http://support.spring8.or.jp/Report_JSR/PDF_IAe_ALL/IAe_11A1722.pdf

2011A1722                       BL14B2ⓑ㔠ࢆ౑⏝ࡋ࡞࠸⇞ᩱ㟁ụ࢝ࢯ࣮ࢻゐ፹ࡢ XAFS ࡟ࡼࡿࡑࡢሙ ᐃ 4
In-situ XAFS of Oxygen Reduction Reaction Electrocatalysts forNon-platinum Fuel Cell Part 4ᮅ⃝ ᾈ୍㑻 a, ᆏᮏ ཭࿴ a , ⏣୰ ⿱ஂ a, ᯇᮧ ኱ᶞ b, ⏣ᮧ ࿴ஂ b, す⏿ ಖ㞝 b
Koichiro Asazawaa, Tomokazu Sakamotoa, Hirohisa Tanakaa, Daiju Matsumurab,Kazuhisa Tamurab, Yasuo Nishihatabaࢲ࢖ࣁࢶᕤᴗ㻔ᰴ㻕, b㻔⊂㻕᪥ᮏཎᏊຊ◊✲㛤ⓎᶵᵓaDaihatsu Motor Co., Ltd., bJAEA࢔ࢽ࢜ࣥ஺᥮⭷ᙧ⇞ᩱ㟁ụ࡟⏝࠸ࡽࢀࡿ࢝ࢯ࣮ࢻゐ፹ࡢᵓ㐀ࢆ᫂☜࡟ࡍࡿࡓࡵ࡟ࠊX ⥺྾཰ᚤ⣽ᵓ㐀㻔XAFS㻕 ᐃ࡟ྲྀࡾ⤌ࢇ࡛࠸ࡿࠋ⌧ᅾὀ┠ࡋ࡚࠸ࡿ࣮࢟ࣞࢺゐ፹ࡣ୰ᚰ㔠ᒓࡀ㓄఩Ꮚ࡟㓄఩ࡉࢀ࡚࠾ࡾࠊࡑࡢ⤌ࡳྜࢃࡏ࡟ࡼࡾᛶ⬟ࢆ኱ᖜ࡟ኚ໬ࡉࡏࡿࠋ௒ᅇࡣࡇࢀࡲ࡛ゎᯒࢆ⾜࡞ࡗ࡚ࡁࡓࢥࣂࣝࢺ㸫࣏ࣜࣆ࣮ࣟࣝゐ፹࡟௦࠼࡚ࠊ㕲㸫ࣇ࢙ࢼࣥࢺࣟࣜࣥ㘒య࠿ࡽ࡞ࡿゐ፹ࡢᵓ㐀ゎᯒࢆ⾜࠸ࠊ᭦࡟ࡑࡢሙ㻔in-situ㻕 