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Theoretical study on reaction analysis of Ru/TiO2 catalyst based on density
functional theory (DFT):
CO2 molecule in a bent form
T. Shimazaki,a S. Akamaru,b T. Abe,b and M. Kuboaa) Fracture and Reliability Research Institute, Graduate School of Engineering, Tohoku
University6-6-11 Aoba, Aramaki, Aoba-ku, Sendai 980-8579b) Hydrogen Isotope Research Center, University of Toyama
3190 Gofuku, Toyama 930-8555(Received January 10, 2012; accepted March 8, 2012)
Abstract
The Ru/TiO2 catalyst holds great promise as a key material for artificial conversion of CO2 to CH4 throughseveral hydrogenation elementary reactions. In this study, we examined the bent structure of CO2 moleculeson the Ru(0001) surface and Ru-nano-clusters to investigate the Ru/TiO2 catalytic reaction, based on thedensity functional theory (DFT) at the generalized gradient approximation (GGA) level under the periodic
boundary condition. The bent structure of CO2 can trigger a series of hydrogenation reactions leading to theformation of CH4, and this structure can be observed not only on the Ru(0001) surface and the Ru
nano-particles on the TiO2(101) surface but also on the homogeneous Ru complex catalyst. These findings
suggest that the bending of the CO2 molecule on Ru metal is a key process to activate the stable CO2molecule.

1, ✜⸒࿕૕⸅ᇦࠍ↪޿ߚ CO2 ࡔ࠲ࡦൻ෻ᔕߪᏱ࿶ਅߢ෻ᔕ߇น⢻ߢ޽ࠆߎߣ߆ࠄ‫ޔ‬࿾⃿᷷ᥦൻߩਥⷐ°°࿃ߣ⋡ߐࠇߡ޿ࠆ CO2 ߩ࿕ቯൻߦ೑↪ߢ߈ࠆ‫ߩߎߒ߆ߒޕ‬෻ᔕߪㅢᏱ 300 C 㨪400 C ߩ▸࿐ߢⴕࠊࠇࠆ‫ޕ‬CO2 ߩࡔ࠲ࡦൻ෻ᔕߦ㜞ࠛࡀ࡞ࠡ࡯ࠍ೑↪ߔࠆߎߣߪ‫ޔ‬CO2 ߩ࿕ቯൻߩ⋡⊛ߣ෻ߔࠆߚ
߼‫ߩߎޔ‬෻ᔕ᷷ᐲߩૐ᷷ൻ߇น⢻ߣߥࠆ⸅ᇦߩ㐿⊒߇ᔅⷐߢ޽ࠆ‫ޕ‬ㄭᐕ‫☳ߩߢࠬ࠮ࡠࡊࠗ࡜࠼ޔ‬૕ᓸ☸ሶߩ⴫㕙ୃ㘼ᴺߢ޽ࠆ‫ޟ‬ᄙⷺࡃ࡟࡞ࠬࡄ࠶࠲࡝ࡦࠣᴺ‫ࠍޠ‬೑↪ߒߡ⺞⵾ߒߚ Ru ࠽ࡁ㊄ዻᜂᜬ TiO2 ⸅ᇦ㧔BS ⸅ᇦ㧕߇ᵈ⋡ߐࠇߡ޿ࠆ 1‫ޕ‬ᄙⷺࡃ࡟࡞ࠬࡄ࠶࠲࡝ࡦࠣᴺߢᓧࠄࠇࠆ࠽ࡁ☸ሶߪဋ৻ߥ☸ሶᓘಽᏓࠍ᦭ߒ‫ ߟ߆ޔ‬Ru ࠽ࡁ㊄ዻ߇㜞ಽᢔߦᜂᜬߐࠇࠆ‫ߡߒߦ߁ࠃߩߎޕ‬ᓧࠄࠇߚ࿕૕
