      BL19B2

2011A1771

㧗㓟໬࢔࣑ࣝࢼ⓶⭷ࡢ┦ኚែᣲືಁ㐍࠾ࡼࡧ㐜ᘏຠᯝࡢࡑࡢሙほᐹ࡟ࡼࡿ᳨ウIn-situ measurement of phase transformation of Al2O3 scale during thehigh-temperature oxidation in various environmentsᯘ 㔜ᡂ a, బ఑ ຌ b, ᒣෆ ၨ a, すᒣ ెᏕ c, ᅵ஭ ᩍྐ c, ி ᑗྖ dShigenari Hayashia, Isao Saekib, Akira Yamauchia, Yoshitaka Nishiyamac, Takashi Doic, and Shoji Kyoda

໭ᾏ㐨኱Ꮫ኱Ꮫ㝔ᕤᏛ◊✲⛉, b ᐊ⹒ᕤᴗ኱ᏛᮦᩱᕤᏛ⛉, c㻔ᰴ㻕ఫ཭㔠ᒓᕤᴗ,d㛵す㟁ຊ㻔ᰴ㻕ab Hokkaido University, Muroran Institute of Technology, cSumitomo Metal Industries LTD. ,dKansai Electric Power CO. INC.
Fe ࠾ࡼࡧ Ni ࡢࢼࣀࢥ࣮ࢸ࢕ࣥࢢࢆ᪋ࡋࡓ Fe-Al ࡲࡓࡣ Ni-Al ྜ㔠ୖ࡟ࠊ኱Ẽ୰࠾ࡼࡧ H2/H2Oΰྜ࢞ࢫ୰㸦ప㓟⣲ศᅽୗ㸧ࡢ᪼ 㐣⛬࠾ࡼࡧ㧗 ➼ 㓟໬㐣⛬୰࡟ᙧᡂࡍࡿ Al2O3 ࢫࢣ࣮ࣝࡢ‽Ᏻᐃ┦࠿ࡽᏳᐃ  ┦࡬ࡢ┦ኚែᣲືࢆ㧗 ࢫࢸ࣮ࢪ࡜஧ḟඖ᳨ฟჾ PILATUS ࢆ⏝࠸ࡓࡑࡢሙほᐹᐇ㦂࡟ࡼࡾ᳨ウࡋࡓࠋFe2O3 ࡀ⏕ᡂࡋ࡞࠸ప㓟⣲ศᅽୗࡢ㓟໬࡛ࡣࠊFe ࢥ࣮ࢸ࢕ࣥࢢࢆ᪋ࡋࡓሙྜ࡛ࡶ -Al2O3 ࡀࡲࡎᙧᡂࡋࠊࡑࡢᚋ -Al2O3 ࡬࡜ኚែࡋࡓࠋࡲࡓࠊࡇࡢ㝿ࡢ┦ኚែ᫬㛫ࡣࠊ↓ࢥ࣮ࢸ࢕ࣥࢢヨᩱ࡜ẚ㍑ࡋ࡚㐜ᘏࡋࡓࠋࡲࡓࠊప㓟⣲ศᅽୗ࡛ࡢ㓟໬࡛ࡣࠊFe ࡜ Al ࡢ」ྜ㓟໬≀ࡀ⏕ᡂࡋࡓࠋྠᵝࡢࢫࣆࢿࣝᆺ」ྜ㓟໬≀, NiAl2O4, ࡢ⏕ᡂࡣࠊNi ࢥ࣮ࢸ࢕ࣥࢢヨᩱ࡛ࡶほᐹࡉࢀࡓࠋࡉࡽ࡟ࠊ-Al2O3 ࠿ࡽࡢᅇᢡ㠃ࡢ୍㒊ࡣࠊࢫࣆࢿࣝ┦ࡀ⏕ᡂࡋࡓ㝿ࡢࡳ࡟ほᐹࡉࢀࠊࡑࢀࡽࡢᅇᢡ㠃ࡣࢫࣆࢿࣝ┦࠿ࡽࡢᅇᢡ㠃࡜୍⮴ࡋࡓࠋ௒ᅇࡢ⤖ᯝࡣࠊⴭ⪅ࡽࡢᥦ᱌ࡍࡿࣔࢹࣝࡢṇᙜᛶࢆࡉࡽ࡟ᙉᅛ࡟ᨭᣢࡍࡿࡶࡢ࡛࠶ࡾࠊᮏศᯒᡭἲࡢ௒ᚋࡢᒎ㛤ࡀᮇᚅࡉࢀࡿࠋ࣮࣮࢟࣡ࢻ㸸 ࢔࣑ࣝࢼࢫࢣ࣮ࣝࠊ┦ኚែࠊ㧗㓟໬ࠊXRD ࡑࡢሙᐃࠊ༙ᑟయ᳨ฟჾ

⫼ᬒ࡜◊✲┠ⓗ㸸 ⴭ⪅ࡽࡣ࢔࣑ࣝࢼᙧᡂྜ㔠ࢆ㧗 㓟໬ࡋࡓ㝿ࠊึᮇ࡟⏕ᡂࡍࡿᡂ㛗ࡀ᪩ࡃಖㆤᛶ࡟ຎࡿ‽Ᏻᐃ┦ࢆᏳᐃ┦࡛࠶ࡿ ѸAl2O3 ࡬࡜㎿㏿࡟┦ኚែࡉࡏࡿࠊࡲࡓࡣ‽Ᏻᐃ Al2O3 ┦ࡢᙧᡂࢆᢚไࡍࡿᡭἲ
࡜ࡋ࡚ࠊ50nm ⛬ᗘࡢ Fe ࢼࣀࢥ࣮ࢸ࢕ࣥࢢἲࢆᥦ᱌ࡋ࡚࠸ࡿࠋⴭ⪅ࡽࡣࠊᨺᑕගࢆ⏝࠸ࡓ in-situᐃ࠿ࡽࠊࡑࡢ࣓࢝ࢽࢬ࣒ࡢᵓ⠏ࢆ㐍ࡵ࡚ࡁࡓ[1]ࠋࡇࢀࡲ࡛ࡢ ᐃ࠿ࡽࠊ㓟໬ࡢࡈࡃึᮇ࡟ࢥࣛࣥࢲ࣒ᵓ㐀ࡢ Fe2O3 ࡀ⏕ᡂࡋࠊࡇࡢึᮇ⏕ᡂ Fe2O3 ࠿ࡽ ѸAl2O3 ┦ࡀ┤᥋ᯒฟ࣓࢝ࢽࢬ࣒ࢆ᫂ࡽ࠿
࡟ࡍࡿࡇ࡜ࡀฟ᮶ࡓ[2]ࠋࡇࡢ◊✲ᡂᯝࡣࠊ㧗㍤ᗘ X ⥺ᅇᢡ࡜ඃࢀࡓ᫬㛫ศゎ⬟ࢆ᭷ࡍࡿ஧ḟඖ᳨ฟჾ PILATUS ࡢ⤌ࡳྜࢃࡏ࡟ࡼࡾᚓࡽࢀࡓ⤖ᯝ࡛࠶ࡾࠊᮏᡭἲࡀึᮇ㓟໬⓶⭷⏕ᡂᶵᵓࡢゎ᫂࡟ᑐࡋ࡚ᴟࡵ࡚᭷ຠ࡛࠶ࡿࡇ࡜ࢆ♧ࡋ࡚࠾ࡾࠊ᪥ᮏᅜෆእ࠿ࡽ㧗࠸ホ౯ࢆᚓ࡚࠸ࡿࠋ୍᪉ࠊࡇࢀࡲ࡛ࡢ◊✲ࡼࡾ Ni ࡣ┦ኚែࢆ㐜ᘏࡉࡏࡿࡇ࡜ࡀศ࠿ࡗ࡚࠸ࡿࡀࠊࡑࡢ࣓࢝ࢽࢬ࣒ࡣ๓ᅇࡢ ᐃ࠿ࡽࡣ᫂ࡽ࠿࡟࡞ࡗ࡚࠸࡞࠸ࠋ ๓ᅇࡢᐇ㦂࡛ࡣࠊึᮇ࡟⏕ᡂࡍࡿ Fe2O3 ࡢᙳ㡪ࢆほᐹࡍࡿࡓࡵ࡟ࠊFe ࢥ࣮ࢸ࢕ࣥࢢࢆ᪋ࡋࡓヨᩱࢆ኱Ẽ୰࡛㧗 㓟໬ࡋࡓࠋ୍᪉ࠊ௒ᅇࡢᐇ㦂࡛ࡣࠊFe2O3 ࡟ࡼࡿ ѸAl2O3 ┦ࡢ┤᥋⏕ᡂ࣓࢝ࢽࢬ࣒ࡢࡉࡽ࡞ࡿ⿬௜ࡅࢆᚓࡿࡇ࡜ࢆ┠ⓗ࡜ࡋ࡚ࠊྠ୍ࢧࣥࣉࣝࢆ Fe2O3 ࡀ⏕ᡂࡋ࡞࠸ప㓟⣲ศᅽୗ࡛㓟໬ࡋࡓ㝿ࡢࢫࢣ࣮ࣝ⏕ᡂᣲືࢆ᳨ウࡋࡓࠋࡲࡓࠊᮏᐇ㦂࠿ࡽࠊNi ࡢ┦ኚែ㐜ᘏຠᯝࢆ⪃ᐹࡍࡿࡇ࡜ࢆヨࡳࡓࠋ௒ᅇࡢᐇ㦂࡛ࡶࠊ㧗 ࢫࢸ࣮ࢪ࠾ࡼࡧ஧ḟඖ᳨ฟჾ PILATUS ࢆ⏝࠸࡚᪼ ᮇ㛫ࢆྵࡴ㧗 㓟໬୰ࡢᩓ஘ἲ࡟ࡼࡿ in situ ᐃࢆᐇ᪋ࡋࡓࠋ ᮏᐇ㦂࡟࠾ࡅࡿ┠ⓗࡣࠊ㻔1㻕ప㓟⣲ศᅽୗ࡟࠾࠸࡚ Fe ࢥ࣮ࢸ࢕ࣥࢢヨᩱୖ࡟⏕ᡂࡍࡿ Al2O3 ࢫࢣ࣮ࣝࡢ⏕ᡂ࠾ࡼࡧ┦ኚែᣲືࢆ᳨ウࡍࡿࡇ࡜ࠊ㻔2㻕Ni ࢥ࣮ࢸ࢕ࣥࢢ࡟ࡼࡿ┦ኚែ㐜ᘏຠᯝࢆ᳨ウࡍࡿࡇ࡜࡛࠶ࡿࠋᐇ㦂㸸 ᮏ ᐃࡣࠊࣅ࣮࣒ࣛ࢖ࣥBL19B2࡛ᐇ᪋ࡋࠊX⥺ࡢ࢚ࢿࣝࢠ࣮ࡣ12.39 keV㻔=1.0008 Å㻕ࢆ⏝࠸ࡓࠋࣅ࣮࣒ࣛ࢖ࣥ࡟タ⨨ࡉࢀࡓከ㍈ࢦࢽ࣓࣮࢜ࢱ࣮㸦HUVER♫〇㸧࡟㧗 ࢫࢸ࣮ࢪ㻔ANTON PARR♫〇HTK10㻕ࢆ⤌ࡳྜࢃࡏࠊヨᩱ࡬ࡢධᑕゅ=12.5°࡜ࡋࡓࠋᅇᢡ㹖⥺ࡣ஧ḟඖ᳨ฟჾPILATUS 100K
ࢆ୰ᚰゅᗘ2=25°࡛タ⨨ࡋࠊ࣓࢝ࣛ㛗ࢆ416.02mm࡜ࡋ࡚஧ḟඖ᳨ฟࡋࡓࠋ ᐃヨᩱࡣNi-50at%Al,
Fe-50at%Alྜ㔠࡟ࡑࢀࡒࢀFeࡲࡓࡣNiࢆ⣙70nmࡢཌࡉ࡛ࢥ࣮ࢸ࢕ࣥࢢࡋࡓヨᩱࢆ⏝࠸ࡓࠋヨᩱࡣࠊ㧗 ࢫࢸ࣮ࢪࡢⓑ㔠ࣄ࣮ࢱ࣮ୖ࡟タ⨨ࡋ࡚ࠊ኱Ẽ୰ࡲࡓࡣAr-0.9%H2-7.6%H2O 㻔PO2=1.810-13 atm,
