Fundamental Solid Electrode Studies Related to Corrosion Prevention, Fuel Cells and Batteries.

摘要

The study of surface phenomena at solid electrodes related to electrochemical power sources and corrosion processes was the major goal of this research. In particular, three kinds of surface processes were investigated: (1) Underpotential metal deposition, (2) neutral species adsorption and (3) insoluble film formation. New electroanalytical and electrochemical techniques were developed specifically for the purpose of studying such surface processes. These techniques made it possible to prepare solutions with extremely low levels of poisoning substances, to distinguish between surface and mass transport controlled processes, and to perform quantitative studies at the micromolar levels of electroactive species that arose in our studies. Underpotential deposition, UPD, of thallium, mercury and silver on gold have resulted in the determination of accurate adsorption isotherms and highly precise determination of the electrosorption valency. Electrosorption valency values for silver show a minimum near a surface coverage of 0.5. No minimum has ever been discovered before. It is believed that this minimum is caused by either a superlattice phenomena and/or a change in double layer structure. Mercury UPD studies established the existence of a spontaneous coulostatic process that can produce UPD for open circuited metal electrodes. Carbon monoxide, selected as a model neutral species adsorbate, was shown to exist in a number of adsorbed states on platinum.