EIS measurements of dithiocarbonate and trithiocarbonate interactions with pyrite and copper

Previous investigations performed on trithiocarbonate (TTC) indicated that the TTC can adsorb onto the surface of a substrate independent of the surface potential. It would appear that the TTC serves as an intermediate for the adsorption of the thiol or thiolate. In this current study it is shown that the TTC indeed adsorbs onto the surface of pyrite and copper independent of the applied potential, where as dithiocarbonate (xanthate) only adsorbs in the presence of an anodic current. However, it is clear that the rate of the TTC adsorption increases in the presence of an anodic current. It is also shown that the thiolate on its own does not show any significant adsorption onto either the pyrite or copper. Thus it confirms that the TTC assists with the adsorption of the thiol or thiolate onto the surface of the substrates.