Flux growth of BiFeO3-PbTiO3 single crystals

Single crystals of BiFeO3-PbTiO3 have been grown from a PbO:Bi2O3 flux by cooling at a rate of 2 °C/h from the melt. Faceted crystals of various morphologies were produced and the size of the crystals ranged from less than 0.5 to 5 mm. The crystals were reflective with smooth facets. Initial measurements were made using scanning electron microscope (SEM) with energy-dispersive X-ray analysis (EDX), quantifying the approximate composition of the crystals. Powder X-ray diffraction (XRD) of the crushed and sieved crystals established that the structure was rhombohedral perovskite for the (BiFeO3)0.75-(PbTiO3)0.25 composition and tetragonal perovskite for the (BiFeO3)0.50-(PbTiO3)0.50 composition. X-ray pole figures verified that the (BiFeO3)0.75-(PbTiO3)0.25 crystal had grown with a single orientation, the [1 0 0] direction. As grown, un-poled (BiFeO3)0.75-(PbTiO3)0.25 crystals exhibited a piezoelectric coefficient (d33) of 18 pC/N in the 〈1 0 0〉 direction.