1,250 ° C.) × (2 to 10 hr), and the secondary calcination condition is (700 to 1,050 ° C.) × (2 to 10 hr)
Is preferred. Furthermore, the calcination conditions for the primary calcination (900 ~
1,200 ° C.) × (2 to 10 hr), and the calcination condition of the secondary calcination is more preferably (800 to 1,000 ° C.) × (2 to 10 hr). The reason is 800 at the time of primary calcination
If the heat treatment (calcination) temperature is ℃ or less, nitric acid components may remain and the purity of the raw material powder may decrease, and even if heat treatment is performed, sintering does not proceed and remains in fine particles. This is because it is excessively sintered during the subsequent SOFC fuel electrode film formation (firing). Further, calcination at 1,250 ° C. or higher causes the calcinated powder to become hard, which reduces the pulverization efficiency in the next step, which is not preferable in the manufacturing process. During the secondary calcination, the temperature is 70
Below 0 ° C., the powder hardly sinters, so the effect of secondary calcination is small. On the other hand, when the temperature is 1,050 ° C. or higher, the sintering proceeds and the powder having a large particle size is likely to be formed again. Therefore,
It is important to control the particle size after the secondary calcination so that it falls within a particle size range suitable for film formation on an SOFC cell. It is general that the temperature of the secondary calcination is lower than that of the primary calcination, that is, the condition of the secondary calcination is milder than that of the primary calcination. This is because if the secondary calcination conditions are high temperature and long time, particles having a larger particle size than the primary calcination finished powder are generated, which is not preferable for film formation on the SOFC cell.
【００１９】また、本発明のＮｉ／ＹＳＺサーメットを
ＳＯＦＣの燃料電極材として用いる場合には、原料粉末
の一次仮焼後の粉砕時に粒径を２μm 以下とすることが
好ましい。このとき、粉砕粒径が大きいと次工程の二次
仮焼にてより大きな粒子が生成し、ＳＯＦＣセルへの成
膜材料として好ましくない。仮焼後あるいは粉砕後に必
要に応じて分級を行ってもよい。When the Ni / YSZ cermet of the present invention is used as a fuel electrode material for SOFC, it is preferable that the particle size of the raw material powder is 2 μm or less during pulverization after primary calcination. At this time, if the pulverized particle size is large, larger particles are generated in the secondary calcination in the next step, which is not preferable as a film forming material for the SOFC cell. After calcination or crushing, classification may be carried out if necessary.
【００２０】[0020]
（１）原料粉末作製：共沈法、粉末混合法、蒸発乾固法
の３方法により原料粉末を作製した。 （１．１）共沈法 (1.1.1) 原料溶液調整：ＹＳＺ原料としての硝酸ジルコ
ニウム・イットリウム水溶液（８mol%Ｙ2 Ｏ3含有、酸
化物換算含有量２３．４wt% ）、ＮｉＯ原料としての硝
酸ニッケル６水和物結晶、共沈物質濃度を調整するため
の純水をＮｉＯ／ＹＳＺ組成が７０／３０wt% となるよ
うに混合し、よく攪拌した。(1) Preparation of raw material powder: A raw material powder was prepared by three methods: a coprecipitation method, a powder mixing method, and an evaporation-drying method. (1.1) Coprecipitation method (1.1.1) Preparation of raw material solution: zirconium nitrate-yttrium aqueous solution (containing 8 mol% Y 2 O 3 , oxide conversion content 23.4 wt%) as a YSZ raw material, and as a NiO raw material Nickel nitrate hexahydrate crystals and pure water for adjusting the concentration of the coprecipitated substance were mixed so that the composition of NiO / YSZ was 70/30 wt% and stirred well.
【００２１】(1.1.2) 共沈溶液調整：本実施例において
は、共沈溶液として蓚酸水溶液を用いた。容器に純水を
取り、約８０℃程度に加熱する。この温水を攪拌しなが
ら蓚酸２水和物結晶を徐々に添加して溶解し、８０℃〜
９０℃に保持した。蓚酸水溶液の量については、共沈工
程において金属イオンが完全に沈殿するように、蓚酸量
を化学量論比よりもわずかに過剰となるようすることが
好ましい。今回の過剰量は約５mol%とした。(1.1.2) Preparation of Coprecipitation Solution: In this example, an oxalic acid aqueous solution was used as the coprecipitation solution. Pure water is taken into the container and heated to about 80 ° C. While stirring this warm water, oxalic acid dihydrate crystals were gradually added and dissolved,
Hold at 90 ° C. Regarding the amount of the oxalic acid aqueous solution, it is preferable that the amount of oxalic acid is slightly in excess of the stoichiometric ratio so that the metal ions are completely precipitated in the coprecipitation step. The excess amount this time was about 5 mol%.
