METHOD FOR PRODUCING RARE EARTH OXYSULFIDE, RARE EARTH OXYSULFIDE, AND REGENERATOR MATERIAL

摘要

Provided are: a method for producing a rare earth oxysulfide, the method including a step (1) for obtaining a mixture A by mixing a sulfate ion source, a solvent, and a rare earth oxide that includes a rare earth element R in a mixture ratio (molar ratio) such that the amount of sulfate ion per mol of rare earth element R is 0.6-0.7 mol, a step (2-A) for obtaining a precipitate by heat-treating the mixture A for two hours or longer at 98°C or higher, and a step (3) for obtaining R₂O₂S by reducing the precipitate in a reducing atmosphere at 600-100°C; and a rare earth oxysulfide obtained by this method. Also provided is a regenerator material including this rare earth oxysulfide.