FeO/Fe3O4ࡢᖹ⾮㓟⣲ศᅽ௨ୗ㻕ࡢప㓟⣲ศᅽ୰ࠊᐊ ࠿ࡽ50 K min-1࡛1000Υࡲࡓࡣ1100Υࡲ࡛᪼ࡋࠊࡑࡢᚋ᭱኱1᫬㛫ࡢ➼ 㓟໬ࢆ⾜ࡗࡓࠋ ᐃࡣ᪼ 㐣⛬ࡼࡾ10sẖ࡟⣙10s㛫⾜ࡗࡓࠋᚓࡽࢀ
ࡓ஧ḟඖ⏬ീࡣࠊImage Jࢆ⏝࠸࡚࿘᪉ྥ࡟ᩘ್✚ศࡋ୍ḟඖᅇᢡᅗࢆᚓࡓࠋ⤖ᯝ࠾ࡼࡧ⪃ᐹ㸸 ᅗ 1 ࡟ Fe ࢥ࣮ࢸ࢕ࣥࢢࢆ᪋ࡋࡓ Fe-50Al ྜ㔠ࡢ኱Ẽ୰࠾ࡼࡧ H2/H2O ΰྜ࢞ࢫ㸦ప㓟⣲ศᅽ㸧୰ࠊ᪼ ࠾ࡼࡧ 1100Υ࡟࠾ࡅࡿ➼ 㓟໬᫬㸦1 ᫬㛫㸧࡟ᚓࡽࢀࡓᅇᢡࣃࢱ࣮ࣥࢆࠊᅗ 2 ࡟ H2/H2Oΰྜ࢞ࢫ୰࡛⏕ᡂࡋࡓ㓟໬≀ࡢ X ⥺ᅇᢡᙉᗘࡢ᫬㛫ኚ໬ࢆ♧ࡍࠋ኱Ẽ୰࡛ࡢ㓟໬࡛ࡣࠊ᪼ ୰࡟ࢥࣛࣥࢲ࣒ᵓ㐀ࡢ Fe2O3 ࡢࣆ࣮ࢡࡀ☜ㄆࡉࢀࡿ࡜࡜ࡶ࡟ࠊ1000Υ㏆ഐࡼࡾ -Al2O3 ┦࠿ࡽࡢ᫂░࡞ࢲࣈࣝࣆ࣮ࢡࡀㄆࡵࡽࢀࡿࠋࡇࡢ⤖ᯝࡣࠊ๓ᅇࡢ ᐃ⤖ᯝ࡜඲ࡃྠࡌ࡛࠶ࡿࠋ୍᪉ࠊH2㸭H2O ΰྜ࢞ࢫ୰࡛ࡢ㓟໬≀ࡢ⏕ᡂᣲືࡣᴟࡵ࡚」㞧࡛࠶ࡿࠋప㓟⣲ศᅽୗ࡛ࡣࠊ᪼ 㐣⛬୰࡟ඛࡎ Fe3O4ࡀ⏕ᡂࡋࠊࡑࡢᚋ 570Υࢆ㉸࠼ࡓ᫬Ⅼ࡛ FeO ࡀ⏕ᡂࡋࡓࠋFeO ࡀ⏕ᡂࡋࡓ㝿࡟ࡣࠊFe3O4 ࡢࣆ࣮ࢡࡣㄆࡵࡽࢀ࡞ࡃ࡞ࡿࡀࠊࡑࡢᚋࠊFeO ࡢࣆ࣮ࢡࡣᾘ⁛ࡍࡿ࡜࡜ࡶ࡟ࠊ෌ࡧ Fe3O4 ࡢࣆ࣮ࢡࡀほᐹࡉࢀࡿࠋ᪼ ࡢᚋᮇ࡟ࡣࠊFe3O4 ࡢࣆ࣮ࢡᙉᗘࡀపୗࡋ࡚ࠊḟ࡟ FeAl2O4 ࡢ⏕ᡂࡀ☜ㄆࡉࢀࡓࠋ
FeAl2O4 ࡣ┤ࡕ࡟ᾘ⁛ࡋࠊࡑࡢᚋ -Al2O3 ࡢࣆ࣮ࢡࡀほᐹࡉࢀࡿࠋ ᗘࡀ 1100Υ࡟฿㐩ࡍࡿ࡜ࠊ
