Preparation of Anhydrous Lanthanum Chloride for LaCl_3:Ce~(3+) Crystal Growth

The preparation of anhydrous lanthanum chloride for LaCl_3:Ce~(3+) crystal growth by chlorinating sintering dehydration process is reported in this paper.The dehydration procedure of(LaCl_3·7H_2O) was investigated by DTA/TG analysis in order to explore an effective way to avoid the hydrolysis reaction.Using(LaCl_3·7H_2O) as the starting materials,anhydrous lanthanum chloride was prepared by the dehydration treatment in HCl atmosphere.The optimum conditions for the chlorinating sintering dehydration process had been obtained by a series of experiments.To confirm the purity of the anhydrous lanthanum chloride obtained,it had been used to grow LaCl_3:Ce~(3+) single crystals.In the chlorinating sintering dehydration process,the anhydrous lanthanum chloride with high purity can be prepared by means of sintering(LaCl_3·7H_2O) at 220230℃ for 6-7h in dried HCl atmosphere.The anhydrous lanthanum chloride is applied to grow colorless transparent LaCl_3:Ce~(3+) single crystals successfully.