Interface Controlled Growth of Single-Crystalline PbTiO3 Nanostructured Arrays

Abstract

PbTiO3 (PTO) ferroelectric perovskite has appealing electromechanical characteristics such as low aging rate of the dielectric constant, a high pyroelectric coefficient, a high piezoelectric voltage constant (gij), and a high Curie temperature of 490 °C. However, the high tetragonality of PTO ceramics makes them difficult to be synthesized via conventional high-temperature techniques. Here, a novel synthesis methodology is reported that results in epitaxial growth of a vertically aligned array of PTO nanofibers on a Ti metal substrate. High quality single crystal PTO nanofibers oriented along the [001] PTO direction were obtained on a (110) oriented TiO2 seed layer using a low-temperature hydrothermal synthesis technique. Fundamental understanding of the nucleation and growth criterion is provided through a combination of modeling of the geometric matching of crystal surfaces and experiments detailing the role of underlying TiO2 phase and interplanar atomic configuration. Crystal matching revealed good co...