ELECTROCHEMISTRY OF FUEL CELL ELECTRODES. ADSORPTION AND OXIDATION OF HCOOH ON SMOOTH PT ELECTRODES IN HC1O4 SOLUTIONS,
Abstract
The adsorption and oxidation of formic acid on smooth pt electrodes was studied in HC1O4 acid solutions by anodic and cathodic chronopotentiometry and by potentiostatic techniques. The oxidation rate at each potential was determined as a function of electrode preparation, pH, and formic acid concentration. Anodic pretreatment activates an electrode for the subsequent oxidation of HCOOH. However, the oxidation rate at any given potential declines with time because of the slow adsorption of a substance which interferes with the oxidation of HCOOH. The kinetics of adsorption and the extent of adsorption of the blocking substance were determined at a series of potentials. The equilibrium adsorption decreases with potential above 0.35v and is essentially zero at 0.70 v. The rate of oxidation of HCOOH is first order with respect to the free surface, the HCOOH concentration, and the pH. A mechanism for oxidation is suggested in which the slow step is a non-electro-chemical, dissociative reaction of HCOOH. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1963
- Accession Number
- AD0424479
Entities
People
- A. C. Makrides
- S. B. Brummer