Hierarchical PbTiO₃ Nanostructures Grown on SrTiO₃ Substrates

Abstract

A synthesis route, based on a hydrothermal treatment of an amorphous PbTiO3 precursor at 180 °C, has been developed to grow hierarchical PbTiO3 nanostructures on single-crystal SrTiO3 substrates. Initially, highly oriented PbTiO3 platelets grew parallel to the ⟨100⟩ substrate orientations. PbTiO3 nanorods with squared cross-section were shown to grow perpendicular out of the platelets. The length of the rods could be controlled by the vertical position of the substrate in the autoclave. Furthermore, changing the crystallographic orientation of the substrate resulted in a systematic change in the orientation of the nanorods. Finally, growth of PbTiO3 nanorods perpendicular to the substrate surface was demonstrated by hindering the initial growth of PbTiO3 platelets.