ᐃࢆヨࡳࡓࠋ࣮࣮࢟࣡ࢻ㸸 ⇞ᩱ㟁ụࠊ࢔ࢽ࢜ࣥ஺᥮⭷ᙧࠊ㠀ⓑ㔠࢝ࢯ࣮ࢻゐ፹ࠊIn-situ XAFS⫼ᬒ࡜◊✲┠ⓗ㸸᪥ᮏ࡟࠾࠸࡚⮬ື㌴࠿ࡽᨺฟࡉࢀࡿ஧㓟໬Ⅳ⣲㔞ࡣ඲యࡢ⣙ᅄศࡢ୍ࡶ༨ࡵ࡚࠾ࡾࠊ2020 ᖺࡲ࡛࡟ 1990 ᖺẚ࡛ 25%๐ῶࡍࡿࡓࡵ࡟ࡣࠊ᪩ᛴ࡞ᢏ⾡㛤Ⓨࡀᚲせ࡛࠶ࡿࠋࡑࡇ࡛ḟୡ௦ࢡ࣮ࣜࣥᢏ⾡࡜ࡋ࡚ᮇᚅࡉࢀ࡚࠸ࡿࡢࡀࠊ㉮⾜᫬࡟ࡣ ᐊຠᯝ࢞ࢫࢆ඲ࡃ᤼ฟࡋ࡞࠸⇞ᩱ㟁ụ㌴࡛࠶ࡿࠋࢲ
࢖ࣁࢶ࡛ࡣ⌧ᅾࠊ࢔ࣝ࢝ࣜᛶࡢ࢔ࢽ࢜ࣥ஺᥮⭷ࢆ⏝࠸ࡓࠕᾮయ⇞ᩱᙧ࢔ࢽ࢜ࣥ⇞ᩱ㟁ụࠖࡢ᪩ᮇᐇ⌧࡟ྥࡅ࡚ࠊᅜෆእࡢ኱Ꮫ࣭◊✲ᶵ㛵࡜㐃ᦠࡋ࡚◊✲㛤Ⓨࢆ⾜ࡗ࡚࠸ࡿࠋⓎ㟁ࡢᚰ⮚㒊ศ࡛࠶ࡿ㟁ᴟゐ፹ࡢ㛤Ⓨ࡛ࡣࠊ⇞ᩱഃࡢ࢔ࣀ࣮ࢻゐ፹࠾ࡼࡧ✵Ẽഃࡢ࢝ࢯ࣮ࢻゐ፹࡟࠾࠸࡚ࠊ㠀ⓑ㔠࡞ࡀࡽⓑ㔠ࡢᛶ⬟ࢆ㉸࠼ࡿฟຊᛶ⬟ࡀᚓࡽࢀ࡚࠾ࡾࠊᐇ⏝໬࡟╔ᐇ࡟㏆࡙࠸࡚࠸ࡿ[1]ࠋ࢝ࢯ࣮ࢻ㟁ᴟゐ፹࡜ࡋ࡚ࡣ㔠ᒓࢆ㓄఩Ꮚ࡟㓄఩ࡉࡏࡓ࣮࢟ࣞࢺゐ፹ࡢ㛤Ⓨ࡟ὀຊࡋ࡚࠾ࡾࠊࡇࢀࡲ࡛ࠊCo ࣮࢟ࣞࢺゐ፹࡟ࡼࡾ⇞ᩱ㟁ụ≉ᛶࡀ㣕㌍ⓗ࡟ྥୖࡍࡿࡇ࡜ࢆሗ࿌ࡋࡓ[2]ࠋࡋ࠿ࡋ࡞ࡀࡽ㓟⣲㑏ඖ཯ᛂࡢ࣓࢝ࢽࢬ࣒࠾ࡼࡧࡑࡢάᛶⅬ࡟ࡘ࠸࡚ࡣㅖㄝࡀ࠶ࡾᮍゎ࡛᫂࠶ࡿࠋᡃࠎࡣࡇࢀࡲ࡛ࡢヨ㦂⤖ᯝ࠿ࡽ Co ࢆάᛶⅬ࡜⪃࠼ Co ࣮࢟ࣞࢺゐ፹ࡢ in-situ ᐃ࡟ྲྀࡾ⤌ࡳࠊ㓟⣲㑏ඖ཯ᛂ࡟࠾ࡅࡿ㟁఩ኚ໬࡟క࠺ᵓ㐀ࡢኚ໬ࢆᤊ࠼ࡿ஦࡟ᡂຌࡋࡓ㻔2009B1874ࠊ2009B2083ࠊ
2010A1872㻕[3]ࠋࡉࡽ࡟ࠊCo ࣮࢟ࣞࢺゐ፹ࡼࡾ㧗࠸ゐ፹άᛶࢆ♧ࡍ㕲㻔Fe㻕࣮࢟ࣞࢺゐ፹࡟ࡘ࠸࡚ࡶ
