The growth of LaBrs：Ce^3＋ crystal by the vertical Bridgman process in a nonvacuum atmosphere was reported. According to the dehydration procedure of LaBr3·7H2O and CeBr3·7H2O investigated by differential t...The growth of LaBrs：Ce^3＋ crystal by the vertical Bridgman process in a nonvacuum atmosphere was reported. According to the dehydration procedure of LaBr3·7H2O and CeBr3·7H2O investigated by differential thermal analysis/thermogravimetry （DTA/TG）, anhydrous LaBr3 and CeBr3 were prepared by heating LaBr3·7H2O and CeBr3·7H2O at 240-260℃ for 5-6 h in dried HBr atmosphere. Using the feed materials prepared from the anhydrous lanthanon bromides, a 0.5 mole fraction Ce^3＋ doped LaBr3 crystal with size ofФ25 mm×50 mm had been grown by vertical Bridgman process successfully. By sealing the feed material in a platinum crucible, the crystal could be grown in a nonvacuum atmosphere as the oxidization and volatilization of the melt could be avoided. The crystal was grown with the optimum conditions such as a growth rate of 0.5-1.0 mm/h and a temperature gradient of around 30℃/cm across solid-liquid interface under a furnace temperature of 850-880℃. The crystal was characterized by DTA/TG, X-ray diffraction （XRD）, optical transmission, photoluminescence and X-ray stimulated luminescence measurement. The Bridgman process was confirmed to be promising for growing transparent LaBr3：Ce^3＋ crystal with high optical quality.展开更多
基金supported by the Scientific & Techni-cal Project of Zhejiang Province, China (No 2005C31029)the Doctor Science Foundation of Ningbo City, China(No 2005A610021)
文摘The growth of LaBrs：Ce^3＋ crystal by the vertical Bridgman process in a nonvacuum atmosphere was reported. According to the dehydration procedure of LaBr3·7H2O and CeBr3·7H2O investigated by differential thermal analysis/thermogravimetry （DTA/TG）, anhydrous LaBr3 and CeBr3 were prepared by heating LaBr3·7H2O and CeBr3·7H2O at 240-260℃ for 5-6 h in dried HBr atmosphere. Using the feed materials prepared from the anhydrous lanthanon bromides, a 0.5 mole fraction Ce^3＋ doped LaBr3 crystal with size ofФ25 mm×50 mm had been grown by vertical Bridgman process successfully. By sealing the feed material in a platinum crucible, the crystal could be grown in a nonvacuum atmosphere as the oxidization and volatilization of the melt could be avoided. The crystal was grown with the optimum conditions such as a growth rate of 0.5-1.0 mm/h and a temperature gradient of around 30℃/cm across solid-liquid interface under a furnace temperature of 850-880℃. The crystal was characterized by DTA/TG, X-ray diffraction （XRD）, optical transmission, photoluminescence and X-ray stimulated luminescence measurement. The Bridgman process was confirmed to be promising for growing transparent LaBr3：Ce^3＋ crystal with high optical quality.