【００２２】(1.1.3) 溶液混合→共沈：原料溶液（Ｎｉ
Ｏ／ＹＳＺ複合粉末水溶液）を８０℃〜９０℃に加熱
し、これを８０℃〜９０℃に加熱保持した硝酸水溶液中
に、よく攪拌しながら徐々に添加していくことで、蓚酸
共沈法による沈殿生成を行った。反応により、粉体が生
成するので、溶液の攪拌にはトルクのある攪拌機を使用
することが好ましい。この共沈反応により溶液は発熱反
応を起こすので、反応後は溶液温度が初期状態よりも１
０〜２０℃程度上昇することが普通である。全溶液を混
合し終えた後、室温まで攪拌を継続しながら自然冷却し
た。(1.1.3) Solution mixing → coprecipitation: Raw material solution (Ni
(O / YSZ composite powder aqueous solution) is heated to 80 ° C. to 90 ° C. and gradually added to an aqueous nitric acid solution heated and maintained at 80 ° C. to 90 ° C. with good stirring, whereby the oxalic acid coprecipitation method is performed. The precipitation was generated by. Since powder is produced by the reaction, it is preferable to use a stirrer having a torque for stirring the solution. Since the solution causes an exothermic reaction due to this coprecipitation reaction, the temperature of the solution after the reaction is less than that of the initial state.
It is common that the temperature rises by 0 to 20 ° C. After all the solutions were mixed, the solution was naturally cooled while continuing to stir to room temperature.
【００２３】(1.1.4) 乾燥：乾燥機内に反応物を静置
し、１２０℃の熱風を送り沈殿物の水分を蒸発させた。 (1.1.5) 熱分解：乾燥後の試料は５００℃、５時間の熱
処理により、硝酸成分と残留蓚酸を除去した。その際の
反応は以下と推定される。 ２Ｎｉ（ＣＯＯ)2＋Ｏ2 →２ＮｉＯ＋４ＣＯ2 Ｚｒ（ＣＯＯ)4＋Ｏ2 →ＺｒＯ2 ＋４ＣＯ2 ２Ｙ2(ＣＯＯ)6＋３Ｏ2 →２Ｙ2 Ｏ3 ＋１２ＣＯ2 (1.1.4) Drying: The reaction product was allowed to stand in a dryer, and hot air at 120 ° C. was sent to evaporate the water content of the precipitate. (1.1.5) Pyrolysis: The dried sample was heat-treated at 500 ° C. for 5 hours to remove nitric acid components and residual oxalic acid. The reaction at that time is estimated as follows. 2Ni (COO) 2 + O 2 → 2NiO + 4CO 2 Zr (COO) 4 + O 2 → ZrO 2 + 4CO 2 2Y 2 (COO) 6 + 3O 2 → 2Y 2 O 3 + 12CO 2
【００２４】(1.1.6) 粉砕（解砕）：２φと３φのＰＳ
Ｚボールを用いた湿式粉砕処理を行った。これは、二次
粒子の紛砕と均一化を目的とする。ただし、本共沈法に
よる粉末は、湿式レーザー回折粒度分布測定によれば、
１μm 以下の粒子が全体の約８０％を占め、二次粒子の
大きなものでさえその粒径は１０〜２０μm にあること
から、このボールミル粉砕処理を省略することも可能で
ある。(1.1.6) Crushing (crushing): PS of 2φ and 3φ
A wet pulverization process using a Z ball was performed. This aims at crushing and homogenizing the secondary particles. However, the powder obtained by the present coprecipitation method is, according to the wet laser diffraction particle size distribution measurement,
It is possible to omit this ball milling process, since particles of 1 μm or less occupy about 80% of the whole, and even large secondary particles have a particle size of 10 to 20 μm.
