Electrochemical and photoelectrochemical experiments were conducted to investigate the pyrite/aqueous interface reaction by using microparticles of synthetic pyrite as electrodes. The potential of the conduction bandedge of pyrite as a function of pH was estimated to be Ec = 0.34 - 0.059 pH in volts vs. saturated calomel electrode (SCE). The open-circuit potential of pyrite electrode in 1 M HNO3 solution was 0.38 VSCE. Illumination of pyrite microelectrodes increased both the anodic current and the dissolution rate dramatically but had little effect on the cathodic current and the cathodic dissolution. These results indicate that pyrite, as an n-type semiconductor, dissolves anodically through a hole transfer (valence band) pathway, while cathodic dissolution only involves electron reaction (conduction band).
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Surfaces, Coatings and Films
- Materials Chemistry