简介 |
PROBLEM TO BE SOLVED : To provide a method for producing a rare earth sulfide sintered compact having a controlled phase even when it has a high impurity oxygen concentration by using a tetragonal rare earth sesquisulfide as a starting material.
SOLUTION : The rare earth sulfide sintered compact is prepared by adding 0.1 to 20 wt.% titanium to a tetragonal rare earth sesquisulfide represented by the compositional formula : Ln2S3 and containing 0.5 to 2.0 wt.% impurity oxygen and sintering the mixture and has a phase transformed from a tetragonal system. In the compositional formula, Ln is at least one member selected from the group consisting of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. Thus, it is possible to easily obtain the rare earth sulfide sintered compact having a controlled crystal structure even when it has a high impurity oxygen concentration and having desirable properties as a thermoelectric conversion material. |