Nanostructured ZnS with random close-packed structure: Synthesis, formation rate, and crystal structure study

Abstract

The chemical precipitation of nanocrystalline ZnS from aqueous alkaline solutions containing zinc ethylenediamine complex salt Zn(En)²⁺ and thiocarbonic acid diamide N₂H₄CS was studied in the course of time in terms of formal chemical kinetics. The ZnS formation rate was found to depend on the concentration of precipitation agent (N₂H₄CS) and to decrease with increasing the ligand (ethylenediamine) concentration, whereas the pH dependence is less pronounced. The size of resulting ZnS nanoparticles does not exceed 5 nm, and their crystal structure was identified as a random close packed structure.