-Al2O3 ┦ࡀほᐹࡉࢀጞࡵࠊࡑࢀ࡟కࡗ࡚ -Al2O3 ࡢࣆ࣮ࢡࡣᾘ⁛ࡋࠊ௦ࢃࡗ࡚ FeAl2O4 ┦ࡀ෌ࡧ⌧ࢀࡿࡇ࡜ࡀศ࠿ࡿࠋࡲࡓࠊప㓟⣲ศᅽୗ࡛⏕ᡂࡋࡓ -Al2O3 ┦ࡢࣆ࣮ࢡࡣ኱Ẽ୰ࡢሙྜ࡜␗࡞ࡾࠊ୍ᮏࡢࢩ࣮ࣕࣉ࡞ࣆ࣮ࢡ࡛ᵓᡂࡉࢀ࡚࠸ࡿࡇ࡜ࡀศ࠿ࡗࡓࠋ ࡞࠾ࠊ௒ᅇ⏝࠸ࡓ H2/H2O ΰྜ࢞ࢫ୰ࡢ㓟⣲ศᅽࡣࠊᖹ⾮ィ⟬࡟ᇶ࡙ࡃሙྜࠊFeO ࡢࡳࡢᏑᅾ㡿ᇦ࡛࠶ࡿࡀᐇ㝿ࡢᐇ㦂࡛ࡣ Fe3O4 ࡀ⏕ᡂࡋࡓࠋࡇࢀࡣ⏝࠸ࡓ࢞ࢫ୰࡟ྵࡲࢀࡿ୙⣧≀㓟⣲ࡢᙳ㡪࡛࠶ࡿ࡜ᛮࢃࢀࡿࡀࠊ௒ᅇࡢ┠ⓗ࡛࠶ࡿ Fe2O3 ࡀ⏕ᡂࡋ࡞࠸㓟⣲ศᅽࡣ㐩ᡂࡉࢀ࡚࠾ࡾࠊᮏᐇ㦂ࡢ┠ⓗࡣ㐩ᡂ࡛ࡁࡓ࡜⪃࠼ࡽࢀࡿࠋᅗ 1 Fe ࢥ࣮ࢸ࢕ࣥࢢࢆ᪋ࡋࡓ Fe-Al ྜ㔠ࡢ኱Ẽ୰࠾ࡼࡧ H2/H2O ΰྜ࢞ࢫ୰ࠊ1100Υ࡟࠾ࡅࡿ㧗 㓟໬୰ࡢ㓟໬ࢫࢣ࣮ࣝ࠿ࡽࡢᅇᢡࣃࢱ࣮ࣥᅗ 2 Fe ࢥ࣮ࢸ࢕ࣥࢢࢆ᪋ࡋࡓ Fe-Al ྜ㔠ࡢ H2/H2O ΰྜ࢞ࢫ୰ࠊ1100Υ࡟࠾ࡅࡿ㧗࡟⏕ᡂࡋࡓ㓟໬≀ࡢᅇᢡᙉᗘࡢ᫬㛫ኚ໬㓟໬୰௒ᅇࡢᐇ㦂⤖ᯝ࡛ࡣࠊ㓟໬ึᮇ࡟ Fe2O3 ࡀ⏕ᡂࡋ࡞࠸ప㓟⣲ศᅽୗ࡛ࡢ㓟໬࡛ࡣࠊ-Al2O3 ࡀ┤᥋⏕ᡂࡏࡎࠊ㓟໬ึᮇ࡟ࡣ‽Ᏻᐃ -Al2O3 ࡀ⏕ᡂࡋࠊࡑࢀࡀ -Al2O3 ࡬࡜┦ኚែࡍࡿࡇ࡜ࡀ᫂ࡽ࠿
࡟࡞ࡗࡓࠋࡍ࡞ࢃࡕࠊFe ࢼࣀࢥ࣮ࢸ࢕ࣥࢢἲ࡟ࡼࡿ -Al2O3 ࡢ┤᥋⏕ᡂ࡟ࡣࠊFe2O3 ࡀ⏕ᡂࡋ࡚࠸ࡿࡇ࡜ࡀᚲせ࡛࠶ࡾࠊࡇࢀࡣⴭ⪅ࡽࡀᚑ᮶࠿ࡽᥦၐࡋ࡚࠸ࡿ -Al2O3 ࡜ྠ୍⤖ᬗᵓ㐀ࢆ᭷ࡍࡿ
Fe2O3 ࠿ࡽࡢᯒฟ࡛࠶ࡿࡇ࡜ࢆᙉࡃ♧ࡍ⤖ᯝ࡜࡞ࡗࡓࠋ
