Ferroelectric lead zirconate titanate and barium titanate nanoshell tubes
Wetting of the pore walls of porous templates is a simple and convenient method to prepare nanoshell tubes. Wafer-scale fabrication of ferroelectric lead zirconate titanate and barium titanate nanoshell tubes was accomplished by wetting porous silicon templates with polymeric precursors. The ferro- and piezoelectric properties of an individual ferroelectric nanoshell tube either of PZT or of BaTiO3 were electrically characterized by measuring the local piezoelectric hysteresis. A sharp switching at the coercive voltage of about 2 V was shown from the hysteresis loop. The corresponding effective remnant piezoelectric coefficient is about 90 pm/V. We have also prepared highly ordered arrays of free-standing ferroelectric nanoshell tubes obtained by partial etching of the silicon template. Such materials might be used as building blocks of miniaturized devices and could have a significant impact in the field of nano-electromechanical systems.