Growth and characterization of PMNT relaxor-based ferroelectric single crystals by flux method

Relaxor ferroelectric single crystals of lead magnesium niobate-lead titanate (PMNT), in the vicinity of the morphotropic phase boundary, were prepared by the PbO flux method. The microstructure and the growth mechanism of the as-grown single crystals were investigated by scanning electronic microscopy and X-ray diffraction. The growth morphology of PMNT crystals shows the presence of a quasi-cubic {1 0 0} perovskite habit. The growth of the {1 0 0} faces proceeded by means of a layer mechanism and was found to be controlled by 2D nucleation starting at the crystal corners or edges. The perovskite stabilization and phase development were also investigated by thermal analysis. Significant phase transformation from the perovskite to the pyrochlore occurred when PMNT crystals were heated at a relatively high temperature. This suggested that the soaking temperature seriously affects the crystal growth behavior in the PMNT system.