Vibrational properties of CO at the Pt(111)-solution interface: the anomalous Stark-tuning slope.
Vibrational properties of CO have been studied on Pt(111) in acid and alkaline electrolytes by synchronous measurements of CO oxidation current (0.5 mV/s) and IRAS spectra (one spectrum for every 1 mV). We found that in acid solutions the frequency-tuning rate (dnu(CO)/dE) as well as the potential-dependent bandwidth (dDeltanu1/2/dE) deviates from expected linear relationships. This unusual potential-dependent behavior is interpreted in terms of compression/dissipation of CO islands during the CO oxidation, engendered by competitive adsorption between inactive anions from a supporting electrolyte and the reactive OH species.
Stamenkovic
V
V
Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
Chou
K C
KC
Somorjai
G A
GA
Ross
P N
PN
Markovic
N M
NM
D002248:Carbon Monoxide / Q000737:chemistry*; D004566:Electrodes; D004573:Electrolytes / Q000737:chemistry; D006878:Hydroxides / Q000737:chemistry*; D010084:Oxidation-Reduction; D010472:Perchlorates / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry*; D017680:Potassium Compounds / Q000737:chemistry*; D012996:Solutions / Q000737:chemistry; D013464:Sulfuric Acids / Q000737:chemistry*; D013499:Surface Properties; D014732:Vibration
D004573:Electrolytes; D006878:Hydroxides; D010472:Perchlorates; D017680:Potassium Compounds; D012996:Solutions; D013464:Sulfuric Acids; D010984:Platinum; D002248:Carbon Monoxide; C033158:sulfuric acid; C029943:potassium hydroxide