 ᅗ 3 ࡣࠊFe ࡲࡓࡣ Ni ࢥ࣮ࢸ࢕ࣥࢢࢆ᪋ࡋࡓヨᩱࢆ✀ࠎࡢ⎔ቃ୰࡛㓟໬ࡋࡓ㝿ࡢ  ࠿ࡽ -Al2O3࡬ࡢ┦ኚែ᫬㛫ࢆ♧ࡍࠋFe ࢥ࣮ࢸ࢕ࣥࢢࢆ᪋ࡋࡓヨᩱࡢప㓟⣲ศᅽୗ࡛ࡢ㓟໬࡛ࡣࠊ-Al2O3 ࡬ࡢ┦ኚែ㛤ጞ᫬㛫ࡣࠊ኱Ẽ୰࡛㓟໬ࡋࡓ↓ࢥ࣮ࢸ࢕ࣥࢢヨᩱୖ࡟ᙧᡂࡋࡓ Al2O3 ࡢ┦ኚែ㛤ጞ᫬㛫ࡼࡾࡶ㐜ᘏࡋࠊNi ࢥ࣮ࢸ࢕ࣥࢢᮦ࡜࡯ࡰྠࡌ࡜࡞ࡗ࡚࠸ࡿࡇ࡜ࡀࢃ࠿ࡿࠋᅗ 3 Fe ࡲࡓࡣ Ni ࢥ࣮ࢸ࢕ࣥࢢࢆ᪋ࡋࡓヨᩱࡢ  ࠿ࡽ -Al2O3 ࡢ┦ኚែ᫬㛫 ప㓟⣲ศᅽୗ࡛ࡢ㓟໬࡛ࡣࠊFe ࢥ࣮ࢸ࢕ࣥࢢᮦ⾲㠃࡟ࡣࠊFe ࡜ Al ࡢ」ྜ㓟໬≀࡛࠶ࡿࢫࣆࢿ
ࣝᆺ FeAl2O4 ࡀ⏕ᡂࡍࡿࡇ࡜ࡀ☜ㄆࡉࢀࡓࠋNi ࢥ࣮ࢸ࢕ࣥࢢᮦࢆ㓟໬ࡋࡓሙྜ࡛ࡶࠊ⾲㠃࡟ࡣ
NiAl2O4 ࡀ⏕ᡂࡍࡿࡇ࡜ࡀ๓ᅇ࠾ࡼࡧ௒ᅇࡢ ᐃ࠿ࡽ᫂ࡽ࠿࡟࡞ࡗ࡚࠾ࡾࠊࡇࢀࡽࡢ⤖ᯝࢆ⥲ྜࡍࡿ࡜ࠊࢫࣆࢿࣝ┦ࡢ⏕ᡂࡀࠊ ࠿ࡽ -Al2O3 ࡬ࡢ┦ኚែࢆ㐜ᘏࡉࡏ࡚࠸ࡿࡇ࡜ࡀண᝿ࡉࢀࡿࠋ⾲ 1࡟ࠊ௒ᅇࡢ ᐃ࡛ほᐹࡉࢀࡓ -Al2O3 ࡢᅇᢡ㠃ࢆ⧳ࡵ࡚♧ࡍࠋ௒ᅇࡢᐇ᪋ࡋࡓ 2 ᐃ⠊ᅖ࡛ࡣࠊ↓ࢥ࣮ࢸ࢕ࣥࢢヨᩱ࡜ Fe ࢥ࣮ࢸ࢕ࣥࢢヨᩱࡢ኱Ẽ୰࡛ࡣࠊ-Al2O3 ࡢ㻔401㻕࠾ࡼࡧ㻔002㻕࠿ࡽࡢᅇᢡ
ࣆ࣮ࢡࡀほᐹࡉࢀࡓࠋ୍᪉ࠊప㓟⣲ศᅽୗࡢ㓟໬࡛ࡣࠊ↓ࢥ࣮ࢸ࢕ࣥࢢヨᩱ࡛ࡣࠊࡇࢀࡽࡢࣆ࣮
ࢡ࡟ຍ࠼࡚㻔111㻕㠃࠿ࡽᅇᢡࡀࠊࡲࡓࠊFe ࢥ࣮ࢸ࢕ࣥࢢヨᩱࡢሙྜࡣࠊ㻔002㻕㠃࠿ࡽࡢᅇᢡࡣㄆࡵࡽ
ࢀࡎࠊ㻔400㻕, 㻔111㻕࠾ࡼࡧ㻔11-2㻕㠃࠿ࡽࡢࣆ࣮ࢡࡀほᐹࡉࢀࡓࠋࡉࡽ࡟ࠊ኱Ẽ୰࡛ Ni ࢥ࣮ࢸ࢕ࣥࢢᮦࢆ㓟໬ࡋࡓሙྜ࡟ࡶࠊ㻔111㻕࠾ࡼࡧ㻔11-2㻕㠃࠿ࡽࡢᅇᢡࡀほᐹࡉࢀ࡚࠸ࡿࠋప㓟⣲ศᅽୗ࡛ࡢ㓟໬ࠊ
ࡲࡓࡣ Ni ࢥ࣮ࢸ࢕ࣥࢢヨᩱ࡛ほᐹࡉࢀࡓࠊࡇࢀࡽ -Al2O3 ࡢ㻔400㻕, 㻔40-1㻕, 㻔111㻕, 㻔11-2㻕㠃ࡣࠊ⾲୰࡟♧ࡋࡓࡼ࠺࡟ࠊࢫࣆࢿࣝᵓ㐀ࡢ FeAl2O4 ࡲࡓࡣ NiAl2O4 ࡢ㻔022㻕, 㻔113㻕࠾ࡼࡧ㻔004㻕㠃࡟┦ᙜࡍࡿࠋࡇࢀࡣ -Al2O3 ࡜ࢫࣆࢿࣝᵓ㐀ࡣࠊ≉࡟㓟⣲ࡢ๪᱁Ꮚࡀᮏ㉁ⓗ࡟ࡣྠ୍ࡢ FCC ⛻ᐦᵓ㐀ࢆࡋ࡚࠸ࡿ
