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 degrees 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 5mm. 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 [10 0] direction. As grown, un-poled (BiFeO3)(0.75)-(PbTiO3)(0.25) crystals exhibited a piezoelectric coefficient (d(33)) of 18 pC/N in the < 10 0 > direction. (c) 2005 Elsevier B.V. All rights reserved.