Temperature-dependence of Raman spectroscopy on the phase transition in LuBO3

Abstract Temperature-dependence of Raman spectroscopy on LuBO 3 structure was performed in order to obtain information on structural changes induced by temperature evolution. The stability of the calcite phase and low-temperature vaterite phase of LuBO 3 were both evaluated. For the sample with low-temperature vaterite phase, a strong first-order phase transition occurred during 1000–1200 °C, as indicated by the behavior of the Raman modes: the Raman bands split and new bands appear. The transition was associated with the B–O bond being broken in the cyclic B 3 O 9 groups at high temperature, forming an open B 3 O 9 group consisting of BO 4 and BO 3 . Moreover, the influence of In 3+ content on the structural characteristics of LuBO 3 was investigated. It was found that the calcite phase of LuBO 3 can be stabilized up to 1550 °C at least when the n (In)/ n (Lu + In) ratio was more than 20 at%. The crystal growth and characterizations of Lu 1− x In x BO 3 :Ce materials deserve further investigation.