°°⸅ᇦߪ‫ޔ‬೨ಣℂߥߒߦᭂ߼ߡૐ᷷㧔⚂ 60 C 㧕ߢ CO2 ᳓⚛ൻ෻ᔕ߇ㅴⴕߒᆎ߼‫ ⚂ޔ‬160 C ߢォൻ₸‫ޔ‬ㆬᛯ₸౒ߦ 100%ߩ⸅ᇦᵴᕈࠍ␜ߔ╬‫ޔ‬ᓥ᧪ߩ⸅ᇦߣᲧߴߡఝࠇߚ․ᕈࠍ␜ߔߎߣ߇ႎ๔ߐࠇ
ߡ޿ࠆ 1‫⸅ޔߦࠄߐޕ‬ᇦᵴᕈߪᜂᜬߐࠇߚ Ru ߩ☸ᓘᷫዋߣ౒ߦჇᄢߔࠆߎߣ߆ࠄ‫ޔ‬Ru ߩ࠽ࡁ☸ሶൻߣ⸅ᇦᵴᕈߩ㑐ㅪᕈ߇⼏⺰ߐࠇߡ޿ࠆ‫⃻ޔߒ߆ߒޕ‬࿷߹ߢ Ru ࠽ࡁ☸ሶߢߩ⹦⚦ߥ෻ᔕᯏ᭴ߪ᣿ࠄ߆ߦߐࠇߡ޿ߥ޿‫ޔߢߎߘޕ‬BS ⸅ᇦߩ㜞ᵴᕈ࿃ሶߦߟ޿ߡኒᐲ᳢㑐ᢙℂ⺰(DFT)ߦၮߠ޿ߚ╙৻ේℂ⸘▚ࠪࡒࡘ࡟࡯࡚ࠪࡦࠍ↪޿ߡ Ru ⸅ᇦߩ෻ᔕᯏ᭴ߩ⸃᣿ࠍ⹜ߺߚ‫ߣ࠻࠶ࠥ࡯࠲ޔߢߎߎޕ‬ߒߡ޿ࠆ CO2 ಽሶߪൻቇ⊛ߦ቟ቯߢ޽ࠅ‫ޔ‬ਇᵴᕈߥಽሶߢ޽ࠆ‫ߥ߁ࠃߩߎޕ‬ਇᵴᕈಽሶߦኻߒߡ‫ޔ‬࿕૕⸅ᇦ਄ߢߤߩࠃ߁ߥൻቇ෻ᔕᯏ᭴߇ㅴⴕߔࠆߩ߆ࠍ᣿ࠄ߆ߦߔࠆߎߣߪ‫ޔ‬BS ⸅ᇦߩߺߥࠄߕ‫ޔ‬࿕૕⸅ᇦߩၮ␆ቇℂࠍ⊒ዷߐߖࠆ਄ߢ߽᦭⋉ߢ޽ࠆ‫⎇ᧄޔߢߎߘޕ‬ⓥߢߪ‫ޔ‬CO2 ಽሶߩๆ⌕᭴ㅧ
ߦ․ߦᵈ⋡ߒߚ‫ޕ‬CO2 ಽሶߩ࿕૕⸅ᇦ਄߳ߩๆ⌕ߪ‫ޔ‬CO2 ࡔ࠲ࡦൻ෻ᔕߩ⚛෻ᔕߩ╙৻ࠬ࠹࠶ࡊߣߒߡ⠨߃ࠄࠇ‫ోޔ‬෻ᔕࠨࠗࠢ࡞ߩਛߢ߽ᭂ߼ߡ㊀ⷐߥᗧ๧ࠍᜬߟߚ߼ߢ޽ࠆ 2‫ࠪޔߪߢ┨ߊ⛯ޕ‬ࡒࡘ࡟࡯࡚ࠪࡦᚻᴺࠍ⸥ㅀߒߚᓟߦ⚿ᨐ߅ࠃ߮⠨ኤࠍឭ␜ߔࠆ‫ޕ‬2, ⸘▚ᣇᴺ ᧄ⎇ⓥߢߪ‫ޔ‬๟ᦼႺ⇇᧦ઙਅߢߩኒᐲ᳢㑐ᢙ(DFT)⸘▚ࠍⴕߞߚ‫ޕ‬DFT ⸘▚ߦߪ‫ޔ‬DMol3 ࡊࡠࠣ࡜ࡓ࡮ࡄ࠶ࠤ࡯ࠫࠍណ↪ߒߚ 3‫ޕ‬Perdew‫ޔ‬Burke‫ޔ‬Ernzerhof ߦࠃߞߡឭ᩺ߐࠇߚ৻⥸ൻ൨㈩ㄭૃ