【００２５】(1.1.7) 一次仮焼：得られた粉末を、１，
１５０℃×５hrで一次仮焼（熱処理）を行った。仮焼時
には、主にＮｉＯの微粉が焼結現象により他のＮｉＯ粉
に合体する。また、Ｙ2Ｏ3 がＺｒＯ 2に徐々に固溶し
て結晶化する。一次仮焼後の粉粒径は平均粒径で９０〜
１１０μm 、ＢＥＴ値は２．５〜２．８m2/gであった。(1.1.7) Primary calcination: The obtained powder was
Primary calcination (heat treatment) was performed at 150 ° C. for 5 hours. During calcination, the NiO fine powder is mainly combined with other NiO powder by a sintering phenomenon. Further, Y 2 O 3 is gradually solid-dissolved in ZrO 2 and crystallized. The average particle size of the powder particles after primary calcination is 90-
It had a BET value of 2.5 to 2.8 m 2 / g.
【００２６】(1.1.8) 粉砕：以下諸元の気流粉砕により
一次仮焼した粉を径２μm 以下に粉砕した。粉砕後の粒
径及びＢＥＴ値は平均粒径０．５４μm 、ＢＥＴ値３．
３m2/gであった。なお、粉砕方法は、微粉砕が可能であ
れば、ボールミル粉砕等の他の手段を用いることができ
る。 気流粉砕諸元： 粉砕機；日清製粉（株） 圧力＝６kgf/cm2G 空気量＝０．８m3/min(1.1.8) Pulverization: Powder preliminarily calcined by air flow pulverization having the following specifications was pulverized to a diameter of 2 μm or less. The particle diameter and BET value after pulverization are 0.54 μm in average particle diameter and BET value of 3.
It was 3 m 2 / g. As the pulverization method, other means such as ball mill pulverization can be used as long as fine pulverization is possible. Specifications of air flow crusher: crusher; Nisshin Flour Milling Co., Ltd. Pressure = 6kgf / cm 2 G Air volume = 0.8m 3 / min
【００２７】(9) 二次仮焼：粉砕した粉を１，０００℃
×５hrの条件で二次仮焼した。この二次仮焼は、粉砕粉
を再び軽く焼結させることにより、粉砕粉の焼結性を抑
制することを目的とする。二次仮焼後の粒径及びＢＥＴ
値は平均粒径１．２μm 、ＢＥＴ値２．４m2/gであっ
た。(9) Secondary calcination: milled powder at 1,000 ° C
Secondary calcination was performed under the condition of × 5 hr. This secondary calcination aims to suppress the sinterability of the pulverized powder by lightly sintering the pulverized powder again. Particle size and BET after secondary calcination
The average particle size was 1.2 μm and the BET value was 2.4 m 2 / g.
【００２８】（１．２）粉末混合法：出発原料のＮｉＯ
粉末としては市販の平均粒径２μm のＮｉＯ粉体を用い
た。ＹＳＺ粉末としては第一稀元素化学工業製を用い
た。ＮｉＯの平均粒径は２μm、ＹＳＺの平均粒径は
０．４μm であった。両者のＮｉＯ／ＹＳＺ比＝７０／
３０となるようボールミル（ボール材質：ジルコニアボ
ール）で水を媒体として混合した。この混合粉を乾燥、
解砕し、その後９００℃×１０Hr、大気雰囲気中で仮焼
してＮｉＯ／ＹＳＺ複合粉末を得た。(1.2) Powder mixing method: Starting material NiO
A commercially available NiO powder having an average particle size of 2 μm was used as the powder. As the YSZ powder, a product manufactured by Daiichi Rare Element Chemical Industry was used. The average particle size of NiO was 2 μm, and the average particle size of YSZ was 0.4 μm. NiO / YSZ ratio of both = 70 /
Water was mixed with a ball mill (ball material: zirconia balls) so as to be 30 using water as a medium. Dry this mixed powder,
It was crushed and then calcined in an air atmosphere at 900 ° C. for 10 hours to obtain a NiO / YSZ composite powder.
【００２９】（１．３）蒸発乾固法 出発原料として上記ＮｉＯ粉末及びジルコニウム・イッ
トリア硝酸水溶液（８mol％Ｙ2 Ｏ3 （換算）、酸化物
換算含有量２３．４wt％）を用いた。これらをスターラ
ーで混合し、その後２００℃で蒸発乾固させた。この乾
固粉を解砕後、上記（１．１）と同じ条件で仮焼してＮ
ｉＯ／ＹＳＺ複合粉末を得た。(1.3) Evaporation and Drying Method The above NiO powder and zirconium-yttria nitric acid aqueous solution (8 mol% Y 2 O 3 (converted), oxide converted content 23.4 wt%) were used as starting materials. These were mixed with a stirrer and then evaporated to dryness at 200 ° C. After crushing this dry solid powder, it is calcined under the same conditions as in (1.1) above and N
An iO / YSZ composite powder was obtained.
