A Quantum Mechanics Study on the Electronic Structure of Impurity-Bearing Sphalerite (ZnS)

Abstract

A quantum mechanics study on the electronic properties and copper activation of Fe- and Cd-bearing sphalerite (ZnS) has been done using density-functional theory (DFT). Calculated results indicate that Fe impurity introduces the impurity state near the Fermi level and Fe-S bond shows stronger covalent character. Moreover, Fe impurity could not be replaced by Cu atom due to the more stable electronic structure, which results in the reduced copper adsorption amount. For the Cd-bearing ZnS, the Cd-Zn substitution introduces large lattice distortion and the Cd-S bond shows stronger ionic bonding character than Zn-S bond. For Cd-bearing sphalerite, Cd atom is easily replaced by Cu atom, which could increase the Cu2+adsorption. The experiments of copper adsorption on the synthesized Fe-doped and Cd-doped ZnS samples confirm the simulation prediction.