Multiscale measurements of piezoelectric response of hydrothermal converted BaTiO3 1D vertical arrays

Abstract

In this work, the piezoelectric properties of BaTiO3 1D vertical nanostructures were investigated with a comparison between the macroscopic and the nanometric response. The piezoelectric nanostructured carpet was obtained by the topotactic conversion of anodic TiO2 nanotubes exploiting hydrothermal treatment in Ba-enriched water solution. The nanoscale investigation by a piezoelectric force microscope returns a detailed map of ferroelectric polarization, which is preferentially confined over the vertical nanostructure axis. The scanning probe microscopy results were then coupled to the macroscopic response of the piezo-evaluation system to compare the multiscale response of the nanostructured material. Both the local and macroscopic measurement techniques provide d33 values in the range of 5.5–7 pm/V, in agreement with the values reported in the literature for other barium titanate nanostructures. The characterization of the piezoelectric response of BaTiO3 nanostructures at the nanoscale can provide useful guidelines for the next generation of Pb-free materials to be integrated into near-future nanodevices.