【００３０】（２）成膜・焼成：得られたＮｉ／ＹＳＺ
サーメット原料粉末２８部と、有機溶剤としてのエタノ
ールを６８部、分散剤としてのポリカルボン酸エステル
を１部、消泡剤としての高分子界面活性剤を１部、バイ
ンダーとしてのエチルセルロースを２部混合してスラリ
ーを作製した。このスラリーをＹＳＺ基板上にディッピ
ングによりスラリーコートした。これを乾燥後１，４０
０℃で焼成した。得られたサーメット膜の厚さは８０μ
m 、気孔率は２８％であった。また、同様な手法で、緻
密なＹＳＺ薄膜が表面にコーティングされたＹＳＺ多孔
質基板上に上記スラリーをコートして、乾燥後１，４０
０℃で焼成した。(2) Film formation and firing: Ni / YSZ obtained
28 parts of cermet raw material powder, 68 parts of ethanol as organic solvent, 1 part of polycarboxylic acid ester as dispersant, 1 part of polymeric surfactant as defoaming agent, and 2 parts of ethyl cellulose as binder Then, a slurry was prepared. The slurry was coated on the YSZ substrate by dipping. 1,40 after drying this
Baking at 0 ° C. The thickness of the obtained cermet film is 80μ.
m 2, porosity was 28%. In addition, by the same method, the above slurry is coated on a YSZ porous substrate having a dense YSZ thin film coated on the surface thereof, and dried 1,40
Baking at 0 ° C.
【００３１】（３）還元、導電率測定：焼成により得ら
れたサーメット膜を、Ｈ2 １０％含有Ｎ2 雰囲気、1,00
0 ℃×１０Hrで還元した。その後、四端子法により導電
率を測定した。その結果を表１に示す。また、耐久性試
験として、１，０５０℃、１５％Ｈ2 含有Ｎ2 雰囲気で
１，０００時間保持した後の導電率も測定した。それら
の結果については後述する。(3) Reduction, conductivity measurement: The cermet film obtained by firing was treated with H 2 10% in N 2 atmosphere, 1,00
It was reduced at 0 ° C. × 10 hours. Thereafter, the conductivity was measured by a four-terminal method. Table 1 shows the results. In addition, as a durability test, the electrical conductivity was also measured after the sample was held at 1,050 ° C. in a N 2 atmosphere containing 15% H 2 for 1,000 hours. The results will be described later.
【００３２】（４）組織観察：試料断面を研磨して、粒
子径と粒界数の測定を行った。この際研磨方法は次のと
おりである。まず、試料を樹脂に含浸させ、気孔部に樹
脂を浸透させて固化させた。次に試料断面が表面に出て
くるまで＃２００で荒削りし、次いで、＃６００、＃１
０００で表面研磨を行い、最終的に１μm 、０．２５μ
m のダイヤモンドペーストで仕上げの研磨を行った。こ
の研磨試料について、ＳＥＭ観察及びＥＤＸによりＺｒ
及びＮｉの元素分布のマッピングを行った。ＳＥＭ写真
（図１参照）より粒子の分布をトレースし、それにマッ
ピング図を重ね合わせて元素分布図（図２参照）を作成
した。この元素分布から線分（長さ２４．２μm 、各試
料１８本）の横切る粒界数を求めた。粒界数及びＮｉ／
ＹＳＺ粒界割合の測定結果は表１及び表２に示す。(4) Structure observation: The cross section of the sample was polished and the particle size and the number of grain boundaries were measured. At this time, the polishing method is as follows. First, the sample was impregnated with resin, and the resin was permeated into the pores and solidified. Next, rough cut with # 200 until the sample cross section appears on the surface, then # 600, # 1
Surface polishing at 000, and finally 1μm, 0.25μ
Final polishing was performed with m 2 diamond paste. For this polished sample, Zr was observed by SEM and EDX.
The element distributions of Ni and Ni were mapped. The distribution of particles was traced from the SEM photograph (see FIG. 1), and the mapping diagram was superimposed on the trace to create an element distribution diagram (see FIG. 2). From this element distribution, the number of grain boundaries across a line segment (length 24.2 μm, 18 samples in each sample) was determined. Number of grain boundaries and Ni /
The measurement results of the YSZ grain boundary ratio are shown in Tables 1 and 2.
