Influence of underpotential deposited lead upon the oxidation of HCOOH in HClO[sub 4] at platinum electrodes

Journal Article · Wed Sep 01 04:00:00 EDT 1993 · Journal of the Electrochemical Society; (United States)

DOI:https://doi.org/10.1149/1.2220862· OSTI ID:5676788

Xia, X H; Iwasita, T ^[1]

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1. Inst. fuer Physikalische Chemie der Universitat Bonn (Germany)

The oxidation of formic acid on noble metals such as platinum or palladium has been studied extensively in the last decades due to its significance in electrocatalysis of fuel-cell reactions. The influence of stabilized, underpotential deposited (upd) lead on the oxidation of formic acid and its strongly absorbed species on a platinum electrode in HClO[sub 4] has been investigated by measuring simultaneously the rate of CO[sub 2] production from both bulk and adsorbed formic acid. The use of on-line mass spectrometry (MS) technique (DEMS) allows a discrimination of the products (CO[sub 2]) between adsorbed and bulk species with the help of isotope-labeled [sup 13]C formic acid as a probe. The pronounced catalytic effect of upd lead adatoms on the bulk formic acid oxidation strongly depends on the coverage degree of adatoms. In addition, upd Pb facilitates the oxidation of formic acid adsorbates. However, the oxidation of formic acid cannot take place on a Pt surface covered up to 100% with upd lead adatoms and CO adsorbates. The results prove once more that a third-body effect cannot account for the observed catalytic effects. An electronic interaction between the upd Pb and the Pt substrate is more likely. This result in an increase in rate of HCOOH electrosorption on the modified free-platinum surface.

• OSTI ID: 5676788
• Journal Information: Journal of the Electrochemical Society; (United States), Journal Name: Journal of the Electrochemical Society; (United States) Vol. 140:9; ISSN JESOAN; ISSN 0013-4651
• Country of Publication: United States
• Language: English

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30 DIRECT ENERGY CONVERSION
300503* -- Fuel Cells-- Materials
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300505 -- Fuel Cells-- Electrochemistry
Mass Transfer & Thermodynamics
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CARBOXYLIC ACIDS
CATALYTIC EFFECTS
CHALCOGENIDES
CHEMICAL REACTIONS
CHEMISTRY
CHLORINE COMPOUNDS
DATA
DEPOSITION
DIRECT ENERGY CONVERTERS
ELECTROCHEMICAL CELLS
ELECTROCHEMISTRY
ELECTRODEPOSITION
ELECTROLYSIS
ELEMENTS
EXPERIMENTAL DATA
FORMIC ACID
FORMIC ACID FUEL CELLS
FUEL CELLS
HALOGEN COMPOUNDS
HYDROGEN COMPOUNDS
INFORMATION
INORGANIC ACIDS
LEAD
LYSIS
METALS
MONOCARBOXYLIC ACIDS
NUMERICAL DATA
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXIDATION
OXIDES
OXYGEN COMPOUNDS
PERCHLORIC ACID
PLATINUM
PLATINUM METALS
SURFACE COATING
TRANSITION ELEMENTS