METHOD OF OBTAINING POLYCRYSTALS OF FOUR COMPOUNDS ALnAgS (A = Sr, EU; Ln = Dy, Ho) Russian patent published in 2019 - IPC C01B17/20 C01B17/43 C30B28/00 C30B29/46 C01F17/00 H01F1/40 C09K11/77 C09K11/84 G02B1/02 

FIELD: chemistry.

SUBSTANCE: invention relates to the field of inorganic chemistry, in particular, to a method for producing polycrystals of quaternary compounds ALnAgS₃ (A=Sr, Eu; Ln=Dy, Ho) monoclinic system with a BaErAgS₃ type structure, that are promising for use as phosphors, semiconductors and non-metallic ferromagnets, optical materials. Initial precursor is prepared from stoichiometric amounts Ag, SrCO₃ (Eu₂O₃), Ln₂O₃, that dissolve in nitric acid, precipitated 5–10 wt. % excess of sulfuric acid, the solution with the cocrystallized sulphate precipitate is evaporated at 80–110 °C, annealed at 500 °C for 7 h, triturated to a dispersion corresponding to a particle size of less than 60 microns, and conduct stepwise high-temperature processing of cocrystallized sulphate charge in stream H₂S and CS₂ in the ratio of 1:2 (argon gas carrier) at 600 °C for 2–3 hours, at 900 °C for 50 hours or at 700 °C for 90 hours.

EFFECT: invention allows to obtain chemically homogeneous compounds with a content of the target phase of at least 99 mol% ALnAgS₃.

1 cl, 2 ex