(GGA)ߦࠃࠆ PBE ᳢㑐ᢙࠍ↪޿ 4‫ޔ‬ၮᐩ㑐ᢙߦߪ double-numerical basis-set with polarization (DNP)ࠍ૶↪ߒߚ 3‫ޔߚ߹ޕ‬ౝᩭ㔚ሶߪ Effective core potential (ECP) ߦࠃࠅ⸥ㅀߒߚ 3‫⺰ᧄޕ‬ᢥߢ␜ߔ‫ޔ‬Ru ࡃ࡞ࠢ⴫㕙ࡕ࠺࡞ߢߪ‫ޔ‬3×3×1 ߩ k ὐࠨࡦࡊ࡝ࡦࠣࠍ↪޿‫ޔ‬㐳〒㔌ࡂ࡯࠻࡝࡯㗄ߩ⸘▚ߩ㜞ㅦൻߩߚ߼ߦ octupole ߩᄙᭂሶዷ㐿ࠍ૶↪ߒ‫ޔ‬4.7 Å ߩ global-cutoff‫ޔ‬0.01 Hartree ߩ smearing ࡄ࡜ࡔ࡯࠲ࠍ↪޿ߚ‫㉄ޔߚ߹ޕ‬ൻ࠴࠲ࡦ਄ߦᒻᚑߒߚ Ru ࠢ࡜ࠬ࠲࡯࡮ࡕ࠺࡞ߢߪ‫ޔ‬2×2×1 ߩ k ὐࠨࡦࡊ࡝ࡦࠣࠍ↪޿‫ޔ‬5.2 Å ߩ global-cutoff ࠍ↪޿ߚ‫ޕ‬

3, ⚿ᨐߥࠄ߮ߦ⠨ኤ
3.1 Ru(0001)਄ߩ CO2 ๆ⌕᭴ㅧ BS ⸅ᇦ਄ߢߪ࠽ࡁࠨࠗ࠭ߩ Ru ࠢ࡜ࠬ࠲࡯߇㉄ൻ࠴࠲ࡦ਄ߦᜂᜬߐࠇ‫ޔ‬㜞޿⸅ᇦᵴᕈࠍ␜ߒߡ޿ࠆ߇‫⸅ޔ‬ᇦ෻ᔕߩᵴᕈਛᔃߣ⠨߃ࠄࠇࠆ Ru ㊄ዻߩᓎഀࠍ᣿ࠄ߆ߦߔࠆߎߣߪ‫ⶄޔ‬㔀ߥ࿕૕⸅ᇦ෻ᔕᯏ᭴ࠍ⸃᣿ߔࠆߚ߼ߩ╙৻ᱠߢ޽ࠆߣ⸒߃ࠆ‫⎇ᧄޔߢߎߘޕ‬ⓥߢߪ‫߼ߚߩ⊛⋡ߥ߁ࠃߩߎޔ‬ߦ Ru(0001)㕙਄ߩ CO2 ಽሶߩๆ⌕᭴ㅧߦߟ޿ߡ߹ߕߪ⼏⺰ࠍⴕ߁‫ޕ‬࿑ 1 ߦ␜ߒߚࠃ߁ߦ‫ޔ‬Ru(0001)
㕙਄ߩࡕ࠺࡞ߣߒߡ 4 ጀߩ㊄ዻ࡟ࠗࡗ࡯߆ࠄߥࠆࠬ࡜ࡉࡕ࠺࡞ࠍ↪޿ߚ‫࡞࠺ࡕࡉ࡜ࠬޔߡߒߘޕ‬਄ߦ CO2 ಽሶࠍ⟎߈‫ޔ‬㊄ዻጀ਄ߩ CO2 ಽሶߩๆ⌕ࠨࠗ࠻ߩត⚝ࠍⴕߞߚߣߎࠈ‫ޔ‬࿑ 1a ߅ࠃ߮࿑1b ߦ⷗ࠄࠇࠆࠃ߁ߥ᭴ㅧ߇ᓧࠄࠇߚ‫ޕ‬࿑ 1a ߢߪ‫ޔ‬CO2 ಽሶߪਇᵴᕈಽሶߢ޽ࠆߎߣ߆ࠄ Ru ㊄ዻጀߣᒝߊ⋧੕૞↪ࠍߔࠆߎߣߥߊๆ⌕ߔࠆ‫ޔߒ߆ߒޕ‬࿑ 1b ߢߪਇᵴᕈߥ CO2 ಽሶߪࡌࡦ࠼ߒߥ߇
