a thermodynamic investigation of the interaction of ferric (fe3+) ion with (100, 110) pyrite and (001) chalcopyrite surfaces using the density functional theory study

As a heterogeneous catalyst, pyrite increases chalcopyrite oxidation by creating more cathodic points and enhancing electron transfer to ferric (fe3+) ions. in this study, the interaction of ferric ions with 100, 110 pyrite surfaces and 001-s, m (m= cu and fe) chalcopyrite surfaces was investigated using the density functional theory (dft) method and material studio software. the results showed that fe3+ ion reacted well with the desired surfaces, and free energies were negative in the 25-275 °c temperature range, and interaction enthalpy increased linearly with increasing temperature. however, the two surfaces of 110 pyrite and 001-s chalcopyrite were more active than other surfaces, and a stronger reaction occurred between the ferric ion and that surfaces. also, due to the strong metal-sulfur bond, the free energy of ferric ion interaction with the 001-m surface of chalcopyrite increased by increasing temperature. however, on the other surfaces, free energy was reduced in the presence of sulfur atoms.