The invention discloses a process method of
rare earth oxysulfide by using an alkali
chloride. The method comprises the following steps: (1) weighing required materials RE2O2S (wherein RE is one of
rare earth elements Y, La, Gd and Sm), Na2CO3, sublimed
sulfur and alkali
chloride AMCl (wherein AM is one of
alkali metal elements Li, Na or K) according to a stoichiometric ratio and uniformly mixing the weighed materials; (2) putting the uniformly
mixed materials into inner and outer crucibles, and filling high-temperature
powder in the gap between the two crucibles and compacting, where each of the two crucibles has a cover; (3) raising the temperature of the crucibles with the mixed material to 1100-1250 DEG C in a gradient way,
sintering for 3-5 hours and then cooling to
room temperature along with a furnace; (4) washing the sintered product with hot water, stirring, and carrying out suction
filtration; and (5)
drying the washed product into a constant-temperature blowing
drying box to obtain the
rare earth oxysulfide. By taking RE2O3, Na2CO3, sublimed
sulfur and alkali
chloride AMCl as raw materials, the rare earth oxysulfide is prepared by using a
sulfur melting method. The preparation method of the rare earth oxysulfide is simple and easy to operate and the rare earth oxysulfide can be used in the fields of light-emitting materials and photoabsorption materials and the like.