[3,4]ࡓࡵ࡛࠶ࡾࠊࡍ࡞ࢃࡕࠊ⇕ຊᏛⓗ࡟ࡶᏳᐃ┦࡛࠶ࡿࢫࣆࢿࣝᵓ㐀ࢆ᭷ࡍࡿ」ྜ㓟໬≀ࡀ⏕ᡂࡍࡿࡇ࡜࡟ࡼࡾࠊ‽Ᏻᐃ┦࡛࠶ࡿ -Al2O3 ࡢᵓ㐀ࡀᏳᐃ໬ࡉࢀࡓྍ⬟ᛶࡀ㧗࠸ࠋࡑࡢ⤖ᯝࠊࢫࣆࢿࣝ㓟໬≀ࡀ⏕ᡂࡋࡓሙྜ࡟ࠊ-Al2O3 ࡬ࡢ┦ኚែࡀ㐜ᘏࡋࡓ࡜⪃࠼ࡽࢀࡿࠋ
⾲1 ᐇ㦂࡛ほᐹࡉࢀࡓ-Al2O3ࡢᅇᢡ㠃࡜ࡑࢀࡽ࡟┦ᙜࡍࡿFeAl2O4࠾ࡼࡧNiAl2O4ࡢᅇᢡ㠃
㻔400㻕
㻔40-1㻕
㻔002㻕
㻔111㻕
㻔11-2㻕
-Al2O3 planes
FeAl2O4 planes
㻔022㻕
㻔113㻕
㻔004㻕
NiAl2O4 planes
㻔022㻕
No-coated FeAl኱Ẽ×
××
኱Ẽ+H2O×××
H2/H2O××
Fe-coated FeAl
H2/H2O×
Ni-coated FeAl኱Ẽ×௒ᚋࡢㄢ㢟㸸 ௒ᅇࡢ ᐃ࡛ࡣࠊFe2O3 ࡀ⏕ᡂࡋ࡞࠸ప㓟⣲ศᅽୗ࡟࠾ࡅࡿ Al2O3 ࢫࢣ࣮ࣝ⏕ᡂྜ㔠ୖࡢ Al2O3ࢫࢣ࣮ࣝࡢ┦ኚែᣲືࢆ᳨ウࡋ࡚ࠊⴭ⪅ࡽࡢᥦ᱌ࡍࡿ Fe2O3 ࠿ࡽࡢ -Al2O3 ࡢ┤᥋ᯒฟ࣓࢝ࢽࢬ࣒ࢆ᳨ドࡋࡓࠋࡲࡓࠊࡑࢀࡽ⤖ᯝࡼࡾ Ni ࡟ࡼࡿ  ࠿ࡽ -Al2O3 ࡬ࡢ┦ኚែ㐜ᘏຠᯝࢆ᳨ウࡋࡓࠋࡇࢀࡲ࡛ࡢⴭ⪅ࡽࡢᥦ᱌ᶵᵓࢆࡉࡽ࡟ᙉᅛ࡟⿬௜ࡅࡿ⤖ᯝࡀᚓࡽࢀࡓ࡜࡜ࡶ࡟ࠊNi ࡢ㐜ᘏຠᯝ࡟ᑐࡍࡿ୍ࡘࡢྍ⬟ᛶࢆᚓࡿࡇ࡜ࡀฟ᮶ࡓࠋ୍᪉ࠊ௒ᅇࡢᐇ㦂࡛ࡶࠊNi ࡢ Al2O3 ┦ኚែ㐜ᘏຠᯝ࡟ࡘ