ࠄ Ru ⴫㕙਄ߦๆ⌕ߔࠆ‫ޔ߈ߣߩߎޕ‬CO2 ಽሶߪ hollow-site ߆ࠄ௖߆ߦߕࠇߚ૏⟎ߦๆ⌕ߒ‫߽ᦨޔ‬ㄭ޿ Ru ේሶߣ὇⚛ේሶ㑆ߩ〒㔌ߪ‫ޔ‬2.06 Å ߢ޽ࠅ‫ޔ‬CO2 ಽሶౝߩ὇⚛-㉄⚛㑆ߩ〒㔌ߪߘࠇߙࠇ‫ޔ‬
1.21 Å ߅ࠃ߮ 1.37Å ߢ޽ࠆ‫ޔߚ߹ޕ‬O-C-O ⷺᐲߪ‫ޔ‬125.1 ᐲߢ޽ࠆ‫ ߥ߁ࠃߩߎޕ‬CO2 ಽሶߩࡌࡦ
࠼ߒߚ᭴ㅧ߇⷗ࠄࠇࠆߩߪ‫ޔ‬Ru ㊄ዻ⴫㕙ߩ㔚ሶ⁁ᘒߩᓇ㗀ࠍฃߌߡ޿ࠆߚ߼ߢ޽ࠆ‫ޔߚ߹ޕ‬Ru㊄ዻ⴫㕙਄ߢߩ CO2 ࡔ࠲ࡦൻ෻ᔕߪ‫ ߥ߁ࠃߩߎޔ‬CO2 ಽሶ߇ࡌࡦ࠼ߒߡๆ⌕ߔࠆࠃ߁ߥࡊࡠ࠮ࠬ
ࠍ⚻ߡㅴⴕߔࠆ 2‫ޕ‬࿑ 1a ߆ࠄ࿑ 1b ߳ߩ CO2 ಽሶ߳ߩๆ⌕᭴ㅧߦߟ޿ߡ‫ޔ‬Quadratic SynchronousTransit (QST) optimization ᴺ 5 ࠍ↪޿ߡㆫ⒖⁁ᘒត⚝߅ࠃ߮෻ᔕ⸃ᨆࠍⴕߞߚߣߎࠈ‫ޔ‬෻ᔕࠛࡀ࡞
ࠡ࡯ߪ -0.58 kcal/mol ߢ޽ࠅ‫ߡߒߘޔ‬ᵴᕈൻࡃ࡝ࠕߪ 5.5 kcal/mol ߢ޽ࠆߎߣ߇ಽ߆ߞߚ‫ࠃߩߎޕ‬߁ߦ‫ޔ‬ૐ෻ᔕࠛࡀ࡞ࠡ࡯‫ޔ‬ૐᵴᕈൻࡃ࡝ࠕߢ޽ࠆߎߣ߆ࠄ‫ޔ‬࿑ 1a ߅ࠃ߮࿑ 1b ߢ⷗ࠄࠇࠆࠃ߁ߥ
CO2 ಽሶߩๆ⌕᭴ㅧㆫ⒖ߪ‫ޔ‬Ru ㊄ዻ⴫㕙਄ߢ㗫❥ߦ⿠ߎߞߡ޿ࠆߣ⠨߃ࠄࠇࠆ‫ޕ‬

࿑ 1 Ru(0001)㕙਄ߩ CO2 ಽሶߩๆ⌕᭴ㅧ‫ޕ‬࿑ਛߩ a)߅ࠃ߮ b)ߪߘࠇߙࠇ᭴ㅧᦨㆡൻ⸘▚ࠍⴕߞߡᓧࠄࠇߚ᭴ㅧ‫ޕ‬࿑ 1b ߦ⷗ࠄࠇࠆࠃ߁ߦ‫ޔ‬CO2 ಽሶ߇ࡌࡦ࠼ߒߡๆ⌕ߔࠆߎߣߦࠃࠅ‫ޔ‬᳓⚛ൻ෻ᔕߩ࠻࡝ࠟ࡯ߣߥࠆ‫ޕ‬৻ᣇ‫ޔ‬࿑ 1b ߦ⷗ࠄࠇࠆࡌࡦ࠼ߒߚ CO2 ಽሶ߳ߩ㉄⚛ේሶߦኻߔࠆ᳓⚛ේሶߩઃട෻ᔕߢߪ‫ޔ‬෻ᔕࠛࡀ࡞ࠡ࡯ߪ -2.9 kcal/mol ߣ⊒ᾲ෻ᔕߢ޽ࠆ߽ߩߩ‫ޔ‬ᵴᕈൻࡃ࡝ࠕߪ 22.3 kcal/mol ߣ㕖Ᏹߦ㜞޿ߎߣ߇ DFT ⸘▚ࠃࠅಽ߆ߞߚ 2‫ޔߡߞࠃޕ‬CO2 ಽሶߩ Ru ਄ߢࡌࡦ࠼ๆ⌕ᓟߦ⛯޿ߡ⿠ߎࠆ᳓⚛ൻ෻ᔕߪ‫ޔ‬CO2 ࡔ࠲ࡦൻ෻ᔕో૕ࠍᓞߔࠆ⚛෻ᔕߩ 1 ߟߢ޽ࠆ‫ޕ‬