【００３３】（５）試験結果：結果を表１及び表２に示
す。(5) Test results: The results are shown in Tables 1 and 2.
【００３４】[0034]
【表１】 [Table 1]
【００３５】[0035]
【表２】 [Table 2]
【００３６】平均粒径は共沈法≪蒸発乾固法＜粉末混合
法であった。また、Ｎｉ／ＹＳＺ粒界数の割合は共沈法
＞蒸発乾固法≫粉末混合法であった。この理由は共沈法
では微細で均一な粒子が生成するので熱処理工程や粉砕
工程によっても各成分の極端な凝集や分離が起こり難い
ので、粒径が小さくしかも各成分が均一に混ざりあった
組織が得られる。その結果、平均粒径が小さくしかも各
成分間の粒界数が多い。蒸発乾固法では液相からの固相
析出が徐々に起こるために粗粒子が生成し易く、その結
果、共沈法よりは大きな粒径を有した構造となり易い。
ＮｉＯとＹＳＺの粒径がＮｉＯ＞ＹＳＺとなっている
が、これは析出時に粒生長のし易いことによる。この粒
子径の違いによって、粒界数が減少するとともに、組織
の均一性が共沈法の場合よりも劣るために、Ｎｉ／ＹＳ
Ｚ粒界数が少なくなったと考えられる。粉末混合法では
粒子の凝集が解けないことや、溶媒乾燥時の粒子沈降に
よって成分の分離が起こり、局所的に粗粒子が存在する
構造となった。この結果、粒界数が少なくなったと考え
られる。The average particle size was the coprecipitation method << evaporation and dryness method <powder mixing method. The ratio of the number of Ni / YSZ grain boundaries was coprecipitation method> evaporation dryness method >> powder mixing method. The reason for this is that the coprecipitation method produces fine and uniform particles, so that extreme aggregation and separation of each component is less likely to occur even in the heat treatment process and the pulverization process, so that the grain size is small and the structure in which each component is uniformly mixed Is obtained. As a result, the average grain size is small and the number of grain boundaries between the components is large. In the evaporation-drying method, solid phase precipitation from the liquid phase gradually occurs, so that coarse particles are easily generated, and as a result, a structure having a larger particle size is more likely to be formed than in the coprecipitation method.
The grain sizes of NiO and YSZ are NiO> YSZ, but this is because grain growth easily occurs during precipitation. Due to this difference in particle size, the number of grain boundaries decreases and the uniformity of the structure is inferior to that in the case of the coprecipitation method.
It is considered that the number of Z grain boundaries decreased. In the powder mixing method, agglomeration of the particles could not be resolved, and the components were separated due to particle settling during solvent drying, resulting in a structure in which coarse particles exist locally. As a result, it is considered that the number of grain boundaries decreased.
【００３７】初期導電率は、共沈法≫蒸発乾固法＞粉末
混合法であった。この理由は共沈法の組織は均一分散型
で、Ｎｉの結合が三次元的に均一にネットワークされて
いるために導電パスの切れが少なく良好な特性が得られ
る。蒸発乾固法では粒子が大きくなり三次元的な結合が
切断される様になるために、導電率が低くなる。また、
粉末混合法では、局所的なＮｉの分布が起こる構造とな
り、導電パスがより少なくなるために導電率が小さくな
ったものと考えられる。１，０００時間後の導電率は、
共沈法では初期状態よりも特性がやや向上したのに対し
て、蒸発乾固法ではやや低下、粉末混合法では大きく低
下した。試料表面を観察すると、共沈法による成膜体で
は変化が観られないのに対して、蒸発乾固法による試料
では少しのクラックが、粉末混合法による試料では多く
のクラックが膜表面に発生していることが確認され、こ
れが導電率の低下をもたらしたと容易に推測された。The initial conductivity was coprecipitation method >> evaporation and dryness method> powder mixing method. The reason for this is that the structure of the coprecipitation method is a uniform dispersion type, and since the Ni bonds are three-dimensionally and uniformly networked, there are few breaks in the conductive paths and good characteristics can be obtained. In the dry evaporation method, the particles become large and the three-dimensional bond is broken, so that the conductivity becomes low. Also,
It is considered that the powder mixing method has a structure in which a local distribution of Ni occurs, and the number of conductive paths is smaller, so that the conductivity is smaller. The conductivity after 1,000 hours is
In the coprecipitation method, the properties were slightly improved compared to the initial state, while in the evaporation-drying method, it was slightly decreased, and in the powder mixing method, it was significantly decreased. When observing the sample surface, no change is observed in the film formed by the coprecipitation method, whereas a few cracks occur in the sample by the evaporation-drying method and many cracks in the sample by the powder mixing method. Was confirmed, and it was easily speculated that this resulted in a decrease in conductivity.