࠸࡚ࡣ☜ドࢆᚓࡿࡇ࡜ࡀฟ᮶࡞࠿ࡗࡓࠋࡇࢀࡲ࡛ࡢ ᐃ࡛ࡣࠊ୺࡟Ᏻᐃ┦ -Al2O3 ࡢ㠃㛫㝸ኚ໬࡟╔┠ࡋ࡚ゎᯒࢆ㐍ࡵ࡚ࡁࡓࡀࠊ㐜ᘏຠᯝ࡟㛵ࡍࡿ᳨ウࢆࡉࡽ࡟㐍ࡵࡿࡓࡵ࡟ࡣࠊ௒ᚋࠊ-Al2O3ࡢ㠃㛫㝸ኚ໬࡜┦ኚែ࡟╔║Ⅼࢆ࠾࠸ࡓᐇ㦂ࢆᐇ᪋ࡍࡿᚲせࡀ࠶ࡿࠋ ࡲࡓࠊ௒ᅇࡢ H2/H2O ΰྜ࢞ࢫࢆ⏝࠸ࡓᐇ㦂࠿ࡽࠊࡇࢀࡲ࡛ⴭ⪅ࡽࡀ㐍ࡵ࡚ࡁࡓ In-situ ᐃᡭἲࢆࠊࡉࡽ࡟✀ࠎࡢไᚚ⎔ቃୗ࡛ࡶᐇ᪋࡛ࡁࡿయไࢆ☜❧ࡍࡿ஦ࡀฟ᮶ࡓࠋ௒ᚋࠊᵝࠎ࡞㧗 ⭉㣗࣭㓟໬ᐇ㦂࡬ࡢ㐺⏝ࡀᮇᚅ࡛ࡁࡿࠋ୍᪉ࠊ⌧ᅾࡢᐇ㦂タഛ࡛ࡣࠊձヨᩱࡢᐇ ᗘ ᐃࡀ୙ྍ⬟ࠊղ᪼ ࡟క࠺ヨᩱ⾲㠃ࡢ Z ᪉ྥ࡬ࡢࢻࣜࣇࢺࡀࢹ࣮ࢱ࡜ࡋ࡚ᚓࡽࢀ࡚࠸࡞࠸ࠊճࢫࢣ࣮ࣝࡢ⏕ᡂࠊᡂ㛗ࠊヨᩱࡢ᪼ ࠊ෭༷࡟కࡗ࡚Ⓨ⏕ࡍࡿ⇕ࡲࡓࡣṧ␃ᛂຊࢆཎᅉ࡜ࡍࡿ᱁Ꮚᐃᩘࡢኚ໬࡜ࢫࢣ࣮ࣝ୰࡬ࡢᚤ㔞ඖ⣲ᅛ⁐࡟ࡼࡿ᱁Ꮚᐃᩘࡢኚ໬ࢆศ㞳ฟ᮶࡞࠸ࠋࡇࢀࡽࡣࠊࡉࡽ࡞ࡿ㧗⢭ᗘࡢᐃ࡟㝿ࡋ࡚ࡣゎỴࡍ࡭ࡁㄢ㢟࡛࠶ࡿࠋཧ⪃ᩥ⊩㸸[1] Y. Kitajima, S. Hayashi, T. Nishimoto, T. Narita, and S. Ukai, Oxid. Met., 73, 㻔2010㻕, 375.
[2] S. Hayashi, I. Saeki, Y. Nishiyama, T. Doi, S. Kyo, and M. Segawa, Mater. Sci. Forum, 696, 㻔2011㻕, 63.
[3] I. Levin and D. Brandon, J. Am. Ceram. Soc., 81, 㻔1998㻕, 1995.
[4] R-S. Zhou and R.L. Snyder, Acta Cryst. B47, 㻔1991㻕, 617.