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Лекции - часть 3
.pdf![](/html/2706/378/html_wvls8fh2ec.o1wS/htmlconvd-b9zh4_111x1.jpg)
O2 из газовой фазы
OHads
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1 |
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0.8 |
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OH |
0.6 |
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0.4 |
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0.2 |
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0 |
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0 |
0.2 |
0.4 |
0.6 |
0.8 |
1 |
1.2 |
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Potential vs SHE, V |
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Wang, 2004
WORR k e |
F |
O2 1 OH 2 , |
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Основные стадии: |
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RT |
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KOH E, OH e |
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F |
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1 OH |
1. |
O2 + 2S S2O2ads |
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– быстро |
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RT |
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H |
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OH |
2. |
S2O2ads + H+ + e- S2O2Hads |
– медленно, rds |
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При низком перенапряжении |
3. |
H O + S OH |
ads |
+ H+ |
+ e- |
- быстро |
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OH 1 |
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2 |
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111
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Pt3Co
С поверхности вымывается Co, остается только Pt
Stamenkovic, 2007
Адсорбция OH
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0.4 |
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OH |
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Pt |
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0.2 |
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Pt3Ni |
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0 |
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0.4 |
0.5 |
0.6 |
0.7 |
0.8 |
0.9 |
1 |
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Potential vs RHE, V |
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High Eact |
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High |
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V |
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Fe |
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Pt3Co |
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at0.33Pt |
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Pt3V |
Pt3Ni |
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Current |
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1 |
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Pt (poly) |
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0 |
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-3.6 |
-3.4 |
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-3.2 |
-3 |
-2.8 |
-2.6 |
-2.4 |
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d-band center shift, eV |
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112 |
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Перенапряжение на катоде для чистой Pt и биметаллических катализаторов |
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0.5 |
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Pt (poly) |
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70 mV |
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V |
0.4 |
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Overvoltage, |
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Pt3Ni |
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Pt3Co |
0.3 |
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0.2 |
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0.1 |
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0 |
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0 |
5 |
10 |
15 |
20 |
25 |
30 |
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Current, mA/cm2 |
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113 |