CO adsorption and kinetics on well-characterized Pd films on Pt(111) in alkaline solutions

The electrochem. of CO on a bare Pt(111) electrode as well as a Pt(111) electrode modified with pseudoamorphic thin palladium films has been studied in alk. soln. by means of Fourier transform IR (FTIR) spectroscopy. First Pd films were prepd. and well characterized in ultra high vacuum and subsequently transferred into the electrochem. cell for the registration of the voltammetric profiles. The charge corresponding to the formation of underpotentially deposited hydrogen (Hupd) on these Pt(1 1 1)-xPd surfaces was established in sulfuric acid soln. as a function of x (0≤x≤1 Pd monolayer (ML)).All subsequent measurements were then performed on electrochem. deposited palladium films using the above Hupd charge vs. Pd coverage relationship to evaluate the amt. of electrochem. deposited palladium. FTIR spectra for CO adsorbed on 1 ML and a submonolayer coverage are compared to those of the unmodified Pt(1 1 1) surface, all surfaces having identical 2D lattice structures. IR absorption bands of CO bound on either Pt(1 1 1) or Pt(1 1 1)-1 ML Pd are clearly distinguished. Spectra of CO adsorbed on Pd submonolayers show characteristic features of both CO bound to Pt and to Pd, indicating that on Pt(1 1 1)-xPd surfaces there is no coupling between Pt-COad and Pd-COad mols. The kinetics of CO oxidn. on these surfaces is detd. either by rotating disk electrode measurements or by FTIR spectroscopy, monitoring the CO32- prodn. The oxidn. of COad on Pt(111) and on Pd modified platinum surfaces starts at the same potential, at ≈0.2 V. The oxidn. rate is, however, considerably lower on the Pt(111)-xPd surfaces than on the Pt(111) surface. The kinetics of CO oxidn. appears to be detd. by the nature of adsorbed hydroxyl anions (OHad), which are more strongly (less active) adsorbed on the highly oxophilic Pd atoms. [on SciFinder(R)]     «

The electrochem. of CO on a bare Pt(111) electrode as well as a Pt(111) electrode modified with pseudoamorphic thin palladium films has been studied in alk. soln. by means of Fourier transform IR (FTIR) spectroscopy. First Pd films were prepd. and well characterized in ultra high vacuum and subsequently transferred into the electrochem. cell for the registration of the voltammetric profiles. The charge corresponding to the formation of underpotentially deposited hydrogen (Hupd) on these Pt(1 1 1...     »

Adsorption Adsorption Chemically modified electrodes (CO adsorption and kinetics on well-characterized Pd films on Pt(111) in alk. solns.) Oxidation kinetics (of CO adsorbed on well-characterized Pd films on Pt(111) in alk. solns.) IR spectra (of Co adsorbed on Pt(111) and Pd films on Pt(111) in KOH solns.) Cyclic voltammetry (of Pt(111) electrode with various amts. of Pd deposited, in H2SO4 and KOH solns.) Oxidation (of carbon monoxide on Pd films on Pt(111) in alk. solns.) carbon monoxide adsorption kinetics palladium film platinum IR spectroscopy     «

Adsorption Adsorption Chemically modified electrodes (CO adsorption and kinetics on well-characterized Pd films on Pt(111) in alk. solns.) Oxidation kinetics (of CO adsorbed on well-characterized Pd films on Pt(111) in alk. solns.) IR spectra (of Co adsorbed on Pt(111) and Pd films on Pt(111) in KOH solns.) Cyclic voltammetry (of Pt(111) electrode with various amts. of Pd deposited, in H2SO4 and KOH solns.) Oxidation (of carbon monoxide on Pd films on Pt(111) in alk. solns.) carbon monoxide adso...     »

CAN 137:191915 72-2 Electrochemistry Institut fur Physikalische und Theoretische Chemie, Universitat Bonn, Bonn, Germany. Journal 0039-6028 7440-05-3P (Palladium) Role: CPS (Chemical process), PEP (Physical, engineering or chemical process), PNU (Preparation, unclassified), PRP (Properties), PREP (Preparation), PROC (Process) (CO adsorption and kinetics on well-characterized Pd films on Pt(111) in alk. solns.); 630-08-0 (Carbon monoxide) Role: PEP (Physical, engineering or chemical process), PRP (Properties), PYP (Physical process), PROC (Process) (adsorption and kinetics on well-characterized Pd films on Pt(111) in alk. solns.); 1310-58-3 (Potassium hydroxide); 7664-93-9 (Sulfuric acid) Role: NUU (Other use, unclassified), USES (Uses) (cyclic voltammetry of Pt(111) electrode with various amts. of Pd deposited, in H2SO4 and KOH solns.); 7440-06-4 (Platinum) Role: DEV (Device component use), USES (Uses) (single crystal; CO adsorption and kinetics on well-characterized Pd films on Pt(111) in alk. solns.)     «

CAN 137:191915 72-2 Electrochemistry Institut fur Physikalische und Theoretische Chemie, Universitat Bonn, Bonn, Germany. Journal 0039-6028 7440-05-3P (Palladium) Role: CPS (Chemical process), PEP (Physical, engineering or chemical process), PNU (Preparation, unclassified), PRP (Properties), PREP (Preparation), PROC (Process) (CO adsorption and kinetics on well-characterized Pd films on Pt(111) in alk. solns.); 630-08-0 (Carbon monoxide) Role: PEP (Physical, engineering or chemical process), PR...     »