3.2 Ru ࠢ࡜ࠬ࠲࡯/TiO2 ਄ߩ CO2 ๆ⌕᭴ㅧ ታ㓙ߩ BS ⸅ᇦߪ‫㉄ߩ╬࠽ࡒ࡞ࠕ߿ࠕ࠾࠲࠴ޔ‬ൻ‛ߩ਄ߦ Ru ࠽ࡁ࡮ࠢ࡜ࠬ࠲࡯߇ᜂᜬߐࠇ↪޿ࠄࠇࠆ‫ޕ‬ട߃ߡ‫ޔ‬ਅ࿾ߣߒߡ↪޿ࠄࠇߡ޿ࠆ㉄ൻ‛ߩᓇ㗀ߦࠃࠅ‫⸅ޔ‬ᇦ․ᕈ߇Ꮐฝߐࠇࠆߣ޿߁
ታ㛎⚿ᨐ߽޽ࠆ‫㉄ޕ‬ൻ‛ߦࠃࠆਅ࿾ലᨐߩේሶ࡮ಽሶ࡟ࡌ࡞ߢߩࡔࠞ࠾࠭ࡓߩ⹦⚦ߪਇ᣿ߢ޽ࠆ
߇‫ߩߘޔ‬ᓇ㗀ࠍ⸃᣿ߔࠆߚ߼ߦ‫ޔ‬࿑ 2 ߦ␜ߔࠃ߁ߥ TiO2(101)਄ߦ Ru ㊄ዻේሶ 10 ୘߆ࠄߥࠆࠢ࡜
ࠬ࠲࡯ࠍ⟎޿ߚࡕ࠺࡞ࠍ૞ᚑߒߚ‫㉄ޔߢߎߎޕ‬ൻ࠴࠲ࡦߪᦨ቟ቯ㕙ߢ޽ࠆ(101)㕙ࠍណ↪ߒߚ‫߹ޕ‬ߚ‫ޔ‬TiO2(101)ㇱಽߪ࿕ቯൻߒ‫ޔ‬Ru ࠢ࡜ࠬ࠲࡯ㇱಽߪ᭴ㅧᦨㆡൻࠍⴕߞߚ‫ߡߒߦ߁ࠃߩߎޕ‬ᓧࠄࠇߚ Ru ࠢ࡜ࠬ࠲࡯/TiO2 ਄ߢߩ CO2 ๆ⌕㧔ᦨㆡൻ㧕᭴ㅧࠍ࿑ 2a ߅ࠃ߮࿑ 2b ߦ␜ߔ㧔࿑ 2a ߪ side-viewߢ޽ࠅ‫ޔ‬࿑ 2b ߪ top-view㧕‫ޔߚ߹ޕ‬CO2 ๆ⌕㧔ᦨㆡൻ㧕᭴ㅧࠍᓧࠆߚ߼ߦ‫㉄ޔ‬ൻ࠴࠲ࡦ߅ࠃ߮ Ru࠽ࡁ࡮ࠢ࡜ࠬ࠲࡯᭴ㅧߪ࿕ቯߒߡ⸘▚ࠍⴕߞߚ‫ޕ‬
࿑ 2 ߢ␜ߒߚ CO2 ಽሶਛߩ὇⚛ේሶߣ㊄ዻࠢ࡜ࠬ࠲࡯ਛߩᦨ߽ㄭ޿ Ru ේሶߣߩ〒㔌ߪ 2.03 Åߢ޽ࠅ‫ޔ‬὇⚛ߣ㉄⚛ේሶ㑆ߩ〒㔌ߪ‫ ࠇߙࠇߘޔ‬1.30 Å ߅ࠃ߮ 1.22 Å ߢ޽ࠆ‫ ߚ߹ޕ‬O-C-O ⷺᐲߪ132.19 ᐲߢ޽ࠆ‫ޔߦ߁ࠃߩߎޕ‬Ru ࠢ࡜ࠬ࠲࡯/ TiO2 ਄ߢ߽ CO2 ߩๆ⌕᭴ㅧߪࡃ࡞ࠢ Ru ⴫㕙ߣห᭽ߦࡌࡦ࠼ߔࠆ‫ޕ‬Ru ࠢ࡜ࠬ࠲࡯/ TiO2 ਄ߦๆ⌕ߒߚ CO2 ಽሶౝߩ὇⚛-㉄⚛〒㔌ߪ‫ޔ‬Ru ⴫㕙਄ߩ
