ELECTROCHEMISTRY OF FUEL CELL ELECTRODES. HYDROGEN OVERVOLTAGE AT A DROPPING THALLIUM AMALGAM ELECTRODE.
Abstract
Measurements were made of hydrogen overvoltage, in 0.1 M HClO4, at temperatures from 14 to 69 C, at dropping amalgam electrodes containing 10.0 and 40.6 mole percent thallium. The overvoltage was 20 to 30 millivolts higher on 40% Tl amalgam than on mercury. When corrections were made for the effect of the diffuse double layer, the exchange current for hydrogen discharge at 25 C was found to decrease by a factor of 2 on going from Hg to 40% Tl amalgam. The temperature dependence of overvoltage gives an enthalpy of activation (extrapolated to the reversible hydrogen potential) of 22.3 = 0.4, 21.2 = 1.1, and 23.1 = 0.3 kcal/mole for Hg, 10% Tl amalgam, and 40% Tl amalgam respectively. Thus, both the overvoltage and the enthalpy of activation are higher on Tl amalgams than on Hg. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1965
- Accession Number
- AD0461758
Entities
People
- Evelyn A. Barron-apps
- James N. Butler
- Mary L. Meehan