【００３８】[0038]
【発明の効果】以上の説明から明らかなように、本発明
は以下の効果を発揮する。 長時間高温にさらされた場合にもＮｉの凝集がほと
んど生じることがないＮｉ／ＹＳＺサーメットを提供で
きる。そのため、クラックや剥離等の燃料電極の破壊や
電気抵抗の増大といったＮｉ凝集に起因する燃料電極の
特性劣化を改善することができる。 製法に関係なく、初期特性のみならず耐久性をも含
んだ燃料電極の状態を判断できる。また、原料粉末のロ
ット間の特性ばらつきも判断でき、製品の特性を安定さ
せることができる。As is apparent from the above description, the present invention exhibits the following effects. It is possible to provide a Ni / YSZ cermet in which Ni agglomeration hardly occurs even when exposed to a high temperature for a long time. Therefore, it is possible to improve the deterioration of the characteristics of the fuel electrode due to Ni agglomeration such as cracking or peeling of the fuel electrode and increase in electrical resistance. Regardless of the manufacturing method, the state of the fuel electrode including not only the initial characteristics but also the durability can be judged. Further, it is possible to determine the variation in the characteristics of the raw material powder between lots, and it is possible to stabilize the characteristics of the product.
【図１】本発明の実施例及び比較例のＮｉ／ＹＳＺサー
メット膜のＳＥＭ組織写真である。FIG. 1 is an SEM micrograph of Ni / YSZ cermet films of Examples and Comparative Examples of the present invention.
【図２】本発明の実施例及び比較例のＮｉ／ＹＳＺサー
メット膜のＥＤＸ観察結果を示す図である。FIG. 2 is a diagram showing EDX observation results of Ni / YSZ cermet films of Examples and Comparative Examples of the present invention.
Claims (3)
ニア）の粒子の焼結体からなるＮｉ／ＹＳＺサーメット
であって；Ｎｉ／ＹＳＺ組成比が２４／７６〜６４／３
６wt％であり、 粒子の平均粒径が２μm 以下であり、 該サーメットを貫通する線分が横切る粒界の数におい
て、 （ＮｉとＹＳＺとの粒界数／全粒界数）≧０．４ ここで全粒界数＝ＮｉとＹＳＺとの粒界数＋ＹＳＺとＹ
ＳＺとの粒界数＋ＮｉとＮｉとの粒界数、 であることを特徴とするＮｉ／ＹＳＺサーメット。1. A Ni / YSZ cermet comprising a sintered body of particles of Ni and YSZ (yttria-stabilized zirconia); Ni / YSZ composition ratio is 24/76 to 64/3.
6 wt%, the average particle size of the particles is 2 μm or less, and the number of grain boundaries crossed by a line segment passing through the cermet is (the number of grain boundaries between Ni and YSZ / the number of all grain boundaries) ≧ 0.4 Here, the total number of grain boundaries = the number of grain boundaries between Ni and YSZ + YSZ and Y
Ni / YSZ cermet, wherein the number of grain boundaries with SZ + the number of grain boundaries with Ni and Ni.
