US EPA

4967009 

Journal Article 

ON THE FORMATION AND OXIDATION OF A HETEROGENEOUS AMALGAM OF IRON AT ULTRAMICROELECTRODES 

Winkler, K; Mojsa, R 

1995 

1 

Polish Journal of Chemistry
ISSN: 0137-5083 

69 

5 

731-741 

WOS:A1995QY23700012 

Electrode processes involving the formation of heterogeneous amalgam of iron during the electroreduction of Fe(II) ions and the oxidation of the iron amalgam were investigated by voltammetry at hemispherical and thin-layer mercury ultramicroelectrodes. A substantial difference between electrode processes in Fe(II)/Fe(Hg) system at standard size and ultra microelectrodes due to the different mass transfer conditions were found. It was also detected that an intermetallic compound is formed in the Hg - Au - Fe system. As a result, the differences in electrooxidation processes at ultramicroelectrodes with Au base and at Pt, Ag and GC ultramicroelectrodes coated by mercury were observed. The influence of the amount of iron introduced into the mercury ultramicroelectrode on the oxidation process in Fe(II)/Fe(Hg) system was investigated. For high Fe(II) ion reduction charge, a deposition of iron on the electrode surface takes place. The potential of oxidation of iron deposited on the mercury surface is much less anodic than the potential of heterogeneous iron amalgam oxidation. 

MICROELECTRODES; HETEROGENEOUS AMALGAMS; IRON ELECTROCHEMISTRY