Page 95 - MODERN ASPECTS OF ELECTROCHEMISTRY

Claude LamyAet al.
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Figure 7. SNIFTIR spectra of the adsorbed interme-
diates involved in the oxidation of 0.1 M CH OH in
3
0.5 M HClO on a smooth Pt0.9Ru0.1 bulk alloy (p-po-
4
larized light; modulation potential ∆E = 0.3 V aver-
aging of 128 interferograms). Electrode potential
(mV/RHE); (1) 370, (2) 470, (3) 570, (4) 670, (5) 770.
_
Pt+ (CH 3 OH) sol → Pt (CH 3 OH) ads (17)
•
+
Pt–(CH OH) → Pt–( CH 2 OH) ads +H aq +e – (18)
ads
3
+
or Pt–(CH 3 OH) ads → Pt–(CH O ) +H aq +e – (18′)
3 • ads
_
•
+
Pt (. CH OH) ads → Pt–( CHOH) +H +e – (19)
ads
2
aq
+
or Pt–(CH O ) → Pt–(CH O ) +H +e – (19′)
3 • ads 2 • ads aq
•
•
Pt–( CHOH) → Pt–( CHO) +H +e – (20)
+
aq
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