Hydrothermal Synthesis And Luminescent Properties Of Mono-disperse Fluorides With Peculiar Morphology

In this dissertation, we have successfully synthesized several monodispersed fluorides with peculiar morphology, meanwhile, all kinds of characterizations were used to investigate the reaction condition and main factors which have influences on the morphology, size, and luminescent properties.First, hexagonal-plate LaF3-> CeF3-. PrF3and NdF3-、circle-like SmF3、EUF3and GdF3、walnut-like DyF3and YbF3were prepared in200to240℃. XRD and SEM characterizations indicate that there exists intimate relationship between structure and morphology in rare earth fluorides, among which SmF3is a transition point in the morphology evolution of rare earth fluorides. This is evidently different from the Gardium-broaken effect.Second, Eu3+、Ce3+and Tb3+doped SrF2mondispersed SrF2were successfully prepared. The morphology and size of these SrF2can be tuned by reaction conditions, among which chelating agent、pH and concentration of precursors play. important roles. Eu3+、Tb3+and Ce3+show their characteristic emission, but the strength of their emission is correlated with their morphology.Third, we succeeded in preparing of LiCaAlF6at pH=3and240℃using LiNO3, Ca(NO3)2, A1(NO3)3, and NH4F and discussed the formation process and mechanism of LiCaAlF6in detail.