Large-scale fabrication of titanium-rich perovskite PZT submicro/nano wires and their electromechanical properties

We report a 2-step approach to prepare tetragonal perovskite PbZr_0.1Ti_0.9O₃ submicro/nano wires in gram scale and with over 95% wire content. Non-perovskite precursor wires were first fabricated by hydrothermal processing. A subsequent annealing in a PbO atmosphere at 600degC converted these wires into perovskite structures which retain the one-dimensional shape. Binding of the perovksite nanowires to a conductive substrate could be achieved by a similar heat treatment of the non-perovskite precursor wires on a flat Pt coated substrate. Taking advantage of the strong mechanical attachment and good electrical contact between the wires and the metallic layer, piezoresponse force microscopy (PFM) was used to measure the local piezoelectric and ferroelectric properties of the individual wires. Enhanced piezoelectric response relative to sputtered epitaxial PbZr_0.2Ti_0.8O₃ film and squared hysterisis loop with sharp switching indicate pronounced electro- mechanical and ferroelectric behavior. The 90deg domain structure of the as-prepared perovskite PZT wires was confirmed by both PFM and transmission electron microscopy investigations.