in-situ ᐃࢆ㛤ጞࡋ㻔2010B1852㻕ࠊCo ྠᵝ࡟㟁఩࡟ࡼࡗ࡚ Fe-k ྾཰➃ XANES ࢫ࣌ࢡࢺࣝࡸ EXAFSࢫ࣌ࢡࢺࣝࡢࣇ࣮࢚ࣜኚ᥮࡟ࡼࡗ࡚ᚓࡽࢀࡓືᚄศᕸ㛵ᩘ࡟ኚ໬ࡀぢࡽࢀࡿࡇ࡜ࢆ☜ㄆࡋࡓࠋ௒ᅇࡢᐇ㦂ࡣ Fe ࣮࢟ࣞࢺゐ፹⣔࡟ࡘ࠸࡚ࠊ↝ᡂ๓ࡢゐ፹ཎᩱ࡜ẚ㍑ࡍࡿ஦࡟ࡼࡾ↝ᡂ ᗘࢆኚ໬ࡉࡏࡓ࡜ࡁࡢゐ፹ึᮇᵓ㐀ࡢ㐪࠸ࢆᢕᥱࡋࡓୖ࡛ in-situ ᐃࢆ⾜ࡗࡓࠋIn-situ ᐃ࡛ࡣ㓟⣲ศᅽࢆኚ໬ࡉࡏࡿࡇ࡜࡟ࡼࡗ࡚㓟⣲ศᅽࡀゐ፹ᵓ㐀ኚ໬࡟ཬࡰࡍᙳ㡪࡟ࡘ࠸࡚ヲ⣽࡟ㄪᰝࡋࡓࠋᐇ㦂㸸Fe ࣮࢟ࣞࢺゐ፹ࡣ᪤ሗ[4]ࢆཧ⪃࡟ࡋࠊ㓑㓟㕲⏤᮶ࡢ Fe ࡜ࣇ࢙ࢼࣥࢺࣟࣜࣥ࠿ࡽ࡞ࡿ㘒యࢆ
800Υ࠿ࡽ 1000Υ࡛↝ᡂࡍࡿ஦࡟ࡼࡾྜᡂࡋࡓࠋ↝ᡂ ᗘࢆኚ࠼ࡓゐ፹ࡢึᮇ≧ែࢆࠊ㓑㓟㕲⁐ᾮࡸ↝ᡂ๓ࡢゐ፹ཎᩱࢆཧ⪃࡟ᵓ㐀ࢆᢕᥱࡋࡓୖ࡛ in-situ ᐃࢆ⾜ࡗࡓࠋIn-situ ᐃࡢ⿦⨨࣭ࢭࣝࡣ 2010B1852 ࡜ྠᵝ࡛࠶ࡿࠋ ᐃ㟁ᴟࡣゐ፹ࢆࢼࣇ࢕࢜ࣥ⁐ᾮ࡜ࡶ࡟࣮࣮࢝࣎ࣥ࣌ࣃ࣮ୖ࡟ሬᕸࡋᙧᡂࡋࡓࠋࢭࣝࡣ 3 㟁ᴟᆺ࡛࠶ࡾࣜࣇ࢓ࣞࣥࢫ㟁ᴟ࡟ࡣ Hg/HgOࠊ࢝࢘ࣥࢱ࣮㟁ᴟ࡟ࡣⓑ㔠⥺ࢆ⏝࠸ࠊ࣏ࢸࣥࢩ࢜ࢫࢱࢵࢺ࡛㟁఩ࢆ-400 mV ࠿ࡽ 100 mV ࡲ࡛ 100 mV้ࡳ࡟ไᚚࡋࡓࠋ㟁ゎᾮࡢ౪⤥๓ࡢゐ፹≧ែࢆᢕᥱࡋࡓᚋ࡟ࠊヨᩱ㠃࡟ 45|࡛ᨺᑕගࢆධᑕࡉࡏࠊ19 ⣲Ꮚ SSD ᳨ฟჾࢆ౑⏝ࡋࡓ⺯ගἲ࡟ࡼࡿ Fe-k ྾཰➃ࡢ in-situ XAFS ᐃࢆ⾜࡞ࡗࡓࠋ ᐃ࡟࠾࠸࡚ࡣ㓟⣲㑏ඖ࡟࠾ࡅࡿ㓟⣲ศᅽࡢᵓ㐀࡬ࡢᙳ㡪ࢆẚ㍑ࡍࡿࡓࡵࠊ❅⣲ࠊ࢚࢔ࠊ㓟⣲ࡢ 3 ✀ࡢ࢞ࢫ࡛ࣂࣈࣜࣥࢢࡋࡓ㟁ゎᾮࢆ౪⤥ࡋ࡚ Fe-k ྾཰➃ XANES ࢫ࣌ࢡࢺࣝࡢ㐪࠸ࢆẚ㍑ࡋࡓࠋ
