Infrared reflection absorption spectroscopy of the sulfuric acid anion adsorbed on Pd(S)-[n(111) x (111)] electrodes.
Adsorption of the sulfuric acid anion (HSO4- or SO42-) has been studied on Pd(S)-[n(111) x (111)] electrodes (n = 2, 3, 5, 9, 20, infinity) using in situ infrared reflection absorption spectroscopy (IRAS). A single band is observed around 1200 cm(-1) on all the electrodes. The band is assigned to the SO stretching vibration of the sulfuric acid anion adsorbed with three- or onefold geometry. This result differs from the case of Pt-stepped surfaces on which two IRAS bands are observed around 1200 and 1100 cm(-1). The maximum coverage of the sulfuric acid anion is enhanced with the increase of the terrace width. The surfaces with n more than 3 have similar IRAS band shifts (dv/dE). Pd-stepped surfaces, for which the terrace is wide enough for the anion adsorption, adsorb the anion on the terrace rather than the step.
Department of Applied Chemistry, Faculty of Engineering, Chiba University, 1-33, Yayoi-cho, Inage-ku, Chiba 263-8522, Japan. hoshi@faculty.chiba-u.jp
Nagahiro
N
Hoshi
Makiko
M
Kuroda
Takehiko
T
Ogawa
Osamu
O
Koga
Yoshio
Y
Hori