Synthesis of BaZrS₃ in the presence of excess sulfur

Synthetic reaction of barium zirconium sulfide, BaZrS₃, was studied in a large excess amount of sulfur melt at temperatures of 623-723 K and in the presence of a small amount of excess sulfur at temperatures of 623-823 K, respectively. The results showed that BaZrS₃ was formed with high yields by heating at temperatures ranging from 723 to 873 K, if a proper amount of excess sulfur and 10 mole% of BaCl₂ were added in the starting materials. The compound could be obtained in almost a single phase with only 2-3 mole% ZrO₂ impurity after the 8 min water treatment of the products obtained at 873 K. The modified method studied in this paper, i.e. reaction in the medium temperature range of 723-873 K, was shown to be applicable for synthesizing the mixed sulfides of some kinds including BaZrS₃.