⤖ᯝ࠾ࡼࡧ⪃ᐹ㸸
㓑㓟㕲㻔FeAc㻕࠾ࡼࡧࣇ࢙ࢼࣥࢺࣟࣜࣥ࡜㘒ᙧᡂࡋࡓཎᩱ㻔FePhen㻕ࡢ Fe-k ྾཰➃ XANES ࢫ࣌ࢡࢺࣝࡢ㐪࠸ࢆᅗ 1 ࡢձ࡟♧ࡍࠋ㓑㓟㕲㻔FeAc㻕ᵓ㐀ࡀࣇ࢙ࢼࣥࢺࣟࣜࣥ࡜㘒ᙧᡂࡍࡿࡇ࡜࡟ࡼࡗ࡚ᵓ
㐀ࢆኚ࠼࡚࠸ࡿࡇ࡜ࡀศ࠿ࡿࠋᅗ 1 ࡢղ࡟↝ᡂ๓࠾ࡼࡧ↝ᡂ ᗘࢆ 800Υ࠿ࡽ 1000Υ࡟ኚ໬ࡉࡏ
ࡓ᫬ࡢ Fe-k ྾཰➃ࡢ㐪࠸ࢆ♧ࡍࠋ↝ᡂ࡟ࡼࡗ࡚ᚎࠎ࡟㘒యᵓ㐀ࡀᔂࢀࠊ↝ᡂ ᗘࡣ 1000Υ࡛ࡣ࠿࡞ࡾ࣓ࢱࣝࡀ⏕ᡂࡋ࡚࠸ࡿࡇ࡜ࡀศ࠿ࡿࠋ
ḟ࡟ 900Υ↝ᡂࡋࡓゐ፹ࢆ⏝࠸ in-situ ᐃࢆ⾜ࡗࡓࠋᅗ 2 ࡟㓟⣲౪⤥᫬ࡢ㟁఩-400 mV ࡜ 100 mV
ࡢẚ㍑ࢆ♧ࡍࠋ྾཰➃ᵓ㐀࡟㐪࠸ࡀ࠶ࡾࠊ㓟⣲㑏ඖ཯ᛂ࡟ᑐࡍࡿ Fe ࡢ౯ᩘኚ໬ࡀ☜ㄆ࡛ࡁࡓࠋࡋ
࠿ࡋ࡞ࡀࡽ-400 mV ࡛㓟⣲ศᅽࡢᙳ㡪ࢆẚ㍑ࡋࡓࡀ኱ࡁ࡞ᕪ␗ࡀぢࡽࢀ࡞࠿ࡗࡓࠋࡑࡢ⌮⏤࡜ࡋ࡚ࡣ㓟⣲྾╔࡟ᑐࡍࡿ㓟⣲ศᅽࡢᙳ㡪ࡀᑡ࡞࠿ࡗࡓࠊ࠶ࡿ࠸ࡣࠊ㓟⣲㑏ඖ཯ᛂࡢ୰㛫య㻔㐣㓟໬Ỉ⣲࢖࢜ࣥ㻕྾╔ࡢᙳ㡪ࡀ኱ࡁ࠿ࡗࡓࡓࡵ࡜⪃࠼ࡿࠋ௒ᚋࡣ୰㛫యࡢᙳ㡪ࢆ☜ㄆࡍࡿࡓࡵ࡟୰㛫య㝖ཤ᮲௳ࢆタᐃࡋࠊΎί࡞ゐ፹⾲㠃࡛ࡢ㓟⣲ศᅽࡢᙳ㡪ࢆㄪᰝࡍࡿࠋ㻝㻚㻡㻝㻚㻡䐠㻲㼑㻭㼏㻝㻺㼛㼞㼙㼍㼘㼕㼦㼑㼐㻌䃦䃛㻔㻱㻕㻺㼛㼞㼙㼍㼘㼕㼦㼑㼐㻌䃦䃛㻔㻱㻕䐟㻲㼑㻼㼔㼑㼚㻜㻚㻡㻜㻣㻝㻜㻡㻣㻝㻝㻡㻣㻝㻞㻡㻣㻝㻟㻡㻝㻲㼑㻼㼔㼑㼚㻤㻜㻜㻯㻥㻜㻜㻯㻝㻜㻜㻜㻯㻜㻚㻡㻜㻣㻝㻜㻡㻣㻝㻝㻡㻱㻌䠄㼑㼂䠅㻣㻝㻞㻡㻣㻝㻟㻡㻱㻌䠄㼑㼂䠅ᅗ 