ｉ／ＹＳＺサーメットを製造する方法であって；湿式法
により、Ｎｉ、Ｚｒ、Ｙ及び酸素を含む混合物を得る湿
式混合工程と、 該混合物を分解して上記各金属の酸化物を含む粉粒体を
得る分解工程と、 該粉粒体を仮焼する一次仮焼工程と、 仮焼後の粉粒体（ＮｉＯ／ＹＳＺ複合粉末）を粉砕する
粉砕工程と、 この粉砕工程で得られた粉砕粉を再度仮焼する二次仮焼
工程と、 二次仮焼したＮｉＯ／ＹＳＺ複合粉末を、スラリーコー
ト法により基体上に成膜する工程と、 このＮｉＯ／ＹＳＺ複合粉末膜を１，２００〜１，４５
０℃で焼成する工程と、 このＮｉＯ／ＹＳＺ複合粉末
膜を還元する工程と、を含むことを特徴とするＮｉ／Ｙ
ＳＺサーメットの製造方法。2. N consisting of a sintered body of particles of Ni and YSZ
A method for producing an i / YSZ cermet; a wet mixing step of obtaining a mixture containing Ni, Zr, Y and oxygen by a wet method, and a granular material containing the oxide of each metal by decomposing the mixture. A primary calcination step of calcination of the powder and granules, a pulverization step of pulverizing the powder and granules (NiO / YSZ composite powder) after calcination, and a pulverized powder obtained in this pulverization step Secondary calcination step of calcination again, a step of depositing the secondary calcinated NiO / YSZ composite powder on the substrate by a slurry coating method, and the NiO / YSZ composite powder film of 1,200 to 1 , 45
Ni / Y characterized by including a step of firing at 0 ° C. and a step of reducing the NiO / YSZ composite powder film.
Manufacturing method of SZ cermet.
ｉ／ＹＳＺサーメットを製造する方法であって；Ｎｉイ
オン、Ｚｒイオン、Ｙイオンを所望割合で含む原料溶液
を調整する溶液調整工程と、 共沈溶液を上記原料溶液に混合して、上記各金属の１種
以上及び酸素を含む固体物質（共沈物質）を上記原料溶
液から共沈させる共沈工程と、 該共沈物質を分解して上記各金属の酸化物を含む粉粒体
を得る分解工程と、 該粉粒体を仮焼する仮焼工程と、 仮焼後の粉粒体（ＮｉＯ／ＹＳＺ複合粉末）を粉砕する
粉砕工程と、 この粉砕工程で得られた粉砕粉を再度仮焼する二次仮焼
工程と、 二次仮焼したＮｉＯ／ＹＳＺ複合粉末を、スラリーコー
ト法により基体上に成膜する工程と、 このＮｉＯ／ＹＳＺ複合粉末膜を1,200 〜1,450 ℃で焼
成する工程と、 このＮｉＯ／ＹＳＺ複合粉末膜を還元する工程と、を含
むことを特徴とするＮｉ／ＹＳＺサーメットの製造方
法。3. N consisting of a sintered body of particles of Ni and YSZ
A method for producing an i / YSZ cermet; a solution adjusting step of adjusting a raw material solution containing Ni ions, Zr ions, and Y ions in a desired ratio; A coprecipitation step of coprecipitating a solid substance (coprecipitated substance) containing at least one of the above and oxygen from the above raw material solution, and decomposing the coprecipitated substance to obtain a granular material containing oxides of the above respective metals Process, a calcination process of calcination of the powder and granules, a pulverization process of crushing the powder and calcination substance (NiO / YSZ composite powder), and a pulverization powder obtained in the pulverization process again. Secondary calcination step, a step of forming a secondary calcinated NiO / YSZ composite powder on a substrate by a slurry coating method, and a step of firing this NiO / YSZ composite powder film at 1,200 to 1,450 ° C. A step of reducing the NiO / YSZ composite powder film, Method of manufacturing a Ni / YSZ cermet, which comprises a.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8143427A JPH09302438A (en) | 1996-05-15 | 1996-05-15 | Nickel/ysz cermet and its manufacture |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8143427A JPH09302438A (en) | 1996-05-15 | 1996-05-15 | Nickel/ysz cermet and its manufacture |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH09302438A true JPH09302438A (en) | 1997-11-25 |
Family
ID=15338479
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8143427A Pending JPH09302438A (en) | 1996-05-15 | 1996-05-15 | Nickel/ysz cermet and its manufacture |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH09302438A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009218146A (en) * | 2008-03-12 | 2009-09-24 | Inst Nuclear Energy Research Rocaec | Processing method of positive electrode increasing output density of solid oxide fuel cell membrane electrode assembly (sofc-mea) |
| JP2013079190A (en) * | 2004-07-13 | 2013-05-02 | Hyundai Motor Co Ltd | Method for producing nio-ceramic composite powder and nio-ceramic composite fuel electrode |
| JP2018503215A (en) * | 2015-09-18 | 2018-02-01 | エルジー・ケム・リミテッド | Electrode slurry for solid oxide fuel cell, green sheet for electrode for solid oxide fuel cell, electrode for solid oxide fuel cell, solid oxide fuel cell, and method for producing electrode for solid oxide fuel cell |
