The electroreduction of Fe(CN)63-, Fe3+, and O2, on the pyrite (FeS2) surface in the dark has been studied with the rotating disk electrode technique. Saturation of the cathodic current density with the concentrations of Fe(CN)63- and Fe3- and with rotation speed was observed. The potential drop within the solid and the Helmholtz layer varied with the applied potential. The results are interpreted in terms of a charge-transfer model involving mediation by bandgap surface states. Fermi level pinning is ascribed to the presence of surface states and the possible origins of these surface states are discussed.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Surfaces, Coatings and Films
- Materials Chemistry