Published online by Cambridge University Press: 16 May 2016
The formation of europium sulfides (Eu3S4 and EuS) via CS2 gas sulfurization of Eu2O3 powder was investigated. Single-phase Eu3S4 was obtained via CS2 gas sulfurization of Eu2O3 at 773 K for periods longer than 0.5 hr and EuS was generated by sulfurization at 1073 K for 8 hr. The higher sulfurization temperature and shorter sulfurization time accelerated the formation of high purity EuS. Synthetic pure Eu3S4 was treated under vacuum, rich-sulfur atmosphere and inert atmosphere, respectively. EuS was obtained when heat treatment was performed at 873 K under vacuum, at 973 K under CS2/Ar atmosphere, and at 1073 K under Ar atmosphere. Heat treatment of Eu3S4 generated a small amount of Eu2O2S due to impurity oxygen. Formation of Eu2O2S could be inhibited by heat treatment under CS2/Ar atmosphere.