1㸬㓑㓟㕲࡜ゐ፹ཎᩱࡢ Fe-k ྾཰➃ XANES ࢫ࣌ࢡࢺࣝձ࡜↝ᡂ ᗘ࡟ࡼࡿࢫ࣌ࢡࢺࣝࡢኚ໬ղ㻝㻜㻜㼙㼂㻺㼛㼞㼙㼍㼘㼕㼦㼑㼐㻌䃦䃛㻔㻱㻕㻙㻠㻜㻜㼙㼂㻝㻜㻚㻡㻜㻣㻝㻜㻡㻣㻝㻝㻡㻣㻝㻞㻡㻣㻝㻟㻡㻱㻌䠄㼑㼂䠅

 ᅗ 2㸬㓟⣲౪⤥᫬㟁఩ࡢ㐪࠸࡟ࡼࡿ 900Υ↝ᡂゐ፹ࡢ Fe-k ྾཰➃ XANES ࢫ࣌ࢡࢺࣝࡢኚ໬

௒ᚋࡢㄢ㢟㸸௒ᅇࡢ⤖ᯝࡔࡅ࡛ࡣ཯ᛂࣔࢹࣝࢆ❧࡚ࡿ஦ࡀ㞴ࡋ࠸ࠋ᭦࡞ࡿᐇ㦂࡟ࡼࡗ࡚཯ᛂࣔࢹࣝࢆ❧᱌ࡋࠊィ⟬໬Ꮫ࡟ࡼࡿ⿬௜ࡅࢆྲྀࡾࠊ㓟⣲㑏ඖ཯ᛂ᫬ࡢゐ፹ᵓ㐀ࢆ᫂☜࡟ࡍࡿࠋཧ⪃ᩥ⊩㸸[1] H. Tanaka et al., ECS Transactions, 16, 459, 㻔2008㻕.
[2] K. Asazawa, K. Yamada, H. Tanaka, A. Oka, M. Taniguchi, T. Kobayashi, Angew. Chem. Int. Ed., 46,8024, 㻔2007㻕.
[3] K. Asazawa et al., ECS Transactions, 33,㻌1751, 㻔2010㻕.
[4] M. Lefévre, J.P. Dodelet, P. Bertrand, J. Phys. Chem. Sect. B, 104, 11238, 㻔2000㻕.