| CN115747600A (en) * | 2022-11-15 | 2023-03-07 | 河北邯峰发电有限责任公司 | Laser cladding self-healing ceramic reinforced wear-resistant alloy coating material, composite material and preparation method thereof |
-
1996
- 1996-05-15 JP JP8143427A patent/JPH09302438A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2013079190A (en) * | 2004-07-13 | 2013-05-02 | Hyundai Motor Co Ltd | Method for producing nio-ceramic composite powder and nio-ceramic composite fuel electrode |
| JP2009218146A (en) * | 2008-03-12 | 2009-09-24 | Inst Nuclear Energy Research Rocaec | Processing method of positive electrode increasing output density of solid oxide fuel cell membrane electrode assembly (sofc-mea) |
| JP2018503215A (en) * | 2015-09-18 | 2018-02-01 | エルジー・ケム・リミテッド | Electrode slurry for solid oxide fuel cell, green sheet for electrode for solid oxide fuel cell, electrode for solid oxide fuel cell, solid oxide fuel cell, and method for producing electrode for solid oxide fuel cell |
| US10615420B2 (en) | 2015-09-18 | 2020-04-07 | Lg Chem, Ltd. | Electrode slurry of solid oxide fuel cell, green sheet for electrode of solid oxide fuel cell, electrode of solid oxide fuel cell, and method for manufacturing solid oxide fuel cell and electrode of solid oxide fuel cell |
| CN115747600A (en) * | 2022-11-15 | 2023-03-07 | 河北邯峰发电有限责任公司 | Laser cladding self-healing ceramic reinforced wear-resistant alloy coating material, composite material and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5306726B2 (en) | Fuel cell electrode-electrolyte composite powder and preparation method thereof | |
| JP5391391B2 (en) | Method for producing NiO-ceramic composite powder | |
| CN108832136B (en) | Composite oxygen electrode for solid oxide battery and preparation method thereof | |
| WO2004013882A2 (en) | Nano-composite electrodes and method of making the same | |
| JP5359499B2 (en) | Composite nickel oxide powder material for solid oxide fuel cell, method for producing the same, and fuel electrode material using the same | |
| US20090189115A1 (en) | Mixtures of nanoparticles | |
| JP5196502B2 (en) | Composite material suitable for use as an electrode material in SOC | |
| Xin et al. | Fabrication of dense YSZ electrolyte membranes by a modified dry-pressing using nanocrystalline powders | |
| KR100756518B1 (en) | Method of preparing a material for electrolysis | |
| JP2006040612A (en) | Fuel electrode raw material powder of solid electrolyte fuel cell, its manufacturing method, fuel electrode, and solid electrolyte fuel cell | |
| JP2000353530A (en) | MANUFACTURE OF NiO AND/OR Ni/YSZ COMPOSITE POWDER AND MANUFACTURE OF SOLID ELECTROLYTE FUEL CELL USING THEREOF | |
| Xi et al. | Preparation and characterization of Ni-YSZ composite electrode for solid oxide fuel cells by different co-precipitation routes | |
| JP3336851B2 (en) | Method for producing Ni / YSZ cermet raw material powder | |
| JPH09302438A (en) | Nickel/ysz cermet and its manufacture | |
| Kalinina et al. | Formation of Bilayer Thin-Film Electrolyte on Cathode Substrate by Electrophoretic deposition | |
| JP2008071668A (en) | Composite particle powder and its manufacturing method, electrode for solid oxide fuel cell and its manufacturing method, and solid oxide fuel battery cell | |
| JPH11343123A (en) | Production of ni or nio/ysz composite powder, and formation of fuel electrode membrane using the same | |
| JP3604210B2 (en) | Method for producing NiO / YSZ composite powder | |
| WO2023079877A1 (en) | Oxide ion–conducting solid electrolyte | |
| JP7477729B2 (en) | Composite oxide powder and its manufacturing method | |
| Kalinina et al. | Preparation of thin bilayer coatings based on lanthanum, nickel, and cerium mixed oxides by electrophoretic deposition | |
| EP4180398A1 (en) | Perovskite-type composite oxide powder | |
| EP4137459A1 (en) | Composite oxide powder | |
| ZHENG et al. | Synthesis and characterization of Ce0. 8Sm0. 2O1. 9 nanopowders using an acrylamide polymerization process | |
| Nie et al. | The sintering temperature effect on electrochemical properties of |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20070410 |
|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20071023 |