CO2 ಽሶౝߦᲧߴࠆߣ௖߆ߦ⍴ߊߥߞߡ޿ࠆ߽ߩߩ‫ⷺࠆߔ࠼ࡦࡌޔ‬ᐲߪ௖߆ߦᄢ߈ߊߥߞߡ޿ࠆ‫ޕ‬ߎߎߢ‫⌀ޔ‬ⓨਛߦ⟎߆ࠇߚ CO2 ಽሶౝߩ C-O 〒㔌ߪ 1.18 Å ߢ޽ࠆ‫ߩࠇߕ޿ޕ‬႐ว߽‫࠼ࡦࡌޔ‬ๆ⌕᭴ㅧࠍขࠆߎߣߦࠃߞߡ‫ޔ‬C-O 〒㔌ߪિ߮ࠆߎߣ߇⏕⹺ߐࠇߚ‫ ߥ߁ࠃߩߎޕ‬CO2 ߩࡌࡦ࠼᭴ㅧߪ‫ޔ‬ࡃ࡞ࠢ⴫㕙ߣห᭽ߦ‫ޔ‬Ru ࠢ࡜ࠬ࠲࡯/TiO2 ਄ߩ CO2 ࡔ࠲ࡦൻ෻ᔕߩೋᦼ᭴ㅧߣߒߡ㊀ⷐߢ޽ࠆߣ⠨߃ࠄࠇࠆ‫ޔߦ․ޕ‬CO2 ߩࡌࡦ࠼ๆ⌕ߦ⛯ߊ᳓⚛ൻ෻ᔕߪ‫ࡦ࠲ࡔޔ‬ൻ෻ᔕో૕ࠍᓞߔࠆ෻ᔕߩ㧝ߟߢ޽ࠆߎߣ߇್᣿ߒߡ߅ࠅ 2‫ޔ‬
Ru ࠢ࡜ࠬ࠲࡯/TiO2 ߩ♽ߢ߽ห᭽ߦ෻ᔕ߇ㅴⴕߔࠆߣ⠨߃ࠄࠇࠆ‫ޕ‬

࿑ 2 TiO2(101)⴫㕙ߢߩ࠽ࡁࠨࠗ࠭ߩ Ru ࠢ࡜ࠬ࠲࡯࡮ࡕ࠺࡞‫ޕ‬a) ߪ side-view‫ޔ‬b) ߪ top-view‫ޕ‬Ru ࠢ࡜ࠬ࠲࡯࡮ࡕ࠺࡞਄ߢ CO2 ಽሶߪࡌࡦ࠼ߒߡๆ⌕ߔࠆ‫ޕ‬৻ᣇ‫ޔ‬ab-initio ㊂ሶൻቇࠍ↪޿ߡ‫ޔ‬ဋ৻⸅ᇦߢ޽ࠆ Ru ㍲૕ߦࠃࠆ CO2 ಽሶ߆ࠄࠡ㉄߳ߩㆶర෻
ᔕ⸃ᨆ߇ႎ๔ߐࠇߡ޿ࠆ 6‫ޕ‬Ru ㍲૕ߩࠃ߁ߥဋ৻⸅ᇦߢ޽ߞߡ߽ CO2 ಽሶߩㆶర෻ᔕߢߪ࿑㧝߅
ࠃ߮࿑ 2 ߢ⷗ࠄࠇߚࠃ߁ߥ CO2 ಽሶߩࡌࡦ࠼߇ⷰኤߐࠇߡ޿ࠆ‫⎇ᧄޔࠄ߆ߣߎߥ߁ࠃߩߎޕ‬ⓥߢ
⺰ߓߚ Ru ㊄ዻߦๆ⌕ߒߚ CO2 ಽሶߩࡌࡦ࠼᭴ㅧߪ‫ޔ‬ㆶర෻ᔕߩ࠻࡝ࠟ࡯ߣߒߡ㊀ⷐߢ޽ࠆߣ⠨߃ࠄࠇࠆ‫৻ޕ‬ᣇ‫ޔ‬Ru ㍲૕ߢߪ CO2 ಽሶߩࡌࡦ࠼ᓟߦ⛯ߊ᳓⚛ൻ෻ᔕߪ CO2 ಽሶౝߩ὇⚛ේሶߦኻߒߡઃടߒ‫↢߇㉄ࠡߦ⊛⚳ᦨޔ‬ᚑߐࠇࠆ‫৻ޕ‬ᣇ‫ޔ‬Ru ⴫㕙਄ߢߩ෻ᔕߢߪ‫ޔ‬CO2 ಽሶౝߩ㉄⚛ේሶߦኻߒߡ᳓⚛߇ઃടߔࠆ‫ޔߚ߹ޕ‬BS ⸅ᇦߢߪ‫ ߷߶ޔ‬100%ߩ෼₸ߢࡔ࠲ࡦಽሶ߇↢ᚑߐࠇߡ߅ࠅ‫↢ߩ㉄ࠡޔ‬ᚑߪ⏕⹺ߐࠇߡ޿ߥ޿‫ޕ‬หߓ Ru ㊄ዻ߇㑐ࠊࠆ෻ᔕߢ޽ࠆߦ߽㑐ࠊࠄߕ‫ޔ‬ဋ৻⸅ᇦߣ࿕૕⸅ᇦߢߩ෻ᔕᕈߪ⇣ߥࠆ‫ޔߥ߁ࠃߩߎޕ‬ဋ৻⸅ᇦߣ࿕૕⸅ᇦߩ෻ᔕᕈߩ㆑޿ࠍ᣿ࠄ߆ߦߔࠆߎߣߪ‫ޔ‬ဋ৻⸅ᇦ߅ࠃ߮࿕૕⸅ᇦ෺ᣇߩൻቇ෻ᔕߩℂ⸃ࠍᷓ߼ࠆߚ߼ߦ߽㊀ⷐߢ޽ࠆ‫ޕ‬4, ⚿⸒ ᧄ⎇ⓥߢߪ‫ޔ‬BS ⸅ᇦߩ෻ᔕࠍ⸃ᨆߔࠆߚ߼ߦ‫৻╙ޔ‬ේℂ㊂ሶൻቇ⸘▚ᚻᴺߦၮߠߊࠦࡦࡇࡘ࡯
࠲࡮ࠪࡒࡘ࡟࡯࡚ࠪࡦࠍⴕߞߚ‫ޕ‬BS ⸅ᇦ਄ߢߩ CO2 ࡔ࠲ࡦൻ෻ᔕߢߪ‫ޔ‬෻ᔕߩ࠻࡝ࠟ࡯ߣߒߡ‫ޔ‬
CO2 ಽሶ߇ Ru ㊄ዻ਄ߢࡌࡦ࠼ߒๆ⌕ߔࠆߎߣ߇㊀ⷐߢ޽ࠆߎߣࠍ␜ߒߚ‫ ߥ߁ࠃߩߎޕ‬CO2 ಽሶߩࡌࡦ࠼ๆ⌕᭴ㅧߪ‫ ࠢ࡞ࡃޔ‬Ru ⴫㕙ߛߌߢߥߊ‫㉄ޔ‬ൻ࠴࠲ࡦ਄ߩ Ru ࠽ࡁ࡮ࠢ࡜ࠬ࠲࡯‫ߡߒߘޔ‬Ru ㍲૕ߢ߽ⷰኤߐࠇࠆ‫ⶄߦ߁ࠃߩߎޕ‬ᢙߩ♽ߢ CO2 ಽሶ߇㊄ዻ਄ߢࡌࡦ࠼ߐࠇ෻ᔕ߇ㅴⴕߔࠆߎ
ߣߪ‫ޔ‬ൻቇ⊛ߦ቟ቯߥ CO2 ಽሶࠍ෻ᔕߐߖࠆߚ߼ߦߪ‫ޔ‬㊄ዻࠍ↪޿ߡ CO2 ಽሶࠍࡌࡦ࠼ߔࠆࠃ߁ߥ㔚ሶ⁁ᘒࠍᒻᚑߔࠆߎߣ߇㊀ⷐߢ޽ࠆߎߣࠍ␜ߒߡ޿ࠆ‫ޕ‬ ╙৻ේℂߦၮߠ޿ߚ⸘▚ൻቇᚻᴺߪ‫ޔ‬࿕૕⸅ᇦߩ෻ᔕ⸃ᨆߢߪᒝജߥ࠷࡯࡞ߣߥࠅᓧࠆ‫৻ޕ‬ᣇ‫ޔ‬࠻࡝࠴࠙ࡓࠍ૶ߞߚห૏૕ߦࠃࠆ෻ᔕ࠻࡟࡯ࠬߪ‫ޔ‬BS ⸅ᇦߩࠃ߁ߥ᳓⚛߇⛊߻♽ࠍ⺞ߴࠆߚ߼ߩ
᦭ജߥᚻᲑߦߥࠆߣᕁࠊࠇࠆ‫▚⸘ޕ‬ൻቇᚻᴺ߿‫ߥ߁ࠃߩ࡯ࠨ࡯࡟࠻࡮ࡓ࠙࠴࡝࠻ޔ‬ታ㛎ᚻᴺ╬ࠍలಽߦᵴ↪ߔࠆߎߣߦࠃࠅ‫ޔ‬BS ⸅ᇦߩ෻ᔕᯏ᭴߇੹ᓟ᣿ࠄ߆ߦߥߞߡ޿ߊߣ⠨߃ࠄࠇࠆ‫ޕ‬⻢ㄉ ᧄ⎇ⓥߩ৻ㇱߪ‫ޔ‬ንጊᄢቇ᳓⚛ห૏૕⑼ቇ⎇ⓥ࠮ࡦ࠲࡯৻⥸౒ห⎇ⓥ A㧔HRC2001-05㧕ߩഥᚑࠍฃߌߡⴕࠊࠇߚ‫ޕ‬

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