In situ, time-resolved reflectance spectroscopy in the microsecond domain: oxidation of adsorbed carbon monoxide on polycrystalline pt microelectrodes in aqueous solutions.
The dynamics of the electrooxidation of adsorbed CO, COads, on polycrystalline Pt microelectrodes has been examined in CO-saturated 0.5 M H2SO4 and 0.5 M HClO4 aqueous solutions, using in situ, time-resolved, normalized differential reflectance spectroscopy lambda = 633 nm). Attention was focused on the unique dependence of COads oxidation on the potential at which the adsorbed full CO monolayer is assembled (i.e., hydrogen adsorption/desorption vs the double-layer region) using both fast linear scan voltammetry and potential step techniques. As evidenced from the data collected, COads oxidation at a fixed potential proceeds at slower rates when the monolayer is formed in the double- layer region compared to when it is formed in the hydrogen adsorption/desorption region. Possible explanations for this effect are discussed.
Shi
Ping
P
Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106-7078, USA.
Fromondi
Iosif
I
Scherson
Daniel A
DA
D000327:Adsorption; D002248:Carbon Monoxide / Q000737:chemistry*; D003460:Crystallization; D008839:Microelectrodes; D010084:Oxidation-Reduction; D010984:Platinum / Q000737:chemistry*; D012680:Sensitivity and Specificity; D012996:Solutions / Q000737:chemistry; D013053:Spectrophotometry / Q000379:methods*; D013499:Surface Properties; D013997:Time Factors; D014867:Water / Q000737:chemistry
D012996:Solutions; D014867:Water; D010984:Platinum; D002248:Carbon Monoxide