Infrared Reflection Absorption Spectroscopy of the Sulfuric Acid Anion Adsorbed on Pd(S)−[n(111) × (111)] Electrodes

Adsorption of the sulfuric acid anion (HSO4- or SO42-) has been studied on Pd(S)−[n(111) × (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...