Growth and characterization of (Pb, La)(Zr, Sn, Ti)O3 single crystals

Abstract

Relaxor antiferroelectric single crystals, lead lanthanum zirconate stannate titanate (PLZST), with compositions near the morphotropic phase boundary (MPB) were grown by the flux method using PbO–PbF2–B2O3 as a flux. Pale yellow single crystals, which were pseudo-cubes of 1.5–2mm length and 1–2mm thickness, were obtained. Their morphologies and chemical compositions were studied. Compositional deviation was found to occur during crystal growth. The fitted curve of the Ti4+ content in crystals versus that of in raw materials suggested that the chemical composition could draw near to MPB by adding a large amount of Ti4+ in the raw materials. XRD patterns revealed that the calcined powders experienced a gradual phase transition process from tetragonal to rhombohedral with increase in Ti4+ content. Tetragonal phase structures existed in the crystals. The gradual increase in Ti4+ content in the crystals on its increase in raw materials provides valuable information and good foundation for future work.